tag:theconversation.com,2011:/ca/topics/coastal-erosion-8716/articlesCoastal erosion – The Conversation2024-03-28T00:33:06Ztag:theconversation.com,2011:article/2256642024-03-28T00:33:06Z2024-03-28T00:33:06ZCoastal dunes are retreating as sea levels rise - our research reveals the accelerating rate of change<figure><img src="https://images.theconversation.com/files/584278/original/file-20240326-28-gjzijw.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C4000%2C2250&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Patrick Hesp</span></span></figcaption></figure><p>In some parts of Australia, coastal dunes are retreating from the ocean at an alarming rate, as waves carve up the beach and wind blows the sand inland. But coastal communities are largely oblivious to the changes.</p>
<p>Our <a href="https://www.sciencedirect.com/science/article/abs/pii/S0169555X24001156">new research</a> documents the retreat, revealing an accelerating rate of change along Australia’s longest coastal dunefield, in South Australia. These beaches are being reshaped in the geological blink of an eye. </p>
<p>Wave action is eroding the shoreline and the wind is carrying the sand further inland, where new dunes are being formed. Climate change may be <a href="https://theconversation.com/climate-fuelled-wave-patterns-pose-an-erosion-risk-for-developing-countries-184064">accelerating the rate of change</a> by increasing <a href="https://www.science.org/doi/full/10.1126/science.aav9527">ocean wind speeds and wave heights</a>.</p>
<p>This provides yet another reason to reduce emissions and limit global warming – before our beaches and dunes disappear before our very eyes. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/UEykBpCvLEE?wmode=transparent&start=10" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Drone footage from Younghusband Peninsula in South Australia (Patrick Hesp)</span></figcaption>
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Read more:
<a href="https://theconversation.com/how-rising-sea-levels-will-affect-our-coastal-cities-and-towns-221121">How rising sea levels will affect our coastal cities and towns</a>
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<h2>Australia’s longest stretch of coastal dunes</h2>
<p>Our South Australian study site, the Younghusband Peninsula, is the longest coastal dune system in Australia. It extends some 190km from the Murray River mouth at Goolwa to Kingston in the state’s southeast. </p>
<figure class="align-left ">
<img alt="Locator maps pinpointing the dune study area, half a mile southeast of 42 Mile Crossing in South Australia" src="https://images.theconversation.com/files/584283/original/file-20240326-30-gbypzc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/584283/original/file-20240326-30-gbypzc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1296&fit=crop&dpr=1 600w, https://images.theconversation.com/files/584283/original/file-20240326-30-gbypzc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1296&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/584283/original/file-20240326-30-gbypzc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1296&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/584283/original/file-20240326-30-gbypzc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1629&fit=crop&dpr=1 754w, https://images.theconversation.com/files/584283/original/file-20240326-30-gbypzc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1629&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/584283/original/file-20240326-30-gbypzc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1629&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The dune study area in South Australia was half a mile southeast of 42 Mile Crossing.</span>
<span class="attribution"><span class="source">Patrick Hesp</span></span>
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<p>The shoreline of the central region of the peninsula, near 42 Mile Crossing in the Coorong National Park, started eroding in the early 1980s.</p>
<p>Our new research has found the shoreline has eroded about 100 metres since that time, at an average rate of 1.9m per year. Recently this has become much faster and is now up to 3.3 metres a year. That’s equivalent to losing a tennis court from the front of your house every seven years.</p>
<p>Meanwhile, the dunes are marching inland at an incredible rate of 10 metres a year. </p>
<p>This is an extraordinary rate of change. If the shoreline erosion trend continues, it will dramatically change the national park dune system. </p>
<p>Dune sands may also invade the iconic Coorong Lagoon, impacting the Ramsar-listed wetland of international significance. Sand could slowly fill the lagoon, transforming the environment and reducing the habitat available for fish, waterbirds and other wildlife.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Aerial imagery showing the formation of new sand dunes as the shoreline is eroded by waves" src="https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=275&fit=crop&dpr=1 600w, https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=275&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=275&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=346&fit=crop&dpr=1 754w, https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=346&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/584299/original/file-20240326-18-ldeufl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=346&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Contrasting aerial imagery from 1978, 1995, 2005, 2008, 2013 and 2019, showing erosion of the shoreline and formation of new sand dunes.</span>
<span class="attribution"><span class="source">Marcio DaSilva using images from Google Earth</span></span>
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<p>Our research also examined how the shoreline has changed over the past 80 years, using <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/esp.5400">aerial photography and satellite imagery</a>, and when the dunes on the Younghusband Peninsula formed, using various dating methods, historical aerial photography from 1945, and satellite imagery. We found they are forming at a very rapid rate. </p>
<p>This new field of coastal dunes developed in just over a decade. The landward edge of the dunefield has moved inland more than 100 metres in eight years.</p>
<p>Three factors may be causing the shoreline erosion and subsequent dune evolution. Offshore reefs that would have protected the coastline have been breaking down. Sea level has been slowly rising since 1920, so higher waves may be reaching the shore. And wave energy has been increasing in the Southern Ocean in the past ten years. </p>
<p><iframe id="tc-infographic-1030" class="tc-infographic" height="400px" src="https://cdn.theconversation.com/infographics/1030/4cf3eba59b2b09275ba18abf4e6a63f0c94b2b04/site/index.html" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>Shaping coastal dunes</h2>
<p>Large dune systems are formed by sediment transported by waves from the ocean and the surfzone (where waves break). Once waves deposit the sand on the beach, the wind transports it landwards, creating dunes. </p>
<p>Where large amounts of sediment are delivered to a beach and blown inland, “transgressive” dunes may form. We also examined what drives the development of a transgressive dunefield.</p>
<p>Our research shows there are various factors involved, including:</p>
<ul>
<li>high sediment supply from the nearshore and beach system</li>
<li>rising sea level acting as a marine bulldozer that pushes sediments shorewards</li>
<li>wave scarping (creating steep, precipitous sand cliffs that are then prone to collapse) followed by wind erosion of dunes at the back of the beach</li>
<li>climate change resulting in lower rainfall, stronger winds, and a lowering of the water table, which all affect plant growth.</li>
</ul>
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<p>
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<strong>
Read more:
<a href="https://theconversation.com/climate-fuelled-wave-patterns-pose-an-erosion-risk-for-developing-countries-184064">Climate-fuelled wave patterns pose an erosion risk for developing countries</a>
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<h2>The eroded area is expanding north and south</h2>
<p>Our continuing observations and fieldwork show beach erosion and scarping now <a href="https://cmi.ga.gov.au/data-products/dea/581/dea-coastlines">extends for several kilometres</a> northwest and southeast of the area near 42 Mile Crossing.</p>
<p>Underlying older dunes are being cannibalised by the wind. As the scarp slope retreats, it supplies sediment that continues <a href="https://www.sciencedirect.com/science/article/abs/pii/S0169555X24001156">building up the dunes</a> and transporting sand landwards across the older dunefield.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An oblique aerial view of the study site showing the formation of steep sand cliffs (~12m high) and new sand dunes smothering vegetation inland" src="https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/584245/original/file-20240325-30-ap7je9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Drone footage shows wave action is forming steep sand cliffs (~12m high). The new sand dunes are cannibalising and migrating over the older vegetated dunes.</span>
<span class="attribution"><span class="source">Patrick Hesp</span></span>
</figcaption>
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<p>Drone footage shows how wave erosion of the shoreline combined with wind-driven erosion can trigger the creation of a transgressive dunefield. </p>
<p>Our research shows many of the standard assumptions about the development rates and timescales of dunefield evolution may be wrong. If erosion at this site continues to extend north and south, massive changes to the dunefield system, coastal habitats and possibly the Coorong Lagoon may occur. </p>
<p>Such shoreline erosion and dunefield changes suggest what may happen in future to many Australian beach and dune systems as sea levels continue to rise with climate change.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/K7yAXN-9Jjo?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Flinders University Professor Patrick Hesp talks about his research into coastal dunes.</span></figcaption>
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<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/become-a-beach-scientist-this-summer-and-help-monitor-changing-coastlines-214307">Become a beach scientist this summer and help monitor changing coastlines</a>
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<img src="https://counter.theconversation.com/content/225664/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Patrick Hesp receives funding from Australian Research Council</span></em></p><p class="fine-print"><em><span>Marcio D. DaSilva does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Some Aussie beaches are being reshaped and coastal dunes are marching inland. We used data from aerial photography, field surveys, laser mapping and drones to study incredible rates of change.Patrick Hesp, Professor, Flinders UniversityMarcio D. DaSilva, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2244102024-03-15T13:32:03Z2024-03-15T13:32:03ZRavenser Odd: the medieval city Yorkshire lost to the sea<p>April 1 2024 marks the 725th anniversary of King Edward I granting royal charters to two settlements in the north of England: <a href="https://beta.nationalarchives.gov.uk/explore-the-collection/stories/ravenser-odd/">Kingston upon Hull and Ravenser Odd</a>. </p>
<p>The first, of course, is better known as Hull, the city on the banks of the Humber estuary that today <a href="https://www.humber.com/Estuary_Information/">handles a quarter</a> of UK seaborne trade. </p>
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<img alt="A medieval painted portrait." src="https://images.theconversation.com/files/581030/original/file-20240311-24-8pi1bo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/581030/original/file-20240311-24-8pi1bo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=621&fit=crop&dpr=1 600w, https://images.theconversation.com/files/581030/original/file-20240311-24-8pi1bo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=621&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/581030/original/file-20240311-24-8pi1bo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=621&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/581030/original/file-20240311-24-8pi1bo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=780&fit=crop&dpr=1 754w, https://images.theconversation.com/files/581030/original/file-20240311-24-8pi1bo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=780&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/581030/original/file-20240311-24-8pi1bo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=780&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Edward I.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Edward_I_of_England#/media/File:Edward_1.png">Wikimedia</a></span>
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<p>Few will have heard of the second, though. Despite its relative importance in 1299, today, Ravenser Odd has been largely forgotten – because it disappeared, swallowed by the North Sea. It is, as one journalist put it, <a href="https://www.readersdigest.co.uk/inspire/life/yorkshires-atlantis-rediscovering-a-lost-medieval-city">“Yorkshire’s Atlantis”</a>.</p>
<p>Since 2021, I have taken responsibility for the seafloor searches for Ravenser, using high-resolution seafloor mapping equipment and interpreting the resulting data with local historian Phil Mathison. The story of Ravenser Odd and the search for its remains are the focus of an <a href="https://maritimehull.co.uk/whats-happening/news/news-new-exhibition-tells-the-untold-story-of-ravenser-odd">exhibition</a> at the Hull History Centre.</p>
<h2>The northern city that sank</h2>
<p>Ravenser Odd began life as a port on the narrow spit of shingle and clay known as <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/esp.4991">Spurn Head</a> that forms the north bank of the mouth of the Humber. The town grew into a prosperous settlement. </p>
<figure class="align-center ">
<img alt="An old map of the Humber river." src="https://images.theconversation.com/files/581025/original/file-20240311-22-zmunxn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/581025/original/file-20240311-22-zmunxn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=372&fit=crop&dpr=1 600w, https://images.theconversation.com/files/581025/original/file-20240311-22-zmunxn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=372&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/581025/original/file-20240311-22-zmunxn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=372&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/581025/original/file-20240311-22-zmunxn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=468&fit=crop&dpr=1 754w, https://images.theconversation.com/files/581025/original/file-20240311-22-zmunxn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=468&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/581025/original/file-20240311-22-zmunxn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=468&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The Lost Towns of the Humber.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/w/index.php?curid=66063833">British Library|Wikimedia</a></span>
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<p>The 1299 charter made Ravenser into a recognised borough and exempted its merchants from some taxes. This allowed the town to <a href="https://www.historyanswers.co.uk/medieval-renaissance/how-cromwells-christmas-ban-was-enforced-or-not/">build</a> its own court, jail and chapel. It was represented by two members of parliament. </p>
<p>The town <a href="https://beta.nationalarchives.gov.uk/explore-the-collection/stories/ravenser-odd/#h2.becoming-a-borough">contributed ships</a> to Edward I and Edward II’s <a href="https://theconversation.com/the-battle-all-scots-know-about-that-changed-english-history-28520">wars with Scotland</a>. Life in the town was lawless. Its envious rivals on the Humber, Grimsby and Hull, accused Ravenser of <a href="https://beta.nationalarchives.gov.uk/explore-the-collection/stories/ravenser-odd/">piracy</a>, as did German merchants and the king of Norway. </p>
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<img alt="A medieval painted portrait." src="https://images.theconversation.com/files/581069/original/file-20240311-18-ost4b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/581069/original/file-20240311-18-ost4b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=592&fit=crop&dpr=1 600w, https://images.theconversation.com/files/581069/original/file-20240311-18-ost4b7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=592&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/581069/original/file-20240311-18-ost4b7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=592&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/581069/original/file-20240311-18-ost4b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=744&fit=crop&dpr=1 754w, https://images.theconversation.com/files/581069/original/file-20240311-18-ost4b7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=744&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/581069/original/file-20240311-18-ost4b7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=744&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Edward II.</span>
<span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/d/d1/Edward_II_-_British_Library_Royal_20_A_ii_f10_%28detail%29.jpg">British Library|Wikimedia</a></span>
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<p>By the mid-14th century, the storms and strong tidal currents of the North Sea began to take their toll on the settlement. A devastating blow was dealt in 1362 by the storm surge of <a href="https://doi.org/10.1515/9783110719628">St Marcellus’s flood</a> after which the town began to be abandoned. </p>
<p>The very forces that created the land that Ravenser was situated on – and gave it an advantage over other ports on the Humber – were to end its pre-eminence as a trading hub. As recorded in the <a href="https://www.dhi.ac.uk/cistercians/cistercian_life/women/guests/guests3.php">Meaux Abbey Chronicle</a>, by the end of the 14th century, corpses in the graveyard were being exposed by the sea. There were reports of <a href="https://www.historyanswers.co.uk/medieval-renaissance/ravenser-odd-a-medieval-pirate-town-that-was-swallowed-by-the-sea/">looting</a> of the chapel by “sacrilegious persons”.</p>
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<h2>Coastal erosion</h2>
<p>The Holderness coastline, to the north of the Spurn peninsula, is the <a href="https://www.lyellcollection.org/doi/abs/10.1144/1470-9236/08-032">fastest eroding coastline in Europe</a>. Its crumbling cliffs of soft boulder clay are retreating at an average rate of two metres a year. </p>
<p><a href="https://archive.org/details/losttownsofyorks00sheprich/page/44/mode/2up">Thirty settlements</a> are known to have been lost. The location of Ravenser Odd, though, has long remained contested because the historical evolution of Spurn Head remains uncertain. There have been no reports of structures from Ravenser for over 500 years. Suggested locations are thus linked to the various theories on the evolution of Spurn Head. </p>
<p>One theory, <a href="https://www.jstor.org/stable/621074">put forward in the 1960s</a>, describes a 250-year cyclical evolution of Spurn in which the peninsula gradually extends further across the mouth of the Humber until it is breached. The resulting island gradually erodes while a new spit is formed further inland. This would place Ravenser around <a href="https://www.jstor.org/stable/621074">2km offshore</a> from the present peninsula. </p>
<p>Other theories suggest that the neck of the peninsula retreats constantly in line with the erosion of Holderness. This places Ravenser not far <a href="https://publications.naturalengland.org.uk/file/5352378765410304">from the current shoreline</a>. </p>
<p>Still, other theories site Ravenser on an area of shingle on the Humber side of Spurn Head that is uncovered at low tide. Some remains of buildings were discovered here in the 19th century, although they may date from later historical periods than the records we have of Ravenser.</p>
<p>Spurn’s remoteness and the inhospitable conditions of the North Sea give the peninsula a feeling of otherworldliness. The sense of isolation was enhanced in <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/esp.4991">2013</a> when the road along the 3km-long peninsula was cut off by a storm surge. </p>
<p>Conditions in the estuary make it difficult to search for traces of the lost town. In late 2021, <a href="https://www.abebooks.com/9780956299437/Legendary-Lost-Town-Ravenser-Mathison-0956299431/plp">Phil Mathison</a> set up a collaboration with Hull University to <a href="https://www.bbc.co.uk/news/uk-england-humber-59232132">survey the seafloor</a>. </p>
<p>The high-resolution survey instrument we used, a multibeam echosounder, is routinely used by <a href="https://link.springer.com/chapter/10.1007/978-3-319-57852-1_3">earth scientists</a>, harbour authorities and <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1095-9270.2010.00271.x">archaeologists</a> to map the seafloor. Our <a href="https://www.bbc.co.uk/news/uk-england-humber-60401896">survey</a> focused on an area where a seafloor anomaly had been previously seen by Mathison. </p>
<p>However, we failed to identify anything that could be identified as structural remains. This could be due to the constantly shifting sediment of the seafloor.</p>
<p>We will continue the hunt for Ravenser using instruments called parametric echosounders. These are capable of probing below the layers of seafloor sediment and would be deployed at locations identified as areas of interest from the previous surveys. </p>
<p>Land surveys of the subsurface would be possible using a combination of ground-penetrating radar and magnetic gradiometry during low tide. The latter was recently used <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0265463">to discover</a> the remains of the village of Rungholt off the coast of Germany, also lost to St Marcellus’s storm of 1362.</p>
<p>In a region where life on the coastline remains precarious, the focus of the 725th anniversary of Ravenser’s charter has renewed interest in the town and its historical and symbolic importance. As our climate continues to warm, difficult <a href="https://www.lyellcollection.org/doi/abs/10.1144/pygs.59.1.288">coastal management decisions</a> will be exacerbated by the increased likelihood of storms. This makes the story of the city Yorkshire lost poignantly relevant. </p>
<p><em>Hull/Ravenser Odd: twin cities, sunken pasts is on until May 30 2024 at the Hull History Centre.</em></p><img src="https://counter.theconversation.com/content/224410/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steve Simmons does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Dubbed Yorkshire’s Atlantis, Ravenser Odd has been largely forgotten, despite its importance in the 13th century. That’s because it was swallowed by the sea.Steve Simmons, Lecturer in Energy and Environment, University of HullLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2223932024-02-06T05:02:52Z2024-02-06T05:02:52ZClimate change will strike Australia’s precious World Heritage sites – and Indigenous knowledge is a key defence<figure><img src="https://images.theconversation.com/files/573359/original/file-20240205-25-njg9qp.jpg?ixlib=rb-1.1.0&rect=64%2C6%2C4217%2C2837&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Cezary Wojtkowski, Shutterstock</span></span></figcaption></figure><p>From Kakadu to Uluru and the Great Barrier Reef, to Sydney Opera House and the convict sites, <a href="https://www.dcceew.gov.au/parks-heritage/heritage/places/world-heritage-list">Australia’s list</a> of World Heritage places is incredibly diverse. Each site represents the culture, nature and history of this land, in its own way. </p>
<p>But climate change threatens these sites. Many heritage values are already being eroded. On-ground managers of these and other protected places need practical guidance on how to understand these impacts and respond effectively. </p>
<p>We developed a <a href="https://www.dcceew.gov.au/parks-heritage/heritage/publications/climate-change-toolkit-world-properties">climate change “toolkit” for World Heritage properties</a> with site managers and Traditional Owners. To our knowledge, it is the first time such guidance has been co-developed and tested with World Heritage property managers and Indigenous experts in this country.</p>
<p>Bringing climate science and Indigenous knowledge systems together promises to produce better results for heritage protection as the climate changes. And there is no time to waste. We must act fast to address these threats to Australia’s unique and special places of global significance, so their World Heritage values can be enjoyed for generations to come.</p>
<h2>Mounting climate threats to heritage</h2>
<p><a href="https://doi.org/10.1016/j.biocon.2024.110459">Our new research</a> explored climate impacts at three very different sites: </p>
<ol>
<li><a href="https://whc.unesco.org/en/list/147/">Kakadu National Park</a>, Northern Territory</li>
<li><a href="https://whc.unesco.org/en/list/1306">Australian Convict Sites</a>, scattered around the country</li>
<li><a href="https://whc.unesco.org/en/list/167/">Willandra Lakes Region</a>, southwest New South Wales.</li>
</ol>
<p>The vast tropical <a href="https://whc.unesco.org/en/list/147/">Kakadu National Park</a> is one of four Australian properties listed for both outstanding cultural and natural values. Cave paintings, rock carvings and archaeological sites date back tens of thousands of years. Tidal flats, floodplains, lowlands and plateaus provide habitat for many rare or endemic plants and animals.</p>
<p>But Kakadu is vulnerable to rising sea levels, leading to coastal erosion and saltwater entering wetlands. The region is also experiencing more extreme temperatures and heatwaves, changing fire regimes, more intense cyclones, and increasingly intense extreme rainfall events. </p>
<p>The <a href="https://whc.unesco.org/en/list/1306/">Convict Sites</a> consist of 11 properties around Australia. Fremantle Prison lies 5,500km west of Arthur’s Vale Historic Area in the east. The Old Great North Road in the north is 1,500km from the Port Arthur Historic Site in the south.</p>
<p>Many convict sites are on coasts and islands where wave action and sea level rise are increasingly damaging structures, landscapes and cultural materials. Convict sites are also vulnerable to storms and bushfires because the buildings are so old. </p>
<p>The arid <a href="https://whc.unesco.org/en/list/167/">Willandra Lakes Region</a> contains fossil remains of a series of lakes and sand formations, along with archaeological evidence of human occupation dating back 45,000–60,000 years.</p>
<p>Hot and dry conditions are causing erosion of topsoil, increasingly exposing Aboriginal cultural heritage.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Outback landscape with delicate structures at Red Top lookout, Willandra Lakes, along the large lunette formed by wind and water erosion along a dried up lake" src="https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/573669/original/file-20240206-19-5b8ppw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Climate change is exacerbating erosion at the Willandra Lakes World Heritage site.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/outback-landscape-delicate-structures-red-top-794485033">Leah-Anne Thompson, Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-change-must-be-a-catalyst-for-reform-of-the-world-heritage-system-191798">Climate change must be a catalyst for reform of the World Heritage system</a>
</strong>
</em>
</p>
<hr>
<h2>Tapping into deep knowledge</h2>
<p>We worked closely with these sites to develop and test our new toolkit.</p>
<p>An Indigenous Reference Group of Traditional Owners from a number of World Heritage sites in Australia contributed their expert knowledge. This includes practical guidance such as how to engage with and enable Indigenous leadership so Traditional Owners can participate in or lead climate vulnerability assessment and adaptation planning. The toolkit also describes using the right knowledge for the right Country (showing respect for traditional knowledge) and establishing agreements to ensure Indigenous cultural and intellectual property rights <a href="https://www.un.org/development/desa/indigenouspeoples/publications/2016/10/free-prior-and-informed-consent-an-indigenous-peoples-right-and-a-good-practice-for-local-communities-fao/">are protected</a>.</p>
<p>Effectively addressing climate impacts on World Heritage values requires the deep knowledge, values and worldviews of <a href="https://lcipp.unfccc.int/">Indigenous Peoples and local communities</a>. This includes practices such as cultural burning to reduce the risk of intense bushfire, or cultural knowledge of long-term changes in water cycles. Tapping into this deep understanding of <a href="https://doi.org/10.1038/s41893-023-01153-1">connections between nature and culture</a> can help support the management of spiritual, living landscapes. </p>
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<h2>Adapting to climate change</h2>
<p>World Heritage site managers can take a broad range of practical actions to adapt to climate change. </p>
<p>These actions, such as firefighting or invasive species control, may not be new. They just need to be undertaken more often or intensely. </p>
<p>Other variations on existing actions may include greater emphasis on physical separation between flammable vegetation and assets such as larger firebreaks, or responding to new invasive species, possibly including shifting ranges of invasive native species. </p>
<p>Some new management actions will be required, such as flood protection, relocating assets and new technological interventions. In cases where climate change is likely to lead to changes in the values of a site, there may be a need to reevaluate management objectives and strategies (such as accommodating new groups of organisms or “ecological communities”, letting some populations decline, and managed retreat of shorelines). </p>
<p>There may also be a need to consider vulnerability at different scales, sometimes across larger areas. In some cases, managers may aim to retain certain values across a wider landscape while accepting local change.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Photo of Darlington, a convict site on Maria Island, Tasmania, take from some distance away to show all of the buildings together, with trees in the foreground and background" src="https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/573684/original/file-20240206-17-l01akv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Darlington, on Maria Island, Tasmania, is one of 11 properties grouped together under the Australian Convict Sites World Heritage listing.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/darlington-historic-settlement-on-maria-island-247616818">David Lade, Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-adaptation-projects-sometimes-exacerbate-the-problems-they-try-to-solve-a-new-tool-hopes-to-correct-that-213969">Climate adaptation projects sometimes exacerbate the problems they try to solve – a new tool hopes to correct that</a>
</strong>
</em>
</p>
<hr>
<h2>Looking ahead</h2>
<p>Managers, stakeholders and rights-holders of World Heritage sites and other protected places, such as <a href="https://www.dcceew.gov.au/water/wetlands/australian-wetlands-database/australian-ramsar-wetlands">Ramsar wetlands</a> and <a href="https://www.dcceew.gov.au/sites/default/files/documents/nrsmpa-protect.pdf">marine protected areas</a>, can now use the toolkit to plan for current and future climate threats. They can focus on the parts most useful to them, depending on their capacity and needs. Ultimately, this resource will help protect Australia’s cultural and natural heritage.</p>
<hr>
<p><em>The following people were members of the Indigenous Reference Group and are coauthors of our research paper: Bianca McNeair, Lance Syme, Chrissy Grant, Nicholas Pedrocchi, Patricia Oakley, Amy Stevens, Denis Rose, Erin Rose, Jade Gould, John Locke and Lynda Maybanks.</em></p><img src="https://counter.theconversation.com/content/222393/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jess Melbourne-Thomas received funding for this work from the Australian Commonwealth Department of Climate Change, Energy, the Environment and Water. </span></em></p><p class="fine-print"><em><span>Brenda Lin received funding for this work from the Australian Commonwealth Department of Climate Change, Energy, the Environment and Water.</span></em></p><p class="fine-print"><em><span>Lance Syme is Principal Archaeologist at Kayandel Archaeological Services, providing cultural heritage and archaeological consulting services throughout New South Wales. He is now working part-time for the International Indigenous Peoples Forum on World Heritage. Funding for the work described in this article came from the Australian Commonwealth Department of Climate Change, Energy, the Environment and Water. </span></em></p><p class="fine-print"><em><span>Mandy Hopkins received funding for this work from the Australian Commonwealth Department of Climate Change, Energy, the Environment and Water. This led to further support for vulnerability assessments from Budj Bim world heritage property management. </span></em></p>Researchers, managers and Traditional Owners are joining forces to understand and combat climate threats to Australia’s many unique World Heritage sites.Jess Melbourne-Thomas, Transdisciplinary Researcher & Knowledge Broker, CSIROBrenda Lin, Principal research scientist, CSIROLance Syme, Secretariat at the International Indigenous Peoples Forum on World Heritage, Indigenous KnowledgeMandy Hopkins, Adjunct industry fellow, University of Southern QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2211212024-01-17T04:10:46Z2024-01-17T04:10:46ZHow rising sea levels will affect our coastal cities and towns<p>Sea-level rise – along with <a href="https://www.csiro.au/en/news/All/News/2024/January/Expert-commentary-2023-warmest-year-on-record">increasing temperatures</a> – is one of the clearest signals of man-made global warming. Yet exactly how rising water levels affect the coast is often misunderstood. </p>
<p>A new <a href="https://www.marineandcoasts.vic.gov.au/coastal-programs/port-phillip-bay-coastal-hazard-assessment">coastal hazard assessment</a> for Victoria’s Port Phillip Bay has again thrown the spotlight on the impact of sea-level rise on coastal communities in Australia. Should we be worried? Or is the reality more nuanced?</p>
<p>While there are still many uncertainties, even a small change in sea level can have big impacts. We should be doing all we can to limit sea-level rise to protect our coastal cities and towns. And because sea levels will continue to rise for centuries after we cut emissions to net zero, planning decisions for coastal areas must factor this in.</p>
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<h2>Why are sea levels rising?</h2>
<p>Global sea levels are rising for two main reasons: the <a href="https://theconversation.com/ocean-heat-is-off-the-charts-heres-what-that-means-for-humans-and-ecosystems-around-the-world-207902">oceans are getting warmer</a>, and land-based <a href="https://theconversation.com/rising-seas-and-melting-glaciers-these-changes-are-now-irreversible-but-we-have-to-act-to-slow-them-down-165527">ice sheets and glaciers are melting</a>. </p>
<p>As ocean water warms, it expands. Because the ocean basins are finite (like a bathtub), this results in a rise in water levels. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ocean-heat-is-off-the-charts-heres-what-that-means-for-humans-and-ecosystems-around-the-world-207902">Ocean heat is off the charts – here's what that means for humans and ecosystems around the world</a>
</strong>
</em>
</p>
<hr>
<p>Since the 1970s, thermal expansion of the oceans has accounted for roughly <a href="https://www.climate.gov/news-features/understanding-climate/climate-change-global-sea-level">half of measured global sea-level rise</a>. The other half is due to land-based ice melt from ice sheets and glaciers. Together, these make up what is known as “eustatic” sea level.</p>
<p>The rate of sea-level rise experienced at the coast also depends on whether the land is moving up or down. “Relative” or “isostatic” sea level is the sum of “eustatic” sea level plus local vertical land movement. </p>
<p>Australia is rising by about 0.3-0.4 millimetres a year due to <a href="https://www.cmar.csiro.au/sealevel/sl_impacts_sea_level.html">glacial isostatic adjustment</a>. This is the result of the land continuing to move upward following the loss of ice on land during <a href="https://www.sciencedirect.com/science/article/abs/pii/B978044453447700074X">previous glaciations</a>. The land subsided under the weight of this ice and is now rebounding as the ice is gone. This slow rebound of the land provides a small offset to eustatic sea levels around Australia.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/rising-seas-and-melting-glaciers-these-changes-are-now-irreversible-but-we-have-to-act-to-slow-them-down-165527">Rising seas and melting glaciers: these changes are now irreversible, but we have to act to slow them down</a>
</strong>
</em>
</p>
<hr>
<h2>Sea-level rise is accelerating</h2>
<p>From 1900 to 2018, global sea levels rose by <a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter02.pdf">about 20cm</a> (a long-term average of 1.7mm/yr), but almost everywhere the rate of rise is increasing. Measurements since 1993, when global satellite data became available, show the rate of global mean sea-level rise over the past decade has more than doubled to <a href="https://www.nature.com/articles/s41467-021-21265-6">more than 4mm/yr</a>.</p>
<p>Around Australia, sea levels are rising at or above this global average. <a href="http://www.bom.gov.au/oceanography/projects/abslmp/abslmp.shtml">Tide gauges</a> indicate the rate of rise in northern Australia since the early 1990s is around 4–6mm/yr. Along the south-east coast of Australia, it’s about 2–4mm/yr. Rates of sea-level rise are not uniform around Australia because of local effects like ocean circulation and tidal processes. </p>
<p>Even if greenhouse gas emissions reached zero tomorrow, sea levels will continue to rise for several centuries because of the slow response of the ocean to warming. It’s a long-term trend that we must live with. </p>
<p>This is why is it important to factor in sea-level rise when we make planning decisions along the coast. Unfortunately, the rate of sea-level rise over the coming century remains highly uncertain, making it difficult to include in coastal planning.</p>
<p>The “likely” range of the most recent projections by the Intergovernmental Panel on Climate Change (<a href="https://www.ipcc.ch/">IPCC</a>) is a rise of <a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter09.pdf">between 0.4 metres and 0.8m</a> by 2100. However, a rise of nearly 2m by 2100 and 5m by 2150 cannot be ruled out. This is due to deep uncertainty about ice-sheet processes – so much so, that in 2021 the IPCC introduced a new <a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter09.pdf">high-end risk scenario</a> to describe this.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/coastal-property-prices-and-climate-risks-are-both-soaring-we-must-pull-our-heads-out-of-the-sand-195357">Coastal property prices and climate risks are both soaring. We must pull our heads out of the sand</a>
</strong>
</em>
</p>
<hr>
<h2>Small rises have big impacts</h2>
<p>The impact of sea-level rise at the coast is not just a gradual increase in water lapping at the shore. An increase in tide heights (both higher high tides and higher low tides) increases the probability of coastal flooding and erosion when storms come along.</p>
<p>As a rule of thumb, every 10cm of sea-level rise <a href="https://theconversation.com/climate-explained-why-coastal-floods-are-becoming-more-frequent-as-seas-rise-127202#">triples the frequency</a> of a given coastal flood. Another rule of thumb, known as the <a href="https://nccarf.edu.au/wp-content/uploads/2019/05/Rules-of-thumb-for-managing-coastal-processes.pdf">Bruun Rule</a>, suggests a 1cm rise in sea level leads to a 1m retreat of the coastline.</p>
<p>While these back-of-the-envelope estimates are often <a href="https://www.nature.com/articles/s41558-020-00934-2">significantly reduced when local conditions are accounted for</a>, it explains why a small shift in the mean sea level can have big impacts at the coast.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-explained-why-coastal-floods-are-becoming-more-frequent-as-seas-rise-127202">Climate explained: why coastal floods are becoming more frequent as seas rise</a>
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</em>
</p>
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<h2>Storms aren’t always bad for the beach</h2>
<p>Most of the impacts of sea-level rise around Australia’s coast will be felt in combination with storm events, such as <a href="https://www.abc.net.au/news/2020-02-07/what-is-an-east-coast-low-wild-weekend-weather/11936190">east coast lows</a> or <a href="https://www.abc.net.au/news/2011-02-01/tropical-cyclones-explained/1926870">tropical cyclones</a>. A high water level plus a storm surge on top leads to a storm or “king” tide. In combination with storm waves, it can cause significant coastal erosion and flooding. </p>
<p>However, storms also bring sand from deeper water towards the beach. Over the long term, this process <a href="https://www.nature.com/articles/s43247-022-00437-2">can help beaches keep pace with sea-level rise</a>. Fortunately for eastern Australia, we have a lot of sand sitting offshore which is <a href="https://www.sciencedirect.com/science/article/abs/pii/S002532271630010X?via%3Dihub">slowly making its way back to our beaches</a>. Other naturally regressive coastlines, such as many in Northern Europe, are not so lucky.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/become-a-beach-scientist-this-summer-and-help-monitor-changing-coastlines-214307">Become a beach scientist this summer and help monitor changing coastlines</a>
</strong>
</em>
</p>
<hr>
<h2>All eyes on Antarctica</h2>
<p>Sea-level rise is here to stay and gathering pace, but the rate of future increase remains uncertain. It largely depends on what happens in Antarctica over the coming decades. </p>
<p>This in turn depends on land and sea temperatures around the southern continent, which are directly linked to our efforts to limiting global warming to 1.5°C in line with the <a href="https://unfccc.int/process-and-meetings/the-paris-agreement">Paris Agreement</a>. </p>
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<p>With over 250 million people now living on land <a href="https://www.nature.com/articles/s41467-021-23810-9">less than 2m above sea level</a>, most in Asia, it is imperative we do everything we can to limit future sea-level rise.</p><img src="https://counter.theconversation.com/content/221121/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Thomas Mortlock works as a senior analyst for Aon Reinsurance Solutions Australia.</span></em></p>Even a small rise in sea level can have big impacts on coastal properties, so we must do all we can to limit the changes while taking them into account in coastal land-use planning.Thomas Mortlock, Adjunct Fellow, Climate Change Research Centre, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2143072024-01-04T20:01:53Z2024-01-04T20:01:53ZBecome a beach scientist this summer and help monitor changing coastlines<figure><img src="https://images.theconversation.com/files/565647/original/file-20231213-17-zlgqzp.jpg?ixlib=rb-1.1.0&rect=35%2C11%2C3958%2C2257&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">CoastSnap</span></span></figcaption></figure><p>When you arrive at your favourite beach these summer holidays, you may notice something different about the coast. </p>
<p>With the triple-dip La Niña now <a href="https://media.bom.gov.au/releases/1205/the-bureau-forecasts-an-unusually-warm-summer/">making way for El Niño</a>, our beaches have been through a rollercoaster ride. Some beaches have been completely stripped of sand, while others have grown very wide. </p>
<p>In the past, such changes went mostly unrecorded. However, thanks to a project <a href="https://www.coastsnap.com/">known as CoastSnap</a>, coastal data is now being collected like never before. Using designated camera cradles installed at beach viewpoints, CoastSnap uses community snapshots taken on smartphones to track beach change. </p>
<p>Almost <a href="https://www.spotteron.com/coastsnap/">50,000 photos</a> have been collected so far. They have revealed a varying picture in recent years: from <a href="https://www.abc.net.au/news/2020-02-12/tropical-cyclone-uesi-bring-dangerous-conditions-nsw-coast/11955628">dramatic beach loss during La Niña storms three years ago</a>, to <a href="https://www.smh.com.au/environment/climate-change/the-sydney-beach-that-s-grown-by-59-metres-since-last-summer-20230921-p5e6id.html">60 metres of beach growth in recent months</a>. So with smartphones as commonplace as towels and sunscreen in the beach bag, why not add coastal data collection to your list of holiday activities this summer?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="CoastSnap stainless steel camera cradle with smartphone placed in it, overlooking Manly beach" src="https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/563079/original/file-20231203-29-n4laod.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A CoastSnap community beach monitoring station at Manly Beach in Sydney, Australia.</span>
<span class="attribution"><span class="source">Larry Paice</span></span>
</figcaption>
</figure>
<h2>Turning beach snaps into scientific data</h2>
<p>Through CoastSnap, we installed a network of stainless-steel camera cradles along coastal trails all around the world. These camera cradles are positioned at a perfect vantage point for tracking changes to the coast – whether it be due to rising sea levels, extreme storms or other factors.</p>
<p>All you need to do is place your camera in the cradle, take a photo and upload it using the QR code at the station. Because the position and angle of the photo is always the same, over time these snaps reveal how the beach is changing.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/millions-of-satellite-images-reveal-how-beaches-around-the-pacific-vanish-or-replenish-in-el-nino-and-la-nina-years-198505">Millions of satellite images reveal how beaches around the Pacific vanish or replenish in El Niño and La Niña years</a>
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</em>
</p>
<hr>
<p>As well as being a powerful visual record, <a href="https://www.sciencedirect.com/science/article/pii/S0278434322001492">sophisticated algorithms</a> turn each photo into miniature satellite images that are used to precisely measure shoreline position. This is done using a <a href="https://en.wikipedia.org/wiki/Photogrammetry">process known as photogrammetry</a>, in which pixels in the image are rearranged as though they had been taken from space. </p>
<p>This aerial view enables beach change to be easily measured. Also, since the exact time of photo capture is recorded, the effects of tides as they vary throughout the day can be accounted for.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="CoastSnap photo of beach (left) and equivalent photo converted to an aerial photo with a red line to mark out the shoreline" src="https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=317&fit=crop&dpr=1 600w, https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=317&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=317&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=398&fit=crop&dpr=1 754w, https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=398&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/563240/original/file-20231204-17-8678xw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=398&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">CoastSnap photos are converted to a miniature satellite image using a process known as photogrammetry.</span>
<span class="attribution"><span class="source">Mitchell Harley</span></span>
</figcaption>
</figure>
<h2>From local to global: a network of community beach monitoring</h2>
<p>From its beginnings on the Northern Beaches of Sydney in 2017, new CoastSnap stations have been rolled out all around the world. We now have more than 350 CoastSnap stations in 31 countries and across five continents. </p>
<p>This makes it the largest coordinated network of coastal monitoring worldwide – and all the data is collected by the community.</p>
<p>In Ghana, West Africa, students from local schools are using CoastSnap to <a href="https://theconversation.com/ghanas-fishing-industry-has-a-golden-seaweed-problem-how-citizen-science-can-help-203007">better understand how the “golden seaweed” sargassum impacts fishing communities</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/like-20-tip-trucks-pouring-sand-on-every-metre-wide-strip-how-extreme-storms-can-replenish-beaches-not-just-erode-them-182039">‘Like 20 tip trucks pouring sand on every metre-wide strip’: how extreme storms can replenish beaches, not just erode them</a>
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</em>
</p>
<hr>
<p>On Prince Edward Island in Canada, CoastSnap captured the <a href="https://www.cbc.ca/news/canada/prince-edward-island/pei-fiona-coastal-climate-change-1.6599408">damage done by Hurricane Fiona last year</a>. The same stations are now being used to track the post-hurricane dune recovery.</p>
<p>In Australia, there are currently 125 CoastSnap stations around the country. This enables a big-picture assessment of the coastal consequences of large-scale weather events. For example, during <a href="https://theconversation.com/the-east-coast-rain-seems-endless-where-on-earth-is-all-the-water-coming-from-178316">last year’s record rainfall in eastern Australia</a>, extreme erosion was observed at CoastSnap stations from Queensland to southern New South Wales. The images reveal scouring by floodwaters was the main cause of beach erosion in many locations, rather than wave action as is usually the case.</p>
<p><div data-react-class="TiktokEmbed" data-react-props="{"url":"https://www.tiktok.com/@coastsnap/video/7192798251588898049"}"></div></p>
<h2>Monitoring the present to plan for the future</h2>
<p>Data on coastal change is crucial for managing coastlines into the future. This is particularly important as sea levels continue to rise, storm tracks shift, and beaches come under increasing pressure from overdevelopment.</p>
<p>With several CoastSnap stations already operating for over six years now, this growing record is beginning to observe longer-term changes to the coast. This data is being fed into numerical models that help coastal researchers predict what the coastline will be like in the coming decades – and plan accordingly.</p>
<p>Smart coastal planning will help buffer climate change impacts. This will go some way to ensure future generations can enjoy the coast like we do today. </p>
<p>So as you head out to the beach this summer, look out for your nearest CoastSnap station and help monitor the coastline – it really is a “snap”!</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/storms-or-sea-level-rise-what-really-causes-beach-erosion-209213">Storms or sea-level rise – what really causes beach erosion?</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/214307/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mitchell Harley receives funding from the Australian Research Council. He is also the New South Wales Chair of the Australian Coastal Society.</span></em></p><p class="fine-print"><em><span>Fred Chaaya works for the University Of New South Wales Water Research Laboratory, which manages the CoastSnap project and network.</span></em></p>With smartphones as commonplace as towels and sunscreen in the beach bag, why not add coastal data collection to your list of holiday activities this summer? Look for the CoastSnap camera cradles.Mitchell Harley, Scientia Senior Lecturer, UNSW SydneyFred Chaaya, Project Engineer, UNSW Water Research LaboratoryLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2196612023-12-20T16:05:46Z2023-12-20T16:05:46ZUK government facing legal action for failing to tackle climate change – but it could backfire<p>The parish of Whimpell once stood on the Norfolk coast between the village of Happisburgh and the sea. Whimpell <a href="https://www.bgs.ac.uk/case-studies/coastal-erosion-at-happisburgh-norfolk-landslide-case-study/">disappeared into the sea</a> centuries ago thanks to coastal erosion. And now Happisburgh is facing a <a href="https://www.bbc.co.uk/news/uk-england-norfolk-63822899">similar threat</a>.</p>
<p>Some, however, do not intend to give up without a fight. On October 17 2023, <a href="https://climatecasechart.com/wp-content/uploads/non-us-case-documents/2023/20231101_21608_complaint.pdf">a case was brought</a> against the UK government by <a href="https://www.theguardian.com/environment/2023/nov/01/claimants-take-uk-government-to-court-over-inadequate-climate-adaptation">two people</a> supported by Friends of the Earth, an environmental charity. </p>
<p>The first is Kevin Jordan, whose home is at risk due to coastal erosion in Hemsby, Norfolk. The second is Doug Paulley of Wetherby in west Yorkshire, who suffers from a number of medical issues that make him particularly vulnerable to the increased frequency and intensity of extreme heat.</p>
<p>Only a <a href="https://climatecasechart.com/non-us-case/rfriends-of-the-earth-ltd-mr-kevin-jordan-and-mr-doug-paulley-v-secretary-of-state-for-environment-rood-rural-affairs-challenge-to-the-third-national-adaptation-programme/">summary</a> of the claims has been made available publicly. But it is clear that the claimants are focusing on the UK’s most recent <a href="https://www.gov.uk/government/publications/third-national-adaptation-programme-nap3">national adaptation programme</a> (NAP3). The NAP3 outlines the actions the government and others will take to adapt to the effects of climate change from 2023 to 2028. </p>
<p>The claimants argue that the NAP3 is not sufficiently ambitious and specific. It is also argued that there is no evidence that an appropriate assessment of the risks posed by climate change has been conducted, and that the unequal impact on protected groups has not been considered. </p>
<p>The claimants add that the government has failed to protect a number of <a href="https://www.legislation.gov.uk/ukpga/1998/42/contents">human rights</a>, including the rights to property, life, respect to private and family life, and the prohibition of discrimination.</p>
<figure class="align-center ">
<img alt="Crumbling cliffs at Happisburgh on the Norfolk coast." src="https://images.theconversation.com/files/566066/original/file-20231215-27-m57r9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566066/original/file-20231215-27-m57r9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566066/original/file-20231215-27-m57r9a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566066/original/file-20231215-27-m57r9a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566066/original/file-20231215-27-m57r9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566066/original/file-20231215-27-m57r9a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566066/original/file-20231215-27-m57r9a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Happisburgh in Norfolk has lost a lot of land to the sea.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/crumbling-cliffs-sea-erosion-happisburgh-on-417847936">Helen Hotson/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Legality of the claims</h2>
<p>The preparation of the national adaption programme is required by <a href="https://www.legislation.gov.uk/ukpga/2008/27/section/58">section 58</a> of the UK <a href="https://www.legislation.gov.uk/ukpga/2008/27/contents">Climate Change Act 2008</a>. This article demands that the NAP3 sets out the objectives of the UK in relation to adaptation, as well as proposals for meeting these objectives.</p>
<p>However, section 58 does not explicitly require the government to take specific, ambitious action on adaptation to the impacts of climate change. The only indication in this law concerning the level of ambition that national adaption programmes should achieve is that adaptation objectives, proposals and policies “must be such as to contribute to sustainable development”. </p>
<p>There is no doubt that a progressive interpretation of the Climate Change Act may set an important precedent in relation to government obligation to actively adopt adaptation measures. The court, for example, may accept that the instruction that the NAP3 will “contribute to sustainable development” means that the government is obliged to adopt ambitious and specific adaptation measures, such as those requested by the claimants. </p>
<p>At the same time, it is also possible the court will understand this instruction in a very limited manner. For example, the court may clarify that the obligation to adopt adaptation measures is entirely within the discretion of the government and therefore, to put it bluntly, the government can do as it pleases. This is not an unlikely prospect given the High Court’s <a href="https://www.judiciary.uk/wp-content/uploads/2022/07/FoE-v-BEIS-judgment-180722.pdf">earlier narrow interpretation</a> of “sustainable development”.</p>
<p>The human rights arguments made by the claimants are clearer and simpler to understand. The fact that this case focuses on the government’s obligation to adapt to, rather than mitigate, climate change makes it easier to prove. The claimants don’t have to demonstrate that the UK government caused harm to their human rights, only that it has failed to protect them from the impacts of climate change.</p>
<h2>A growing trend</h2>
<p>This case is hardly a unique effort but rather part of a wider and growing trend of <a href="https://climatecasechart.com/">climate litigation</a> targeting both states and companies. Globally, hundreds of cases have been brought against states in the past two decades, with <a href="https://climatecasechart.com/non-us-jurisdiction/united-kingdom/">103</a> of them occurring in the UK.</p>
<p>A somewhat similar litigation – <a href="https://climatecasechart.com/non-us-case/union-of-swiss-senior-women-for-climate-protection-v-swiss-federal-council-and-others/">KlimaSeniorinnen v Switzerland</a> – is also currently before a different tribunal: the European Court of Human Rights. In this instance, a group of elderly citizens are claiming that the impacts of climate change are affecting certain human rights, including their right to life due to (among other things) climate change-related heatwaves. </p>
<p>The current UK case offers a glimpse into the potential benefits and risks that are involved in this strategy. The benefits are clear. The case has already been reported by leading media outlets and is being discussed by academics. </p>
<p>Winning the case and forcing the government to act on climate change could yet be another potential win, albeit an uncertain one given the record of climate litigation in the UK. While there have been a few celebrated cases, the vast majority of UK cases have been rejected.</p>
<p>The risks of climate litigation are equally clear. The court may clarify the meaning of the law – <a href="https://climatecasechart.com/non-us-case/r-finch-v-surrey-county-council/">as it has done before</a> – in a manner that those supportive of environmental action will not approve of. </p>
<p>This same risk exists in the current case. The court may limit the link between the impacts of climate change and human rights, or clarify that adaptation plan objectives could be as limited as the government wishes them to be.</p>
<p>To what extent this type of legal action will help tackle climate change in the UK remains to be seen. Given the risks discussed above, one may also question whether these cases bring more good than harm. But it’s a global phenomenon that shows no sign of stopping any time soon.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
<br><em><a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeTop">Get a weekly roundup in your inbox instead.</a> Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. <a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeBottom">Join the 30,000+ readers who’ve subscribed so far.</a></em></p>
<hr><img src="https://counter.theconversation.com/content/219661/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Can we avoid dangerous climate change by taking government to court?Avidan Kent, Senior Lecturer in Law, University of East AngliaIrene Lorenzoni, Professor of Society and Environmental Change, University of East AngliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2173532023-11-16T22:57:51Z2023-11-16T22:57:51ZLet coastlines be coastlines: How nature-based approaches can protect Canada’s coasts<p>Along Canadian coasts, <a href="https://www.queensu.ca/gazette/stories/climate-change-means-atlantic-canada-will-see-more-frequent-storms">storm surges</a> and <a href="https://www.uottawa.ca/environment/blog/100-year-floods-are-increasing-canada-due-climate-change-officials-say-true">flooding</a> have gone from breaking news to seasonal norms. </p>
<p>Phenomena Canadians have historically thought of as freak <a href="https://doi.org/10.1080/24694452.2020.1744423">natural disasters are becoming regular predictable occurrences</a>. </p>
<p>Our go-to solution to protect property and infrastructure is to build walls to block wave energy — walls that have become <a href="https://www.researchgate.net/profile/Ca-Vu/publication/346517536_Coastal_Development_Resilience_Restoration_and_Infrastructure_Requirements_LEAD_AUTHORS_About_the_High_Level_Panel_for_a_Sustainable_Ocean_Economy/links/5fc5e73992851c3012995ca6/Coastal-Development-Resilience-Restoration-and-Infrastructure-Requirements-LEAD-AUTHORS-About-the-High-Level-Panel-for-a-Sustainable-Ocean-Economy.pdf">ineffective and unaffordable</a>. It’s time to look beyond the status quo and consider <a href="https://www.csagroup.org/article/research/nature-based-solutions-for-coastal-and-riverine-flood-and-erosion-risk-management/">nature-based solutions</a> to protect the places we love.</p>
<h2>How we got here</h2>
<p>In many parts of the world, humans have long felt a <a href="https://press.uchicago.edu/ucp/books/book/chicago/H/bo14312647.html">strong connection to the coast</a>. We <a href="https://doi.org/10.1016/B978-0-323-95227-9.00007-5">write stories, sing songs and build lives</a> on the lands that touch the sea. We also build walls and other concrete, stone and metal structures to <a href="https://oceanservice.noaa.gov/facts/shoreline-armoring.html">protect those lands</a> from the very seas we revere.</p>
<p>From time immemorial, Indigenous Peoples made their homes along the coasts, becoming <a href="https://pressbooks.bccampus.ca/knowinghome/chapter/chapter-7/">experts in their knowledge</a> of coastal ecosystems and, on the Atlantic and Pacific coasts, used <a href="https://www.ubcpress.ca/against-the-tides">salt marshes for food and transportation</a>. Following European settlement, those salt marshes were drained, <a href="https://www2.gov.bc.ca/gov/content/environment/air-land-water/water/drought-flooding-dikes-dams/integrated-flood-hazard-management/dike-management#:%7E:text=Dike%20consequence%20classification-,History%20of%20dikes%20in%20B.C.,relatively%20little%20damage%20was%20caused.">dykes</a> were built from earth and wood, and the land was cultivated for agriculture.</p>
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Read more:
<a href="https://theconversation.com/storms-or-sea-level-rise-what-really-causes-beach-erosion-209213">Storms or sea-level rise – what really causes beach erosion?</a>
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<p><a href="https://books.google.ca/books?hl=en&lr=&id=AjwPEAAAQBAJ&oi=fnd&pg=PP1&dq=how+much+of+Canada%27s+coast+is+hardened+shoreline&ots=ofxRgZFp1q&sig=pudIoHph4rwpz4E5hntGfVx36uc#v=onepage&q=how%20much%20of%20Canada's%20coast%20is%20hardened%20shoreline&f=false">Over time, other hard armour structures</a> such as <a href="https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/agriculture-and-seafood/agricultural-land-and-environment/water/drainage-management-guide/533410-1_rock_revetments-drainage_guide_factsheet_no12.pdf">revetments</a> and <a href="https://www.britannica.com/technology/breakwater">breakwaters</a> were constructed to block wave energy and provide additional protection for agriculture, transportation and growing cities.</p>
<h2>Where we are now</h2>
<p>Today, Canada’s coastal infrastructure includes extensive networks of seawalls, dykes, revetments and breakwaters, most of which are made of hard materials. Hard coastal infrastructure is everywhere if you know where to look. The <a href="https://transcanadahighway.com/nova-scotia/canso-causeway/">Canso Causeway</a> connecting Cape Breton Island to mainland Nova Scotia and the <a href="https://vancouver.ca/parks-recreation-culture/seawall.aspx">Vancouver seawall</a> are just two examples. </p>
<p>In some cases, using <a href="https://www.jstor.org/stable/48703231?seq=2">hard infrastructure</a> is unavoidable. Indeed, <a href="https://nrc.canada.ca/en/research-development/research-collaboration/programs/ocean-program-coastal-resilience-technology-theme">hard infrastructure</a> is critical for maintaining transportation and energy infrastructure, including roads, railroads and ports. </p>
<p>However, hard infrastructure almost always <a href="https://www.intactcentreclimateadaptation.ca/rising-seas-and-shifting-sands-combining-natural-and-grey-infrastructure-to-protect-canadas-eastern-and-western-coastal-communities/">increases erosion</a> in adjacent areas, is expensive to maintain and degrades over time. Engineers predict that repairs, including <a href="https://www2.gnb.ca/content/dam/gnb/Departments/trans/Chignecto/chignecto-isthmus-project-report-e.pdf">raising the dykes along the Chignecto Isthmus</a> between New Brunswick and Nova Scotia, will cost between $189-300 million. </p>
<p>With such an astronomical price tag, even smaller projects are simply not an option for many municipalities or individual landowners.</p>
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Read more:
<a href="https://theconversation.com/coastal-erosion-is-unstoppable-so-how-do-we-live-with-it-186365">Coastal erosion is unstoppable – so how do we live with it?</a>
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<p>In the face of such challenges, there are opportunities to adapt engineering and protective infrastructure to be more sustainable by integrating natural elements and processes.</p>
<h2>Nature-based solutions</h2>
<p><a href="https://www.transcoastaladaptations.com/nature-based-climate-change-adaptation">Nature-based approaches</a> preserve or reintroduce natural structures and materials into the environment, recognizing and respecting natural systems and their benefits for humans. </p>
<p>Nature-based approaches range from those that are entirely natural to hybrid solutions, which incorporate traditional hard engineering with natural features.</p>
<p>Examples of nature-based solutions <a href="https://static1.squarespace.com/static/5c83d5c63560c33561cc74de/t/61aeca0bf994d4620c5aba87/1638844941547/MRfM_BelcherStMarsh_Case_Study_Final__Dec_05_21_Updated.pdf">include</a> dyke realignment to restore natural water flow and allow saltmarsh reestablishment, wetland and dune restoration, and living shorelines which utilize plants, sand and rock to protect the coast. </p>
<p>Nature-based approaches can involve <a href="https://doi.org/10.1016/j.nbsj.2022.100044">reserving land for natural systems by protecting them from development</a> and making room for the evolution of natural systems; they can also <a href="https://doi.org/10.1016/j.landusepol.2021.105960">involve moving back from the coast, and releasing land back to nature</a>.</p>
<p>Hard infrastructure weakens over time while nature-based solutions grow stronger as plants establish roots, biodiversity increases and natural processes adjust. </p>
<p>Nature-based solutions provide a wide array of benefits. In addition to protecting coastal places from flooding, storm surges and erosion. Nature-based solutions <a href="http://stewardshipcentrebc.ca/PDF_docs/greenshores/Resources/Green%20Shores%202020_%20Impact,%20Value%20and%20Lessons%20Learned_%20Full%20Report_July2020.pdf">prevent shoreline pollution</a>, <a href="https://www.mdpi.com/2071-1050/10/2/523/htm">support biodiversity</a>, can <a href="http://stewardshipcentrebc.ca/PDF_docs/greenshores/Resources/Green%20Shores%202020_%20Impact,%20Value%20and%20Lessons%20Learned_%20Full%20Report_July2020.pdf">increase property value</a> and contribute to overall <a href="https://doi.org/10.3390/su131910950">human well-being</a>. </p>
<p>Incorporating nature-based solutions requires innovation and open-mindedness that may feel intimidating and it is often <a href="https://web.archive.org/web/20220329065340id_/https:/nhess.copernicus.org/preprints/nhess-2022-104/nhess-2022-104.pdf">easier to trust a stone or concrete wall</a> over the energy absorbing power of plants and soil. </p>
<p>As such, <a href="https://doi.org/10.1016/j.nbsj.2022.100044">raising awareness</a> about different nature-based options and being transparent about <a href="https://doi.org/10.1098%2Frstb.2019.0120">costs and benefits</a> can help build confidence in nature-based solutions. </p>
<p>Successful nature-based solutions also require place-based <a href="https://web.archive.org/web/20220329065340id_/https:/nhess.copernicus.org/preprints/nhess-2022-104/nhess-2022-104.pdf">collaboration and knowledge sharing</a> between impacted peoples, engineers, scientists and decision-makers that consider social
and ecological interests. </p>
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<strong>
Read more:
<a href="https://theconversation.com/st-lawrence-shoreline-erosion-we-must-work-with-not-against-nature-184721">St. Lawrence shoreline erosion: We must work with, not against, nature</a>
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<p><a href="https://royalsociety.org/topics-policy/projects/biodiversity/nature-based-solutions/">Nature-based solutions cannot be prescribed as top-down interventions</a>. Every situation is unique, and many people with diverse knowledge and perspectives should come together to decide how specific nature-based approaches can meet various infrastructure, ecological and social needs as well as increase flood resilience.</p>
<h2>What now?</h2>
<p>For natural resource and permitting agencies, as well as many property owners, the tradition of building hard armoured shorelines remains deeply ingrained. Current guidance documents, policies and habits were built for hard infrastructure. In some cases, <a href="https://doi.org/10.3390/su11236735">bureaucratic decision-making structures</a> move slower than hazards from flooding. </p>
<p>In other cases, including lack of or delayed implementation of legislation, such as <a href="https://www.halifaxexaminer.ca/government/province-house/houston-government-once-again-delays-implementation-of-coastal-protection-act/">the Coastal Protection Act</a> and regulations in Nova Scotia, <a href="https://ecologyandsociety.org/vol28/iss2/art25/">political interests</a> hinder planning actions that would limit hard infrastructure and development along the coast.</p>
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<figcaption><span class="caption">An overview of the problems of erosion facing many communities across Canada, particularly in the North. Produced by the CBC.</span></figcaption>
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<p><a href="https://climatechoices.ca/wp-content/uploads/2021/09/Infrastructure-English-FINAL-Sep29.pdf?utm_source=vancouver%20is%20awesome&utm_campaign=vancouver%20is%20awesome%3A%20outbound&utm_medium=referral">Many Canadians</a> are buying homes in areas with high flood risk. The infrastructure they rely upon is <a href="https://changingclimate.ca/national-issues/chapter/2-0/">aging</a> and requires adaptation. Infrastructure supporting <a href="https://highways.dot.gov/public-roads/autumn-2021/02">bridges, roads</a> and <a href="https://doi.org/10.1016/j.nbsj.2022.100013">rail lines</a> needs to be upgraded or removed, providing opportunities to incorporate nature-based solutions.</p>
<h2>Hope for the future</h2>
<p>As we look towards what can feel like an ominous future, there are many resources for individuals or organisations seeking additional information and guidance about nature-based solutions. <a href="https://www.transcoastaladaptations.com/">TransCoastal Adaptations: Centre for Nature-based Solutions</a> is a practitioner, academic and government partnership in Nova Scotia focused on restoration, managed realignment and climate change adaptation. </p>
<p>Privately owned companies, also in Nova Scotia, <a href="https://helpingnatureheal.com/">Helping Heal Nature</a> and <a href="https://www.cbwes.com/">CB Wetlands and Environmental Specialists</a>, focus on ecological restoration, living shorelines and community stewardship and education. Nation-wide <a href="https://coastalzonecanada.org/nbcs/">communities of practice</a> exist to build capacity for natural and nature-based approaches.</p>
<p>As more people learn about nature-based solutions, there will be more opportunities to incorporate natural processes into coastal protection. We know the stakes, and we have nature-based solutions at hand. It’s time to give dirt and plants a chance.</p><img src="https://counter.theconversation.com/content/217353/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Keahna Margeson receives funding from the Ocean Frontier Institute Ocean Graduate Excellence Network, Canada First Research Excellence Fund, Social Sciences and Humanities Research Council, and National Research Council Canada. </span></em></p>As seas rise, it is clear that traditional coastal defence approaches are unable to keep pace. Nature-based solutions offer considerable potential to protect coasts, people and biodiversity.Keahna Margeson, IDPhD Student, School for Resource and Environmental Studies, Dalhousie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2127402023-11-03T17:32:50Z2023-11-03T17:32:50ZThe climate crisis is making gender inequality in developing coastal communities worse<p>Across the world, women and men experience the impacts of the climate crisis in different ways. These are shaped by societal roles and responsibilities and result in <a href="https://theconversation.com/climate-crisis-could-reverse-progress-in-achieving-gender-equality-127787">widening inequalities</a> between men and women. </p>
<p>Sea-level rise, storm surges and high waves in coastal area do not discriminate, but societal structures often do. This makes climate change a highly gender-sensitive issue.</p>
<p><a href="https://www.ipcc.ch/report/ar6/wg2/">Research</a> has long shown that coastal areas are the most directly affected by climate change. Small islands in Asia, central and South America and Africa – what many term “<a href="https://theconversation.com/the-global-south-is-on-the-rise-but-what-exactly-is-the-global-south-207959">the global south</a>” – are particularly vulnerable to land erosion and economic decline, amid livelihood losses in fisheries. </p>
<p><a href="https://environment.leeds.ac.uk/geography/pgr/11413/andi-misbahul-pratiwi">My doctoral research</a> explores how in countries where women and girls already face disproportionate inequalities relating to ethnicity, class, age and education, the climate crisis is <a href="https://theconversation.com/how-womens-environmental-action-across-the-global-south-can-create-a-better-planet-214083">making things worse</a>. In <a href="https://www.tandfonline.com/doi/full/10.1080/19480881.2010.536669">coastal areas</a>, in particular, women and girls are <a href="https://www.sciencedirect.com/science/article/abs/pii/S0959378006000422">ever more vulnerable</a>.</p>
<h2>Livelihoods under threat</h2>
<p>In 2017, in collaboration with the <a href="https://indonesianfeministjournal.org/">Indonesian Feminist Journal</a>, I conducted <a href="https://indonesianfeministjournal.org/index.php/IFJ/article/view/203/259">research</a> off the coast of Demak in Java, Indonesia. I found that women in coastal communities faced multiple problems, from poverty and <a href="https://wrd.unwomen.org/explore/insights/how-fisherwomen-java-rise-above-climate-change-and-increase-gender-based-violence">domestic and gender-based violence</a> to employment challenges. </p>
<p>Fisherwomen who work at sea are having to sail further out and contend with difficult conditions to find catches. One woman, Zarokah, <a href="https://www.youtube.com/watch?v=gzSyPW2D73o">I interviewed</a> had started fishing with her husband, two years earlier, when he could no longer find a crew to work with. They wake at 3am to head out to sea. </p>
<p>She told me a basket of tiny flying fish goes for 150,000 rupiah (£7.70) and a good haul will yield several baskets. But even when they don’t catch anything, they still have to cover the cost of supplies and equipment. <a href="https://www.thejakartapost.com/business/2022/10/24/warming-seas-bring-indonesias-fishermen-deadly-storms-empty-nets.html">This income is inadequate</a> when faced with a situation where fish are becoming scarcer and extreme weather prevents them from going out to sea.</p>
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<p><a href="https://eprints.whiterose.ac.uk/196016/">I have shown</a> how women in this area and beyond have contributed significantly to the fishing sector and coastal economies. And yet, Masnu'ah, who is the founder of a local fisherwomen’s organisation, told me that women’s economic role continues to not be recognised by their male peers and society more broadly. </p>
<p>Zarokah is still labelled a “housewife” on her ID card, despite the fact that, as she put it, “If I don’t go, my husband doesn’t go either and we cannot meet our needs.”</p>
<p>If the fisherwomen do not receive recognition for their work, they are unable to access social protections including <a href="https://www.undp.org/indonesia/news/fisherwomen-fisherman%E2%80%99s-world-improving-access-women-indonesian-fisheries">life insurance</a>. As climate change increasingly threatens the profession at large, having state support and insurance is vital. </p>
<h2>Access to amenities and healthcare</h2>
<p>It’s not just women’s livelihoods in this area that are impacted by extreme weather and any other disruptions to the fishing industry. <a href="https://www.thejakartapost.com/paper/2023/07/25/slow-disaster-residents-in-central-javas-sinking-village-forced-to-adapt.html">Tidal flooding</a> has also made it difficult for women and girls to access healthcare facilities. </p>
<p>Women find it difficult to access clinics because the roads are closed and isolated. One activist in Demak told me about helping a woman give birth in the middle of a tidal flood – when the houses were sinking. “It was very difficult,” she said, “because the waves were high, there were no boats. The baby died two to three days after.” </p>
<p>Research from other regions in the world show a similar pattern of increasing vulnerability. In the south-western coastal region of <a href="https://theconversation.com/bangladesh-is-undertaking-the-worlds-largest-resettlement-programme-and-the-climate-is-making-it-harder-208664">Bangladesh</a>, natural hazards, including storm surges and <a href="https://theconversation.com/climate-change-isnt-just-making-cyclones-worse-its-making-the-floods-they-cause-worse-too-new-research-182789">cyclones</a>, have long affected women significantly. Of the 140,000 people killed in the 1991 cyclone disaster, <a href="https://lib.icimod.org/record/13783/files/1337.pdf">90% were women</a>.</p>
<p>However, the impacts are broader than that. <a href="https://www.mdpi.com/2071-1050/15/4/3744">A recent study</a> looked at women’s lives, particularly among the ethnic Munda community, in the Khulna, Satkhira and Bagerhat districts. It found that bad management of open-water sources (ponds and canals) has led to high water salinity. Women and girls, who are responsible for family provisions, have to walk up to 3km – and sometimes as far as 5km – to find drinking water.</p>
<p>They spend long hours carrying heavy water pots, which leads to chronic pain conditions. During droughts, this task can take over three hours daily. The women and girls also face harassment from boys and men while collecting the water.</p>
<p>A 2020 study in Ilaje, a coastal region in Nigeria, found that, there too, <a href="https://www.sciencedirect.com/science/article/pii/S0959652619338855#abs0010">women and girls</a> often bear the responsibility of ensuring there’s enough food, fuel and clean water available at home. During times of low rainfall or drought, they have to cover similarly long distances. Young girls sometimes have to leave school in order to help their mothers with these tasks.</p>
<p>Pregnant women in Ilaje, particularly, are vulnerable to health effects like malnutrition, dehydration, anemia, and other health risks related to low food and water availability during crises.</p>
<p>Due to prevailing patriarchal norms, Ilaje women lack the authority to make independent decisions within their families and in society. They don’t have control over financial matters and assets. And they are not given opportunities to participate in public spaces, in particular within community group discussions on climate change adaptation. As a result, they are unable to voice their specific concerns and needs – at both family and community levels. </p>
<p>Oceans and coastal ecosystems cover over two thirds of the planet. They <a href="https://www.ipcc.ch/report/ar6/wg2/">play a crucial role</a> in food and energy production as well as creating employment opportunities. About <a href="https://sustainabledevelopment.un.org/content/documents/Ocean_Factsheet_People.pdf">600 million people</a> – around 10% of the world’s population – reside in coastal areas that are less than 10 metres above sea level. </p>
<p>The central tenet of the UN’s 2030 agenda for sustainable development is to “leave no one behind”. Applying a <a href="https://eprints.whiterose.ac.uk/196019/">feminist political lens</a> to the climate crisis is crucial to understanding how multilayered the problems facing women and girls in rural and coastal regions around the world are. </p>
<p>Yet, social and feminist research on how the climate is changing has been <a href="https://journals.sagepub.com/doi/abs/10.1111/j.1467-954X.2010.01889.x">scarce</a>. Without it, women and girls will indeed be left behind. </p>
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<p class="fine-print"><em><span>Andi Misbahul Pratiwi does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Sea-level rises and storm surges don’t discriminate, but societal structures do.Andi Misbahul Pratiwi, PhD Candidate, School of Geography, University of LeedsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2092132023-10-31T19:17:41Z2023-10-31T19:17:41ZStorms or sea-level rise – what really causes beach erosion?<figure><img src="https://images.theconversation.com/files/556735/original/file-20231030-23-2np8f3.JPG?ixlib=rb-1.1.0&rect=16%2C24%2C5447%2C3612&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">John Hudson</span></span></figcaption></figure><p>Beaches are dynamic. They change from week to week and month to month. Have you ever wondered what causes these changes? Or how beaches might fare as sea levels rise and if storms increase in frequency and severity? </p>
<p>To help answer these questions, we <a href="https://doi.org/10.1016/j.geomorph.2023.108850">studied 50 years of change</a> at Bengello Beach, near the Moruya airport on the New South Wales south coast. This is a typical beach with moderate waves and no hard infrastructure such as sea walls or houses built over dunes. The results therefore represent natural beach change over half a century. This helps us understand the natural behaviour of beaches around the world. </p>
<p>We found the main driver of coastal erosion is frequent storms of moderate intensity. These storms remove sand from the beach. This sand is generally returned within a matter of months. But what about more extreme events? </p>
<p>In the 50 years of monitoring, offshore wave buoys recorded 21 storms where maximum waves heights exceeded ten metres. That’s roughly equivalent to the height of a three-story building. These larger events cause even greater erosion, so the beach takes longer to recover.</p>
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<figcaption><span class="caption">Big wave riding at Sydney’s Wedding Cake Island, near Coogee (7NEWS, May 2023)</span></figcaption>
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Read more:
<a href="https://theconversation.com/coastal-property-prices-and-climate-risks-are-both-soaring-we-must-pull-our-heads-out-of-the-sand-195357">Coastal property prices and climate risks are both soaring. We must pull our heads out of the sand</a>
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<h2>The ‘biggest of the big’ storms</h2>
<p>Some of the largest events in the record have been particularly destructive, for example the storm in June 2016 where a <a href="https://www.smh.com.au/environment/weather/sydney-storms-narrabeencollaroy-beach-lashed-by-large-seas-20160605-gpbvvw.html">residential swimming pool washed onto the beach</a> at Narrabeen-Collaroy. Or the June 2007 event when the Pasha Bulka <a href="https://www.visitnewcastle.com.au/insider-guides/a-look-back-on-the-pasha-bulker-ship-happens">container ship broke its mooring</a> and washed up on Nobbys Beach in Newcastle. Both storms also caused substantial beach erosion at Bengello.</p>
<p>One sequence of storms stands out in the record. The successive storm events of May–June 1974 including the renowned <a href="https://www.amsa.gov.au/marine-environment/incidents-and-exercises/sygna-26-may-1974">Sygna Storm of May 1974</a>. During these two months, more than a B-double truck full of sand was cut away at every metre strip of beach (95 cubic metres of sand per metre of beach), and the shoreline moved inland farther than the length of an Olympic swimming pool (63m). </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Photo of Bengello Beach in the immediate aftermath of the May 1974 storm event, which created a vertical sand cliff in the frontal dune" src="https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548313/original/file-20230914-25-hba3sy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bengello Beach suffered erosion during the May 1974 storm event. Note the vertical sand cliff carved into the dunes by wave action.</span>
<span class="attribution"><span class="source">Roger McLean</span></span>
</figcaption>
</figure>
<p>Astonishingly, it took five and half years for the beach to recover to its previous condition after these events. The recovery was hampered by more severe storms in 1976 and 1978, which interrupted the gradual build-up of beach sand.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A chart (line graph) showing beach volume changes at Bengello Beach from 1972 to 2022. Dips or downward trends indicate beach erosion, while positive spikes or upward trends indicate beach growth." src="https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=154&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=154&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=154&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=194&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=194&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548315/original/file-20230914-23-t29kvn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=194&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Beach volume changes at Bengello Beach from 1972 to 2022. Dips or downward trends indicate beach erosion, while positive spikes or upward trends indicate beach growth.</span>
<span class="attribution"><span class="source">Thomas Oliver</span></span>
</figcaption>
</figure>
<p>No other storms in the record have had such a huge impact on the beach. Importantly, this is our only quantitative record of this event because it occurred before satellite imagery was available. Therefore it is not captured by tools such as <a href="https://theconversation.com/millions-of-satellite-images-reveal-how-beaches-around-the-pacific-vanish-or-replenish-in-el-nino-and-la-nina-years-198505">CoastSat</a> and <a href="https://maps.dea.ga.gov.au/story/DEACoastlines">Digital Earth Australia Coastlines</a>, which derive shoreline positions from more than 30 years of satellite images, and have proved so powerful in understanding recent shoreline changes. </p>
<p>But how often do the biggest storms occur? Looking into the past, <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019GL083061">research</a> suggests an erosion event of this magnitude has occurred at least one other time in the past 500 years. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/millions-of-satellite-images-reveal-how-beaches-around-the-pacific-vanish-or-replenish-in-el-nino-and-la-nina-years-198505">Millions of satellite images reveal how beaches around the Pacific vanish or replenish in El Niño and La Niña years</a>
</strong>
</em>
</p>
<hr>
<h2>Can beaches survive future sea-level rise?</h2>
<p>So how will beaches fare in a warming world where <a href="https://www.nature.com/articles/s41558-019-0531-8">sea-level rise accelerates</a> and <a href="https://www.nature.com/articles/s41467-018-08066-0">coastal storms intensify</a>?</p>
<p>This beach has sufficient sand to enable recovery after extreme storm events such as those experienced in the La Niña period of 1974–78. This degree of recovery is related to each beach’s so-called “<a href="https://theconversation.com/why-some-beaches-including-in-queensland-are-getting-bigger-despite-rising-sea-levels-180964">sand budget</a>”. </p>
<p>Recent research has even suggested extreme storms can replenish beaches with <a href="https://theconversation.com/like-20-tip-trucks-pouring-sand-on-every-metre-wide-strip-how-extreme-storms-can-replenish-beaches-not-just-erode-them-182039">more sand from deeper waters</a>. </p>
<p>Under present-day conditions this beach appears to have the capacity to fully recover. This means that it and other similar beaches with positive sand budgets can absorb certain levels of sea-level rise – but only up to a point. There will be a threshold beyond which a beach starts to retreat unless a new source of sand is supplied. </p>
<p>Sources of beach sand could come from deeper water offshore or from neighbouring beaches alongshore. These “credits” of sand into the beach budget may help them maintain their current position. Other NSW beaches in credit include the northern end of Seven Mile Beach near Gerroa, Nine Mile Beach north of Tuncurry and Dark Point just north of Hawks Nest. Around Australia, we can use <a href="https://maps.dea.ga.gov.au/story/DEACoastlines">time-series of shoreline change</a> to estimate beach sand budgets.</p>
<p>Beaches in sand “defecit” are more vulnerable to sea level rise. Examples include the southern end of Stockton Beach and Old Bar in NSW and the northern end of Bribie Island in Queensland. </p>
<p>In a dynamic and volatile future, it is more important than ever that we maintain long-term records of beach change. This will ensure we have a critical baseline of data to test future projections. Monthly surveys at the site are continuing.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-studied-more-than-1-500-coastal-ecosystems-they-will-drown-if-we-let-the-world-warm-above-2-211431">We studied more than 1,500 coastal ecosystems - they will drown if we let the world warm above 2℃</a>
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<img src="https://counter.theconversation.com/content/209213/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Thomas Oliver receives funding from the Australian Research Council and a variety of state and local governments. </span></em></p><p class="fine-print"><em><span>Bruce Thom and Roger McLean do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Storms are the greatest threat to beach erosion, not sea level rise, research reveals. This is the longest continuous beach monitoring survey in the Southern Hemisphere.Thomas Oliver, Senior lecturer, UNSW Canberra, Australian Defence Force AcademyBruce Thom, Emeritus Professor, University of SydneyRoger McLean, Emeritus Professor, UNSW Canberra, Australian Defence Force AcademyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2114312023-08-30T20:36:24Z2023-08-30T20:36:24ZWe studied more than 1,500 coastal ecosystems - they will drown if we let the world warm above 2°C<figure><img src="https://images.theconversation.com/files/545179/original/file-20230829-15-v3if80.jpeg?ixlib=rb-1.1.0&rect=46%2C20%2C3368%2C2826&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Simon Albert</span></span></figcaption></figure><p>Much of the world’s natural coastline is protected by living habitats, most notably mangroves in warmer waters and tidal marshes closer to the poles. These ecosystems support fisheries and wildlife, absorb the impact of crashing waves and clean up pollutants. But these vital services are threatened by global warming and rising sea levels. </p>
<p>Recent research has shown wetlands can respond to sea level rise by building up their root systems, <a href="https://theconversation.com/rising-seas-allow-coastal-wetlands-to-store-more-carbon-113020">pulling carbon dioxide from the atmosphere in the process</a>. Growing recognition of the potential for this “blue” carbon sequestration is driving mangrove and tidal marsh restoration projects. </p>
<p>While the resilience of these ecosystems is impressive, it is not without limits. Defining the upper limits to mangrove and marsh resilience under accelerating sea level rise is a topic of great interest and considerable debate. </p>
<p>Our new research, <a href="https://www.nature.com/articles/s41586-023-06448-z">published today in the journal Nature</a>, analyses the vulnerability and exposure of mangroves, marshes and coral islands to sea level rise. The results underscore the critical importance of keeping global warming within 2 degrees of the pre-industrial baseline. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photo showing uprooted trees in tropical waters of the Solomon Islands." src="https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=215&fit=crop&dpr=1 600w, https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=215&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=215&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=271&fit=crop&dpr=1 754w, https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=271&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/542967/original/file-20230816-19-44orpq.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=271&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Coral islands are contracting, causing habitat loss in the Solomon Islands.</span>
<span class="attribution"><span class="source">Simon Albert</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/not-waving-drowning-why-keeping-warming-under-1-5-is-a-life-or-death-matter-for-tidal-marshes-187540">Not waving, drowning: why keeping warming under 1.5℃ is a life-or-death matter for tidal marshes</a>
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</em>
</p>
<hr>
<h2>What we did</h2>
<p>We pulled together all the available evidence on how mangroves, tidal marshes and coral islands respond to sea level rise. That included: </p>
<ul>
<li><p>delving into the geological record to study how coastal systems responded to past sea level rise, following the last Ice Age</p></li>
<li><p>tapping into a global network of <a href="https://www.usgs.gov/centers/eesc/science/surface-elevation-table">survey benchmarks</a> in mangroves and tidal marshes</p></li>
<li><p>analysing satellite imagery for changes in the extent of wetlands and coral islands at varying rates of sea level rise.</p></li>
</ul>
<p>Altogether, our international team assessed 190 mangroves, 477 tidal marshes and 872 coral reef islands around the world. </p>
<p>We then used computer modelling to work out how much these coastal ecosystems would be exposed to rapid sea level rise under projected warming scenarios. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photo of the eroding wetland at Towra Point in Sydney, showing the stumps and exposed roots of trees washed up on the beach" src="https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545438/original/file-20230830-15-1g4pn5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Eroding wetland at Towra Point in Sydney.</span>
<span class="attribution"><span class="source">Neil Saintilan</span></span>
</figcaption>
</figure>
<h2>What we found</h2>
<p>Mangroves, tidal marshes and coral islands can cope with low rates of sea-level rise. They remain stable and healthy. </p>
<p>We found most tidal marshes and mangroves are keeping pace with current rates of sea level rise, around 2–4mm per year. Coral islands also appear stable under these conditions. </p>
<p>In some locations, land is sinking, so the relative rate of sea level rise is greater. It may be double this 2–4mm figure or more, comparable to rates expected under future climate change. In these situations, we found <a href="https://theconversation.com/not-waving-drowning-why-keeping-warming-under-1-5-is-a-life-or-death-matter-for-tidal-marshes-187540">marshes failing to keep up</a> with sea level rise. They are slowly drowning and in some cases, breaking up. What’s more, these are the same rates of sea level rise under which marshes and mangrove drown in the geological record.</p>
<p>These cases give us a glimpse of the future in a warming world.</p>
<p>So if the rate of sea level rise doubles to 7 or 8 millimetres a year, it becomes “very likely” (90% probability) mangroves and tidal marshes will no longer keep pace, and “likely” (about 67% probability) coral islands will undergo rapid changes. These rates will be reached when the 2.0°C warming threshold is exceeded. </p>
<p>Even at the lower rates of sea level rise we would have between 1.5°C and 2.0°C of warming (4 or 5mm a year), extensive loss of mangrove and tidal marsh is likely. </p>
<p>Tidal marshes are less exposed to these rates of sea level rise than mangroves because they occur in regions where the land is rising, reducing the relative rate of sea level rise.</p>
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<em>
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Read more:
<a href="https://theconversation.com/rising-seas-threaten-to-drown-important-mangrove-forests-unless-we-intervene-49146">Rising seas threaten to drown important mangrove forests, unless we intervene</a>
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<h2>Let’s give coastal ecosystems a fighting chance</h2>
<p>We know mangroves and tidal marshes have survived rapid sea level rise before, at rates even higher than those projected under extreme climate change. </p>
<p>They won’t have long enough to build up root systems or trap sediment in order to stay in place, so they will seek higher ground by shifting landward into newly flooded coastal lowlands. </p>
<p>But this time, they will be competing with other land uses and increasingly trapped behind coastal levees and hard barriers such as roads and buildings. </p>
<p>If the global temperature rise is limited to 2°C, coastal ecosystems have a fighting chance. But if this threshold is exceeded, they will need more help. </p>
<p>Intervention is needed to enable the retreat of mangroves and tidal marshes across our coastal landscapes. There is a role for governments in designating retreat pathways, controlling coastal development, and expanding coastal nature reserves into higher ground. </p>
<p>The future of the world’s living coastlines is in our hands. If we work to restore mangroves and tidal marshes to their former extent, they can help us tackle climate change. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-change-can-drive-social-tipping-points-for-better-or-for-worse-210641">Climate change can drive social tipping points – for better or for worse</a>
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<img src="https://counter.theconversation.com/content/211431/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Neil Saintilan receives funding from the Australian Research Council, the National Environmental Science Program, and the Alexander Von Humboldt Foundation.</span></em></p>Rising seas are pushing coastal ecosystems to the limit of endurance. Now international research reveals a “tipping point” will be reached if we allow more than 2 degrees of global warming.Neil Saintilan, Professor, School of Natural Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2050092023-05-23T12:27:30Z2023-05-23T12:27:30ZMore than two dozen cities and states are suing Big Oil over climate change – they just got a boost from the US Supreme Court<p>Honolulu has lost <a href="https://s3.documentcloud.org/documents/6801979/Honolulu-Climate-Lawsuit-3-9-2020.pdf">more than 5 miles</a> of its famous beaches to sea level rise and storm surges. Sunny-day flooding during high tides makes many city roads impassable, and water mains for the public drinking water system are corroding from saltwater because of sea level rise.</p>
<p>The damage has left the city and county spending millions of dollars on repairs and infrastructure to try to adapt to the rising risks.</p>
<p>Future costs will almost certainly be higher. More than US$19 billion in property value, at today’s dollars, is at risk by 2100 from projected sea level rise, driven by greenhouse gas emissions largely from the burning of fossil fuels. Elsewhere in Honolulu County, which covers all of Oahu, many coastal communities will be cut off or uninhabitable.</p>
<p>Unwilling to have their taxpayers bear the full brunt of these costs, the <a href="https://s3.documentcloud.org/documents/6801979/Honolulu-Climate-Lawsuit-3-9-2020.pdf">city and county sued</a> Sunoco LP, Exxon Mobil Corp. and other big oil companies in 2020.</p>
<p>Their case – one of <a href="https://climateintegrity.org/cases">more than two dozen</a> involving <a href="https://images.theconversation.com/files/527655/original/file-20230523-14019-49gxsv.png">U.S. cities, counties and states suing the oil industry</a> over climate change – just got a break from the U.S. Supreme Court. That has significantly increased their odds of succeeding.</p>
<h2>Suing over the cost of climate change</h2>
<p>At stake in all of these cases is who pays for the staggering cost of a changing climate.</p>
<p>Local and state governments that are suing want to hold the major oil companies responsible for the costs of responding to disasters that scientists are increasingly <a href="https://news.climate.columbia.edu/2021/10/04/attribution-science-linking-climate-change-to-extreme-weather/">able to attribute</a> to climate disruption and <a href="https://doi.org/10.1088/1748-9326/acbce8">tie back to the fossil fuel industry</a>. Several of the plaintiffs accuse the companies of lying to the public about their products’ risks in violation of state or local consumer protection laws that prohibit false advertising.</p>
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<p>The governments in the <a href="https://s3.documentcloud.org/documents/6801979/Honolulu-Climate-Lawsuit-3-9-2020.pdf">Honolulu case allege</a> that the oil companies “are directly responsible” for a substantial rise in carbon dioxide emissions that have been driving climate change. They say the companies should contribute their <a href="https://commonwealthmagazine.org/energy/fair-share-for-the-fossil-fuel-industry/">fair share</a> to defray some of the costs.</p>
<p>The gist of Honolulu’s complaint is that the big oil companies <a href="https://www.science.org/doi/10.1126/science.abk0063">have known for decades</a> that their products cause climate change, yet their public statements continued to <a href="https://theconversation.com/what-big-oil-knew-about-climate-change-in-its-own-words-170642">sow doubts</a> about <a href="https://theconversation.com/i-was-an-exxon-funded-climate-scientist-49855">what was known</a>, and they failed to warn their customers, investors and the public about the dangers posed by their products. </p>
<p>Were it not for this deception, the lawsuit says, the city and county would not be facing mounting costs of abating the damage from climate change.</p>
<p>Importantly, the complaint is based on state – not federal – law. It alleges that the defendants have violated established common law rules long recognized by the courts involving nuisance, failure to warn and trespass.</p>
<p>The city and county want the companies to help fund climate adaptation measures – everything from building seawalls and raising buildings to buying flood-prone properties and restoring beaches and dunes.</p>
<h2>Supreme Court could have killed these cases</h2>
<p>Not surprisingly, the oil companies have thrown their vast legal resources into fighting these cases.</p>
<p>On April 24, however, they lost one of their most powerful arguments.</p>
<p>The U.S. Supreme Court <a href="https://www.supremecourt.gov/orders/courtorders/042423zor_1p24.pdf">declined to hear challenges</a> in the Hawaii case and four others involving the seemingly technical question of which court should hear these cases: state or federal.</p>
<p>The oil companies had “<a href="https://www.bonalaw.com/insights/legal-resources/requirements-for-removing-a-case-from-state-court-to-federal-court">removed</a>” the cases from state court to federal court, <a href="http://climatecasechart.com/case/city-county-of-honolulu-v-sunoco-lp/">arguing that damage lawsuits</a> for climate change go beyond the limits of state law and are governed by federal law. </p>
<p>That theory would have derailed all five cases – because there is no federal common law for greenhouse gases.</p>
<p>The court made that position clear in 2011 in <a href="https://www.oyez.org/cases/2010/10-174">American Electric Power Co. v. Connecticut</a>. Several state and local governments had sued five major power companies for violating the federal common law of interstate nuisance and asked for a court order forcing these companies to reduce their emissions. The Supreme Court refused, holding that the federal Clean Air Act displaced federal common law for these gases. </p>
<p>In <a href="https://law.justia.com/cases/federal/appellate-courts/ca9/09-17490/09-17490-2012-09-21.html">Native Village of Kivalina v. Exxon Mobil Corp.</a>, a federal court of appeals extended that holding to also bar claims for monetary damages based on federal common law.</p>
<figure class="align-center ">
<img alt="Sandbags sit outside a home near a beach in Oahu, Hawaii, where waves have eaten into the shoreline almost up to the house." src="https://images.theconversation.com/files/527383/original/file-20230521-128284-x96kaz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/527383/original/file-20230521-128284-x96kaz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/527383/original/file-20230521-128284-x96kaz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/527383/original/file-20230521-128284-x96kaz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/527383/original/file-20230521-128284-x96kaz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/527383/original/file-20230521-128284-x96kaz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/527383/original/file-20230521-128284-x96kaz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Several coastal communities, including in Honolulu County, facing increasing erosion want oil companies to help pay for protective infrastructure.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/4c2fc5b90f894fe7963daeb19724bce4?ext=true">AP Photo/Audrey McAvoy</a></span>
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<p>To avoid this fate, Honolulu and the other plaintiffs focused on violations of state law, not federal law. Without exception, the federal courts of appeals sided with them and sent the cases back to state court.</p>
<h2>What happens next?</h2>
<p>The Honolulu case leads the pack at this point.</p>
<p>In 2022, the 1st Circuit Court in Hawaii <a href="http://climatecasechart.com/climate-change-litigation/wp-content/uploads/sites/16/case-documents/2022/20220203_docket-1CCV-20-0000380_ruling.pdf">denied the oil companies’ motion</a> to dismiss the case based on the argument that the Clean Air Act also preempts state common law. This could open the door for discovery to begin sometime this year.</p>
<p>In discovery, senior corporate officers – perhaps including <a href="https://theconversation.com/exxons-rex-tillerson-and-the-rise-of-big-oil-in-american-politics-70260">former Exxon Mobil CEO Rex Tillerson</a>, who was secretary of state under Donald Trump – will be required to answer questions under oath about what the companies knew about climate change versus what they disclosed to the public.</p>
<figure class="align-center ">
<img alt="Rex Tillerson, a smiling older man in a suit and tie, walks out of a courthouse with security guards." src="https://images.theconversation.com/files/527353/original/file-20230521-106641-dkrcqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/527353/original/file-20230521-106641-dkrcqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/527353/original/file-20230521-106641-dkrcqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/527353/original/file-20230521-106641-dkrcqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/527353/original/file-20230521-106641-dkrcqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/527353/original/file-20230521-106641-dkrcqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/527353/original/file-20230521-106641-dkrcqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">In 2019, former Exxon Mobil CEO Rex Tillerson testified in a securities fraud lawsuit brought by the New York attorney general’s office. The judge ruled in Exxon’s favor.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/ExxonClimateLawsuit/cc7e743167614cb4bf7a4ec99319422f/photo">AP Photo/Seth Wenig</a></span>
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<p>Evidence <a href="https://www.science.org/doi/10.1126/science.abk0063">from Exxon documents</a>, described in a recent study by science historians Naomi Oreskes and Geoffrey Supran, shows that the company’s own scientists “knew as much as academic and government scientists knew” about climate change going back decades. But instead of communicating what they knew, “Exxon worked to deny it,” Supran and Oreskes write. The company overemphasized uncertainties and cast doubt on climate models.</p>
<p>This is the kind of evidence that could sway a jury. The standard of proof in a civil case like Honolulu’s is “preponderance of the evidence,” which roughly translates to 51%. Ten of the 12 jurors must agree on a verdict.</p>
<p>Any verdict likely would be appealed, perhaps all the way to the U.S. Supreme Court, and it could be years before the Honolulu case is resolved.</p>
<h2>Lawsuits don’t begin to cover the damage</h2>
<p>It is unlikely that even substantial verdicts in these cases will come close to covering the full costs of damage from climate change.</p>
<p>According to the National Oceanic and Atmospheric Administration, <a href="https://www.climate.gov/news-features/blogs/2022-us-billion-dollar-weather-and-climate-disasters-historical-context">in 2022 alone the U.S. sustained</a> 18 weather and climate disasters that each exceeded $1 billion in damage. Together, they cost over $165 billion.</p>
<p>But for many of the communities most at risk from these disasters, every penny counts. We believe establishing the oil companies’ responsibility may also discourage further investments in fossil fuel production by banks and brokerage houses already nervous about the <a href="https://www.ey.com/en_it/banking-capital-markets-risk-regulatory-transformation/climate-change-and-risk-three-key-challenges-facing-banks">financial risks</a> of climate disruption.</p><img src="https://counter.theconversation.com/content/205009/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Honolulu, Baltimore, Charleston, S.C. and several other cities harmed by rising seas and extreme weather are suing the oil industry. At stake is who pays for the staggering costs of climate change.Patrick Parenteau, Professor of Law Emeritus, Vermont Law & Graduate SchoolJohn Dernbach, Professor of Law, Widener UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2028912023-04-21T09:06:05Z2023-04-21T09:06:05ZShakespeare’s environmentalism: how his plays explore the same ecological issues we face today<p>Climate change, urban sprawl, air pollution, deforestation, depleted fish stocks, biodiversity and species loss: these are not exclusively modern problems that only sprang up in the last few hundred years. In fact, the common but misleading phrase “industrial revolution” masks the <a href="https://nora.nerc.ac.uk/id/eprint/507339/1/A%20once%20and%20future%20extractive%20history%20of%20Britain.pdf">long history of resource extraction</a> and ecological degradation in the British Isles stretching back at least to the arrival of the <a href="https://www.roman-britain.co.uk/life-in-roman-britain/mining-in-roman-britain/">tin-hungry Romans</a>. </p>
<p><a href="https://www.bl.uk/shakespeare/articles/key-features-of-renaissance-culture">Renaissance England</a> was reeling from the effects of all these problems. Often hailed as the <a href="https://www.britannica.com/art/English-literature/Elizabethan-and-early-Stuart-drama">golden age of English literature</a>, the Renaissance was also the apex of the “<a href="https://theconversation.com/the-original-climate-crisis-how-the-little-ice-age-devastated-early-modern-europe-178187">little ice age</a>”, in which a cooler climate produced poorer harvests.</p>
<p>These food shortages were especially difficult because England’s <a href="https://www.gale.com/intl/essays/matthew-clark-tudor-society">human population surged</a> fourfold in the 16th century, while the <a href="https://tudorhistory.org/glossaries/e/enclosure.html">enclosure of common lands</a> forced more country-dwellers to flock to London. Given how heavily these environmental concerns weighed on a society coping with chronic scarcity, it should come as no surprise that we can find traces of them in the works of England’s greatest playwright.</p>
<h2>King and countryside</h2>
<p>When <a href="https://www.royal.uk/james-i">King James</a> became his patron in 1603, Shakespeare was tasked with writing plays to entertain a keen outdoorsman and hunter who was as much preoccupied with the material state of the British countryside as with matters of state. No wonder, then, the Shakespearean stage encompasses a remarkable variety of landscapes and features an abundance of animal imagery to rival the <a href="https://www.hrp.org.uk/tower-of-london/history-and-stories/the-tower-of-london-menagerie/#gs.ujqfoc">royal menagerie</a> – basically King James’s private zoo – and compensate for England’s dwindling numbers of wild game.</p>
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<img alt="" src="https://images.theconversation.com/files/520292/original/file-20230411-22-7ego8p.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/520292/original/file-20230411-22-7ego8p.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520292/original/file-20230411-22-7ego8p.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520292/original/file-20230411-22-7ego8p.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520292/original/file-20230411-22-7ego8p.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520292/original/file-20230411-22-7ego8p.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520292/original/file-20230411-22-7ego8p.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em>This article is part of our <a href="https://theconversation.com/uk/topics/william-shakespeare-14574">First Folio 400</a> series. These articles mark the 400th anniversary of the publication of the First Folio, the first collected edition of William Shakespeare’s plays.</em></p>
<hr>
<p>It would, of course, be an anachronism to dub Shakespeare an environmentalist. But he was acutely aware of what we would term the environmental issues of his era. In particular, the plays Shakespeare composed during the reign of James frequently intervene in environmental policy disputes at the Stuart court about how best to carve up the natural riches of the realm.</p>
<p><a href="https://www.bl.uk/works/macbeth">Macbeth’s</a> famous depiction of the “blasted heath” reflects the increasingly negative views of this terrain as a sterile abode of witches and <a href="https://www.ourmigrationstory.org.uk/oms/romani-gypsies-in-16th-century-britain">Romani</a> people that should be transformed into private farmland.</p>
<p>Although James dreaded witches, he and parliament sought to protect heathland as a habitat for game animals and birds. He would have relished Shakespeare’s comparing Macbeth to a poacher and a <a href="https://www.rspb.org.uk/our-work/conservation/conservation-and-sustainability/safeguarding-species/case-studies/red-kite/">kite</a>, a species then classified as vermin. Macbeth’s killing of Duncan and Macduff’s (pronounced Macdove) family simulates illegal net-hunting, nest-robbing, and the raiding of estate buildings known as <a href="https://www.nationaltrust.org.uk/discover/history/architecture/what-is-a-dovecote">dovecotes</a>, which housed pigeons and doves for food and feathers. </p>
<h2>Enduring environmental issues</h2>
<p>In <a href="https://www.rsc.org.uk/pericles/the-plot">Pericles</a>, Shakespeare wades into pan-European squabbles about fishing rights amid a crash in North Sea fishing stocks. Its conclusion mirrors James’ plan to end the <a href="https://www.deruyter.org/uploads/media/5acf9125b45c4.pdf">herring wars</a> (the ongoing feud between England and its coastal neighbours over territorial control of fishing areas) by forging dynastic alliances through the marriage of his heirs.</p>
<p>Interestingly, Pericles also plays on fears of coastal erosion. Shakespeare adapted the story from a writer whose father had proposed the existence of a flooded land-bridge linking Britain to the continent (now known as <a href="https://education.nationalgeographic.org/resource/doggerland/">Doggerland</a>.</p>
<p>While the shipwrecked king refutes claims to rule the unruly seas, the costumes donned by Shakespeare’s actors would have told a different story. Pericles and his family almost certainly appeared in robes of <a href="https://www.bbc.com/culture/article/20180801-tyrian-purple-the-regal-colour-taken-from-mollusc-mucus">Tyrian purple</a>. This dye, made in Pericles’ home town from crushed sea snails, could only be worn by royalty and would thus have been a striking visual symbol of royal dominion over the ocean. </p>
<p><a href="https://www.rsc.org.uk/the-winters-tale">The Winter’s Tale</a> comments on the inhumanity of the fur trade. The famous bear that pursues Antigonus off stage may have been played by an actor in a polar bear’s pelt captured by fur traders, while Queen Hermione is a personification of an <a href="https://ztevetevans.wordpress.com/2016/04/18/stoats-in-folklore-and-heraldry/">ermine</a>.</p>
<p>Spelled “ermion” in Shakespeare’s day, an ermine is a stoat in its white winter coat. Ermines were symbols of chastity since it was believed they would rather die than befoul their white fur. </p>
<p>Hermione acts like her namesake when she exclaims she too would rather die than stain her name as an adulteress. The trial scene in which she would be stripped of her white fur re-enacts the flaying of an animal, while the scene in which her statue is reanimated captures a fascination with the new, death-defying art of taxidermy. </p>
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<p><a href="https://www.shakespeare.org.uk/explore-shakespeare/shakespedia/shakespeares-plays/king-lear/">King Lear</a> proclaims humans no better than beasts and is a tour de force demonstration of our vulnerability to both extreme weather and darkness. In <a href="https://www.shakespeare.org.uk/explore-shakespeare/shakespedia/shakespeares-plays/cymbeline">Cymbeline</a>, Shakespeare expresses a newfound appreciation for mountain wilderness as a preserve not only of game animals but also of Britishness and masculinity.</p>
<p>Few people realise <a href="https://www.shakespeare.org.uk/explore-shakespeare/shakespedia/shakespeares-plays/tempest/">The Tempest</a> is based on legends of a demon-battling hermit from the English fens. Its notorious monster Caliban voices the outrage of fenland communities dispossessed by schemes to drain and enclose their wetlands.</p>
<p><a href="https://www.shakespeare.org.uk/explore-shakespeare/shakespedia/shakespeares-plays/measure-measure/">Measure For Measure</a> reveals how <a href="https://www.britannica.com/science/plague/History">the plague</a> stoked fears of urban overpopulation, while <a href="https://www.shakespeare.org.uk/explore-shakespeare/shakespedia/shakespeares-plays/timon-athens/">Timon of Athens</a> offer’s a scathing satire on the mining lobby and its cornucopian economics: the notion that the earth’s wealth is inexhaustible. </p>
<p>In inserting these environmental issues into his plays, Shakespeare forced his audience to reflect on the political, moral, and spiritual implications of early modern England’s growing power to transform the natural world. His fascination with kings might seem old-fashioned, but in our brave new era of the <a href="https://www.nhm.ac.uk/discover/what-is-the-anthropocene.html">Anthropocene</a>, in which our species has become the dominant geological force, we can better appreciate how he often uses kingship as a metaphor for human tyranny over nature. </p>
<p>Shakespeare’s profound sympathies for the disempowered outsider also extend to non-human creatures. When his high and mighty despots have their comeuppance out in the wilds, learning that the earth doesn’t exist to bend to them, Shakespeare’s plays are teaching us all to relinquish the delusion that we are entitled to dominate the planet.</p><img src="https://counter.theconversation.com/content/202891/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Todd Andrew Borlik does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Worrying environmental issues dominated the time of William Shakespeare as they do now, from depleted fish stocks and food shortages, to overpopulation and animal exploitation.Todd Andrew Borlik, Reader in Renaissance Drama, University of HuddersfieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1985052023-02-09T19:11:53Z2023-02-09T19:11:53ZMillions of satellite images reveal how beaches around the Pacific vanish or replenish in El Niño and La Niña years<p>If you’ve been visiting the same beach for a few summers, you’ll have seen it change. While beaches look static, they’re actually one of the most dynamic regions on Earth. Winds, waves and tides stir and push sand around constantly. Storms can claw out huge volumes of sand and move it elsewhere. </p>
<p>On top of these changes is a hidden force – the El Niño Southern-Oscillation (ENSO) climate cycle. Our <a href="https://www.nature.com/articles/s41561-022-01117-8">new research</a> explores how this cycle affects beaches around the Pacific Rim. Using cutting-edge satellite technology, we tracked changes over 40 years. </p>
<p>What did we find? The cycle matters a great deal. While the natural ENSO Pacific climate phenomenon affects weather patterns around the world, we haven’t fully understood how it affects beaches. </p>
<p>The main impact? Coastal storms intensified by the ENSO cycle. Storms can rapidly strip sand from beaches to create sandbars, dump it out at sea, or replenish another beach. These changes threaten to undermine beachfront properties and roads as well as beach habitats. </p>
<p>For Australia, if a La Niña is predicted to arrive in the next six months, coastal communities prone to erosion should prepare for storms stripping away sand. Our recent repeat La Niñas brought large waves and heavy erosion along the New South Wales and southern Queensland coast. During this period, houses <a href="https://www.theguardian.com/australia-news/2020/jul/18/nsw-central-coast-houses-partially-collapse-after-beach-erosion-caused-by-swells">almost fell</a> into the sea in the NSW Central Coast, while wild waves made a <a href="https://www.sunshinecoastnews.com.au/2023/02/05/in-photos-how-passage-has-changed-in-one-year/">new passage</a> through Bribie Island. </p>
<p>During El Niño, Australia’s beaches recover, while beaches from California to Chile erode. </p>
<p>But as climate change ramps up, the effects of these ENSO cycles may become <a href="https://www.nature.com/articles/s43017-021-00199-z">more intense</a>.</p>
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<img alt="" src="https://images.theconversation.com/files/506712/original/file-20230127-24-5hynl.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506712/original/file-20230127-24-5hynl.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506712/original/file-20230127-24-5hynl.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506712/original/file-20230127-24-5hynl.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506712/original/file-20230127-24-5hynl.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506712/original/file-20230127-24-5hynl.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506712/original/file-20230127-24-5hynl.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Extreme beach erosion during a coastal storm in 2020 at Wamberal, Central Coast, NSW.</span>
<span class="attribution"><span class="source">Christopher Drummond/UNSW Water Research Laboratory.</span></span>
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<h2>What did we find?</h2>
<p>We analysed millions of satellite images, looking for changes in beach width during El Niño and La Niña periods in southeast Australia, New Zealand, Chile, Peru, Mexico, California and Japan. </p>
<p>Lying in the satellite data was clear evidence of cyclical change. Along southeast Australia’s coastline, beaches tended to erode during prolonged La Niña periods, while regaining sand and recovering during El Niño years. </p>
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Read more:
<a href="https://theconversation.com/the-wild-weather-of-la-nina-could-wipe-out-vast-stretches-of-australias-beaches-and-sand-dunes-191941">The wild weather of La Niña could wipe out vast stretches of Australia's beaches and sand dunes</a>
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<p>The reverse was true on the other side of the Pacific, around 13,000 kilometres away. From California down through Mexico to Chile and Peru, we saw beaches narrow during El Niño periods and widen out again during La Niña periods. </p>
<p>Why? Storms and sea levels. During El Niño events, large storms develop in the northern Pacific, sending energetic waves crashing onto the coastlines of California and Mexico — creating the perfect conditions for big wave surfing. During this period, the sea level is well above average too. Combined, bigger waves, storms and a higher baseline pillage sandy beaches. This is particularly pronounced in the eastern Pacific. </p>
<p>Knowing this, we can be better prepared. If you’re in Australia and the <a href="http://www.bom.gov.au/climate/enso/outlook/">ENSO outlook</a> suggests a La Niña is coming, it might be time for councils to replenish erosion prone beaches. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=198&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=198&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=198&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=249&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=249&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507768/original/file-20230202-4615-1iaiaf.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=249&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">ENSO outlook for February 2023.</span>
<span class="attribution"><span class="source">Australian Bureau of Meteorology</span></span>
</figcaption>
</figure>
<h2>Monitoring the many moods of a beach</h2>
<p>Monitoring coastal change has long been carried out with on-ground techniques, such as GPS equipment, quadbikes and drones. These methods require human operators, which makes them expensive and limits the area and duration of observations. That’s why we have very limited on-ground observations of beach change along much of the world’s coastline.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/506722/original/file-20230127-14-x05xf1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506722/original/file-20230127-14-x05xf1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506722/original/file-20230127-14-x05xf1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506722/original/file-20230127-14-x05xf1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506722/original/file-20230127-14-x05xf1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506722/original/file-20230127-14-x05xf1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506722/original/file-20230127-14-x05xf1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">On-ground survey techniques to monitor beaches.</span>
<span class="attribution"><span class="source">Larry Paice/UNSW Water Research Laboratory.</span></span>
</figcaption>
</figure>
<p>That’s where satellites can help. Earth observation satellites have been capturing regular images of the world’s coastlines for four decades. Now we have the tools to interrogate the satellite images and track the evolution of sandy beaches.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australia-relies-on-data-from-earth-observation-satellites-but-our-access-is-high-risk-82985">Australia relies on data from Earth observation satellites, but our access is high risk</a>
</strong>
</em>
</p>
<hr>
<p>We developed the open-source tool <a href="https://github.com/kvos/CoastSat">CoastSat</a> to automatically map the position of the shoreline on freely available satellite images, using cutting-edge image processing and machine learning techniques.</p>
<figure class="align-center ">
<img alt="CoastSat toolbox" src="https://images.theconversation.com/files/507753/original/file-20230202-19-6lbgd6.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507753/original/file-20230202-19-6lbgd6.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=522&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507753/original/file-20230202-19-6lbgd6.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=522&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507753/original/file-20230202-19-6lbgd6.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=522&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507753/original/file-20230202-19-6lbgd6.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=656&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507753/original/file-20230202-19-6lbgd6.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=656&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507753/original/file-20230202-19-6lbgd6.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=656&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Changes to the shoreline can be automatically detected, as in this animation of changes at Narrabeen-Collaroy beach, Sydney.</span>
<span class="attribution"><span class="source">Killian Vos</span></span>
</figcaption>
</figure>
<p>With tools like these, we can monitor coastal changes across thousands of beaches over the last 40 years. You can see how your local beach has changed on the interactive <a href="http://coastsat.wrl.unsw.edu.au/">CoastSat website</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-wild-weather-of-la-nina-could-wipe-out-vast-stretches-of-australias-beaches-and-sand-dunes-191941">The wild weather of La Niña could wipe out vast stretches of Australia's beaches and sand dunes</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/198505/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kilian Vos receives funding from the United States Geological Survey (USGS). </span></em></p><p class="fine-print"><em><span>Mitchell Harley receives funding from the Australian Research Council. He is the NSW Chair of the Australian Coastal Society</span></em></p>We can now monitor coastal changes across thousands of beaches over the last 40 years, from Australia, New Zealand and Japan, to Chile, Peru, Mexico and California. Here’s what our new tool uncovered.Kilian Vos, Research Associate, UNSW SydneyMitchell Harley, Scientia Senior Lecturer, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1953572022-11-30T00:40:01Z2022-11-30T00:40:01ZCoastal property prices and climate risks are both soaring. We must pull our heads out of the sand<p>Australians’ <a href="https://www.nfsa.gov.au/collection/curated/australians-beach">well-documented</a> affinity with the sun, surf and sand continues to fuel <a href="https://www.smh.com.au/property/news/stunning-holiday-hotspots-where-house-prices-have-doubled-in-five-years-20221109-p5bwuk.html">coastal property market growth</a>. This growth defies rising interest rates and growing evidence of the <a href="https://www.theguardian.com/australia-news/2020/jul/23/against-the-tide-storm-battered-wamberal-residents-cling-to-beachfront-homes">impacts of climate change</a> on people living in vulnerable coastal locations. </p>
<p>People in these areas are finding it harder to insure their properties against these risks. Insurers view the Australian market as sensitive to climate risks, as climate change impacts can trigger large insurance payouts. They are <a href="https://www.theguardian.com/australia-news/2022/nov/12/australians-facing-prohibitive-insurance-premiums-after-climate-related-disasters">pricing their products accordingly</a>. </p>
<p>Clearly, there is a vast disconnect between the coastal property market and climate change impacts such as increasingly severe storms, tidal surges, coastal erosion and flooding. There is no shortage of <a href="https://www.smh.com.au/business/banking-and-finance/32-billion-of-cba-mortgages-exposed-to-extreme-weather-risks-climate-analysis-finds-20220819-p5bb5p.html">reports</a>, <a href="https://www.climatecouncil.org.au/resources/australian-homes-uninsurable-2030-climate-risk-map/">studies</a> and <a href="https://www.abc.net.au/news/2022-11-18/gold-coast-council-additional-88-000-properties-at-flood-risk/101664596">analyses</a> confirming the climate risks we are already living with. Yet another alarming <a href="https://www.csiro.au/en/research/environmental-impacts/climate-change/State-of-the-Climate">State of the Climate</a> report was released last week.</p>
<p>We keep talking about reaching global net-zero emissions. But this “<a href="https://www.youtube.com/watch?v=ZwD1kG4PI0w">blah blah blah</a>” masks the fact that climate impacts are already with us. Even if we make deeper, faster cuts to emissions, as we must, our world is now warmer. Australians will <a href="https://www.science.org.au/supporting-science/science-policy-and-analysis/reports-and-publications/risks-australia-three-degrees-c-warmer-world">feel the effects of that warming</a>. </p>
<p>We ultimately cannot afford the price of business as usual, as embodied by so many coastal developments. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/ZwD1kG4PI0w?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Greta Thunberg denounces the ‘blah, blah, blah’ from world leaders in response to the climate emergency.</span></figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/state-of-the-climate-what-australians-need-to-know-about-major-new-report-195136">State of the climate: what Australians need to know about major new report</a>
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</em>
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<hr>
<h2>Risks are worrying banks and insurers</h2>
<p>In Australia, the disasters and the environmental collapse we are experiencing will get worse. While a range of businesses see this as opening up <a href="https://www.accc.gov.au/media-release/accc-internet-sweeps-target-greenwashing-fake-online-reviews">new market and product frontiers</a>, the fact is climate change is creating a fundamentally uncertain, unstable and difficult world. </p>
<p>Banks have a <a href="https://law-store.wolterskluwer.com/s/product/banking-on-climate-change-how-finance-actors-regulatory-regimes/01t0f00000J3aMk">central role</a> in addressing climate risks. They are <a href="https://theconversation.com/how-can-your-bank-help-reduce-climate-change-risks-to-your-home-60049">exposed to climate risk</a> through residential lending on properties that are vulnerable to climate impacts and now <a href="https://www.theguardian.com/australia-news/2022/nov/26/australias-unraveling-climate-risk-leaving-more-homes-uninsurable-against-flooding-expert-warns">face insurance pressures</a>. </p>
<p>One in 25 Australian homes are <a href="https://www.climatecouncil.org.au/resources/australian-homes-uninsurable-2030-climate-risk-map/">projected to be uninsurable by 2030</a>. The Australian government risks bearing the large costs of supporting the underinsured or uninsured – otherwise known as <a href="https://www.pc.gov.au/inquiries/completed/disaster-funding/report">being “the insurer of last resort”</a>.</p>
<p>This costly legacy shows why planning decisions made now must take account of climate change impacts, and <a href="https://link.springer.com/article/10.1007/s40641-020-00161-z">not just in the wake of disasters</a>.</p>
<p>The rapidly escalating impacts and risks across sectors demand that we undertake mitigation and adaptation at the same time, urgently and on a large scale. This means reducing emissions to negative levels – not just reaching net zero and transitioning our energy sector, but also actively removing greenhouse gases from the atmosphere. </p>
<p>We must also respond to climate change risks already locked into the system. We have to make substantial changes in how we think about, treat, price and act on these risks. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1596294943529893888"}"></div></p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-insurers-can-get-better-at-responding-to-natural-disasters-75846">How insurers can get better at responding to natural disasters</a>
</strong>
</em>
</p>
<hr>
<h2>As the climate shifts, so must our coastal dream</h2>
<p>The consequences of a warming climate, including reaching and crossing tipping points in the Earth’s weather systems, are <a href="https://www.science.org/doi/10.1126/science.abn7950#core-collateral-purchase-access">occurring sooner than anticipated</a>. The required behavioural, institutional and structural changes are vast and challenging. </p>
<p>People are often attached to places based on <a href="https://rgs-ibg.onlinelibrary.wiley.com/doi/abs/10.1111/tran.12368">historical knowledge</a> of them. These lived experiences, while important, inform a worldview based on an understanding of our environment before the <a href="https://link.springer.com/chapter/10.1007/978-981-19-2428-6_2">rapid onset</a> of climate change. This can skew our climate risk responses, but compounding climate impacts are outpacing our ability to adapt as we might have in the past. </p>
<p>Institutional signalling, such as <a href="https://www.smh.com.au/business/the-economy/property-values-are-at-risk-in-climate-change-hot-spots-rba-warns-20210917-p58skt.html">warnings by the Reserve Bank</a>, support greater public awareness of climate impacts and risks. </p>
<p>When buying a property, people need to consider these factors more seriously than, say, having an extra bathroom. Obligatory disclosure of regional climate change impacts could inform buyers’ decision-making. The data and models used would have to be clear on the validity and limitations of their scenarios. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1420173588217303044"}"></div></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/building-too-close-to-the-water-its-ridiculous-talk-of-buyouts-after-floods-shows-need-to-get-serious-about-climate-adaptation-186999">'Building too close to the water. It's ridiculous!' Talk of buyouts after floods shows need to get serious about climate adaptation</a>
</strong>
</em>
</p>
<hr>
<h2>Nature-based and equitable solutions</h2>
<p>In recent years there has been an increasing focus on nature-based solutions. This approach uses natural systems and tools for tackling societal issues such as the enormous and complex risks posed by climate change. Indeed, many Indigenous peoples, communities and ways of knowing <a href="https://www.facetsjournal.com/doi/full/10.1139/facets-2019-0058">have long recognised</a> the fundamental role of nature in making good and safe lives possible for people. </p>
<p>Nature-based solutions provide a suite of valuable tools for remedying issues we’re already facing on coasts. <a href="https://www.sciencedirect.com/science/article/abs/pii/S0964569121000399">For example</a>, in many contexts, building hard seawalls is often a temporary solution, which instils a false sense of security. Planting soft barriers such as mangroves and dense, deep-rooting vegetation can provide a more enduring solution. It also restores fish habitat, purifies water and eases floods.</p>
<p>Acknowledging the well-being of people and nature as interconnected has important implications for decisions about relocating people from high-risk areas. Effective planned retreat strategies must not only get people out of harm’s way, but account for where they will move and how precious ecosystems will be protected as demand for land supply shifts. Nature-based solutions must be built into retreat policies too. </p>
<p>As the Australian Academy of Science’s <a href="https://www.science.org.au/news-and-events/events/launch-national-strategy-just-adaptation">Strategy for Just Adaptation</a> explains, effective adaptation also embeds equity and justice in the process. <a href="https://link.springer.com/article/10.1007/s10584-019-02535-1">Research</a> on historic retreat strategies has shown that a failure to properly consider and respect people’s choices, resources and histories can further entrench inequities. Giving people moving to a new home as much choice as possible helps them work through an emotional and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0964569116301119">highly political process</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/after-the-floods-the-distressing-but-necessary-case-for-managed-retreat-178641">After the floods, the distressing but necessary case for managed retreat</a>
</strong>
</em>
</p>
<hr>
<p>We all need to find the courage to have difficult conversations, to seek information to make prudent choices, and to do all we can to respond to the growing climate risks that confront us. As climate activist Greta Thunburg <a href="https://www.youtube.com/watch?v=ZwD1kG4PI0w">says</a>: </p>
<blockquote>
<p>“Hope is not passive. Hope is not blah blah blah. Hope is telling the truth. Hope is taking action. And hope always comes from the people.” </p>
</blockquote>
<p>Acting on this kind of hope can put us on an altogether different and more positive path.</p><img src="https://counter.theconversation.com/content/195357/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tayanah O'Donnell has previously received research funding from AMP Foundation, the BHP Foundation, the Lord Mayor's Charitable Trust, the Institute of Australian Geographers, Western Sydney University, the University of Canberra, and state and federal governments. These grants supported over 13 years of research in climate change adaptation and in sustainable development, including managed retreat, climate policy, and climate risk duties and disclosures. She is a Deloitte Australia Climate and Sustainability Partner where she leads the Canberra climate practice. She is also an honorary Associate Professor at the Australian National University. </span></em></p><p class="fine-print"><em><span>Eleanor Robson is a PhD student at Western Sydney University and a Manager in Deloitte's Risk Advisory practice. Eleanor has formerly worked for a parliamentarian in the Australian Labor Party. </span></em></p>Booming prices for coastal properties are a mark of our reluctance to reckon with the climate change that is already upon us. We must start to properly account for and act on climate risk.Tayanah O'Donnell, Honorary Associate Professor, Australian National UniversityEleanor Robson, PhD Candidate, Institute for Culture and Society, Western Sydney UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1944922022-11-23T13:18:18Z2022-11-23T13:18:18ZDreaming of beachfront real estate? Much of Florida’s coast is at risk of storm erosion that can cause homes to collapse, as Daytona just saw<figure><img src="https://images.theconversation.com/files/496325/original/file-20221120-14-dqpu65.jpg?ixlib=rb-1.1.0&rect=0%2C13%2C3000%2C1980&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dozens of homes were left unstable in the Daytona Beach area after Hurricane Nicole's erosion.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/people-look-on-at-homes-that-are-partially-toppled-onto-the-news-photo/1440607558">Joe Raedle/Getty Images</a></span></figcaption></figure><p>Back-to-back hurricanes left an unnerving scene on the Florida coast in November 2022: Several houses, and even swimming pools, were left dangling over the ocean as waves eroded the property beneath them. <a href="https://www.facebook.com/VolusiaCountyEmergencyManagement/posts/pfbid02EZ9SbTjdQhrkGtFm452UhzhzjprPu6h6WaQbPLuMLsRNpCLAuPoPKTZDUvjygUb7l">Dozens of homes and condo buildings</a> in the Daytona Beach area were deemed unsafe. </p>
<p>The destruction has raised a disturbing question: How much property along the rest of the Florida coast is at risk of collapse, and can it be saved?</p>
<p>As the director of <a href="https://dcp.ufl.edu/iadapt/">iAdapt</a>, the International Center for Adaptation Planning and Design at the University of Florida, <a href="https://scholar.google.com/citations?user=ngiXpvgAAAAJ&hl=en">I have been</a> studying climate adaptation issues for the last two decades to help answer these questions.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/h6Fvx6Cw4tE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Drone footage shows homes close to collapsing into the ocean. WPLG/YouTube.</span></figcaption>
</figure>
<h2>Rising seas, aging buildings</h2>
<p>Living by the sea has a strong appeal in Florida – beautiful beaches, ocean views, and often pleasant breezes. However, there are also risks, and they are exacerbated by climate change.</p>
<p>Sea level is forecast to rise on average <a href="https://oceanservice.noaa.gov/hazards/sealevelrise/sealevelrise-tech-report.html">10 to 14 inches</a> (25-35 cm) on the U.S. East Coast over the next 30 years, and 14 to 18 inches (35-45 cm) on the Gulf Coast, <a href="https://theconversation.com/ipcc-climate-report-profound-changes-are-underway-in-earths-oceans-and-ice-a-lead-author-explains-what-the-warnings-mean-165588">as the planet warms</a>. Rising temperatures are also <a href="https://climate.nasa.gov/news/3184/a-force-of-nature-hurricanes-in-a-changing-climate/">increasing the intensity</a> of hurricanes.</p>
<p>With higher seas and larger storm surges, ocean waves more easily erode beaches, weaken sea walls, and submerge cement foundations in corrosive salt water. Together with <a href="https://geodata.dep.state.fl.us/datasets/194ac159bd1e4be294b14dd882d42dcf_0/about">subsidence</a>, or sinking land, they make coastal living riskier.</p>
<figure class="align-center ">
<img alt="Map showing red lines along most of Florida's coast, except at wetlands areas and at the bend toward the Panhandle." src="https://images.theconversation.com/files/496253/original/file-20221119-9310-8cyf0g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/496253/original/file-20221119-9310-8cyf0g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=575&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496253/original/file-20221119-9310-8cyf0g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=575&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496253/original/file-20221119-9310-8cyf0g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=575&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496253/original/file-20221119-9310-8cyf0g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=722&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496253/original/file-20221119-9310-8cyf0g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=722&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496253/original/file-20221119-9310-8cyf0g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=722&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Florida’s erosion risk map shows most of the state’s coastline at critical risk.</span>
<span class="attribution"><a class="source" href="https://geodata.dep.state.fl.us/datasets/FDEP::coastal-critical-erosion-areas/about">Florida Department of Environmental Protection</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The risk of erosion varies depending on the soil, geology and natural shoreline changes. But it is widespread in U.S. coastal areas, <a href="https://geodata.dep.state.fl.us/datasets/FDEP::coastal-critical-erosion-areas/about">particularly Florida</a>. Maps produced by engineers at the <a href="https://geodata.dep.state.fl.us/datasets/FDEP::coastal-critical-erosion-areas/about">Florida Department of Environmental Protection</a> show most of Florida’s coast faces critical erosion risk.</p>
<p>Aging or poorly maintained buildings and sea walls, and older or poor construction methods and materials, can dramatically <a href="https://www.nationalgeographic.com/environment/article/sinking-land-rising-seas-dual-crises-facing-coastal-communities">aggravate the risk</a>.</p>
<h2>Designing better building codes</h2>
<p>So, what can be done to minimize the damage?</p>
<p>The first step is to build sturdier buildings and fortify existing ones according to advanced building codes.</p>
<p>Building codes change over time as risks rise and construction techniques and materials improve. For example, design criteria in the <a href="https://codes.iccsafe.org/content/FLBC2020P1">Florida Building Code</a> for South Florida changed from requiring some new buildings to be able to withstand 146 mph sustained winds in 2002 to 195 mph winds in 2021, meaning a powerful Category 5 hurricane.</p>
<p>The town of <a href="https://www.washingtonpost.com/climate-solutions/2022/10/01/punta-gorda-hurricane-ian-damage/">Punta Gorda</a>, near where Hurricane Ian made landfall in October 2022, showed how homes constructed to the latest building codes have a much better chance of survival.</p>
<p>Many of Punta Gorda’s buildings had been rebuilt after Hurricane Charley in 2004, shortly after the state updated the Florida Building Code. When Ian hit, they survived with less damage than those in neighboring towns. The updated code required new construction to be able to withstand hurricane-force winds, including having shutters or impact-resistant window glass.</p>
<figure class="align-center ">
<img alt="A man clears palm branches from a yard with fallen palm trees in the background, but house standing with no visible damage." src="https://images.theconversation.com/files/496870/original/file-20221122-21-motmg7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/496870/original/file-20221122-21-motmg7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496870/original/file-20221122-21-motmg7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496870/original/file-20221122-21-motmg7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496870/original/file-20221122-21-motmg7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496870/original/file-20221122-21-motmg7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496870/original/file-20221122-21-motmg7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Many homes in Punta Gorda fared better in Hurricane Ian’s winds because they had been rebuilt to higher standards after Hurricane Charley in 2002.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/man-cleans-up-debris-in-the-aftermath-of-hurricane-ian-in-news-photo/1243602882?phrase=punta%20gorda&adppopup=true">Bryan R. Smith / AFP</a></span>
</figcaption>
</figure>
<p>However, even homes built to the latest codes can be vulnerable, because the codes don’t adequately address the environment that buildings sit on. A modern building in a low-lying coastal area could face damage in the future as sea level rises and the shoreline erodes, even if it meets the current flood zone elevation standards.</p>
<p>This is the problem coastal residents faced during Hurricanes Nicole <a href="https://www.latimes.com/world-nation/story/2022-10-06/apocalypse-in-paradise-after-hurricane-ian-a-low-lying-florida-city-contends-with-rising-water">and Ian</a>. Flooding and erosion, exacerbated by sea-level rise, caused the most damage – not wind. </p>
<p>The dozens of beach houses and condo buildings that <a href="https://www.usnews.com/news/us/articles/2022-11-14/florida-county-puts-damage-from-nicole-at-481-million">became unstable or collapsed</a> in Volusia County during Hurricane Nicole might have seemed fine originally. But as the climate changes, the coastal environment changes, too, and one hurricane could render the building vulnerable. Hurricane Ian damaged sea walls in Volusia County, and some <a href="https://www.news-journalonline.com/story/news/2022/11/10/tropical-storm-nicoles-fury-washes-away-homes-wilbur-sea/8323351001/">couldn’t be repaired before Nicole</a> struck. </p>
<h2>How to minimize the risk</h2>
<p>The damage in the Daytona area in 2022 and the <a href="https://miamisao.com/wp-content/uploads/2021/12/GRAND-JURY_202112151434-1.pdf">deadly collapse</a> a year earlier of a condo tower in Surfside should be a wake-up call for all coastal communities.</p>
<p><a href="https://coast.noaa.gov/digitalcoast/topics/vulnerability-assessments.html">Data and tools</a> can show where coastal areas are most vulnerable. What is lacking are policies and enforcement.</p>
<p>Florida recently began requiring that state-financed constructors conduct <a href="https://floridadep.gov/rcp/florida-resilient-coastlines-program/content/resilience-and-coastal-protection-rules-development">a sea-level impact study</a> before starting construction of a coastal structure. I believe it’s time to apply this new rule to any new construction, regardless of the funding source.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A tall condo building with balconies and erosion almost to the edge of the building" src="https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496327/original/file-20221120-21-vgk04k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">With Hurricane Nicole’s storm surge coinciding with high tide, the waves breached a condo tower’s sea walls in Daytona Beach in November 2022.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/in-this-aerial-view-seawalls-along-condo-buildings-are-news-photo/1440619402">Joe Raedle/Getty Images</a></span>
</figcaption>
</figure>
<p>A comprehensive sea-level impact study requirement should also allow for risk-based enforcement, including barring construction in high-risk areas.</p>
<p>Similarly, vulnerability audits – particularly for multistory buildings built before 2002 – can check the integrity of an existing structure and help spot new environmental risks from sea-level rise and beach erosion. Before 2002, the building standard was low and enforcement was lacking, so many of the materials and the structures used in those buildings aren’t up to the standards of today. </p>
<h2>What property owners can do</h2>
<p>There is a range of <a href="https://www.fema.gov/sites/default/files/documents/fema_protect-your-home-from-flooding-brochure_2020.pdf">techniques</a> homeowners can use to fortify homes from flood risks.</p>
<p>In some places, that may mean <a href="https://cpo.noaa.gov/News/ArtMID/7875/ArticleID/2059/Elevating-Houses-Can-Protect-Against-Damaging-Floods-But-How-High-is-High-Enough">elevating the house</a> or improving the lot grading so surface water runs away from the building. Installing a sump pump and remodeling with storm-resistant building materials can help.</p>
<p><a href="https://www.fema.gov/sites/default/files/documents/fema_protect-your-home-from-flooding-brochure_2020.pdf">FEMA</a> suggests other measures to protect against coastal erosion, such as replenishing beach sand, strengthening sea walls and anchoring the home. Engineering can help communities, temporarily at least, through sea walls, ponds and increased drainage. But in the long term, communities will have to assess the vulnerability of coastal areas. Sometimes the answer is <a href="https://theconversation.com/managed-retreat-done-right-can-reinvent-cities-so-theyre-better-for-everyone-and-avoid-harm-from-flooding-heat-and-fires-163052">to relocate</a>.</p>
<p>However, there’s a disturbing trend after hurricanes, and we’re seeing it with Ian: Many damaged areas see lots of money pouring in to rebuild in the same vulnerable locations. An important question communities should be asking is, if these are already in high-risk areas, why rebuild in the same place?</p><img src="https://counter.theconversation.com/content/194492/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zhong-Ren Peng receives funding from National Science Foundation, Florida Sea Grant, and Florida Department of Transportation. </span></em></p>Dozens of homes near Daytona Beach collapsed or were left unstable when Hurricane Nicole struck. Here’s what can be done to reduce that kind of risk.Zhong-Ren Peng, Professor of Urban and Regional Planning, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1863652022-10-12T15:49:24Z2022-10-12T15:49:24ZCoastal erosion is unstoppable – so how do we live with it?<figure><img src="https://images.theconversation.com/files/489341/original/file-20221012-26-hll9p1.JPG?ixlib=rb-1.1.0&rect=0%2C0%2C3888%2C2590&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Sophie Day</span>, <span class="license">Author provided</span></span></figcaption></figure><p>A record storm surge in 1953 devastated much of eastern England’s coast, prompting prolific investment in concrete sea walls, wooden groynes and other engineered structures designed to protect the coastline from erosion. These measures brought a reassuring sense of permanence for people in previously risky locations. Houses atop sandy cliffs and tucked behind or among sand dunes went from being holiday homes to permanent residences, and new homes were built nearby. </p>
<p>But decades later, the east coast and other parts of England are still eroding – rapidly in some places – despite efforts to hold the coastline in place. </p>
<p>England has some of the <a href="https://www.gov.uk/government/publications/national-flood-and-coastal-erosion-risk-management-strategy-for-england--2">fastest eroding coastline</a> in Europe, particularly along the Norfolk and Yorkshire coasts. Historical records show that England’s soft and sandy east coast has always been subject to retreat. The numerous <a href="https://www.edp24.co.uk/news/weird-nofolk-ghost-bells-haunted-eccles-1562000">lost villages</a> beneath the North Sea are testament to this. </p>
<figure class="align-center ">
<img alt="A beach lined with wooden groynes and other structures." src="https://images.theconversation.com/files/489345/original/file-20221012-14-ql1ktx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/489345/original/file-20221012-14-ql1ktx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/489345/original/file-20221012-14-ql1ktx.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/489345/original/file-20221012-14-ql1ktx.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/489345/original/file-20221012-14-ql1ktx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/489345/original/file-20221012-14-ql1ktx.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/489345/original/file-20221012-14-ql1ktx.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Sea walls and other structures cannot hold the coastline together forever.</span>
<span class="attribution"><span class="source">Sophie Day</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Back in 2018 the <a href="https://www.theccc.org.uk/publication/managing-the-coast-in-a-changing-climate/">Committee on Climate Change</a>, which advises the UK government, calculated that around 9,000 properties in England are located in areas likely to be lost to coastal erosion by 2025. This number is projected to increase 15-fold by the end of the century, disrupting whole communities as more buildings, roads and farmland inevitably slip into the danger zone.</p>
<h2>Unstoppable – and necessary?</h2>
<p>A growing body of research warns that the speed of coastal erosion will be compounded by sea-level rise and other effects of climate change, such as more extreme storms and prolonged wet weather, as waterlogged soils increase the likelihood of sandy cliffs collapsing. Rates of erosion can be roughly but not precisely estimated, due to the complexity of coastal systems and uncertainty regarding how the effects of climate change will manifest. </p>
<figure class="align-center ">
<img alt="A paved road ending in a sheer cliff edge." src="https://images.theconversation.com/files/488482/original/file-20221006-12-foygpz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488482/original/file-20221006-12-foygpz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488482/original/file-20221006-12-foygpz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488482/original/file-20221006-12-foygpz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488482/original/file-20221006-12-foygpz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488482/original/file-20221006-12-foygpz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488482/original/file-20221006-12-foygpz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Life in an eroding community can be unpredictable.</span>
<span class="attribution"><span class="source">Sophie Day</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Since the early 1990s, scientists have collected huge amounts of data in order to understand how the wind, waves, tides and storms shape coastlines. The evidence indicates that it is not possible or prudent to stop or delay coastal erosion forever and that in some places, it <a href="https://doi.org/10.1007/s10584-008-9532-8">may even be necessary</a>. </p>
<p>This is because when soft cliffs such as those along the east of England retreat, they release a lot of sand which is deposited on nearby beaches, making them higher and wider. High and wide beaches absorb the energy of waves, giving some protection to cliffs, dunes and sea walls from coastal erosion and flooding. </p>
<p>The chief executive of the Environment Agency for England recently said it is inevitable that at some point communities will have to <a href="https://www.gov.uk/government/news/environment-agency-sets-out-roadmap-for-more-flood-and-climate-resilient-nation">move back from the coast</a>. So what does this mean for people who live in places where coastal erosion is accelerating, or where it can no longer be stopped?</p>
<p>At Happisburgh in north Norfolk for example, a section of old and damaged sea defences had to be removed in the 1990s to avert dangerous collapse. Rapid erosion of the beach and cliffs since the early 2000s has meant homes in this village being steadily demolished as the coastline retreats. As yet there are no arrangements to compensate people here, or other government policies to help them adapt.</p>
<figure class="align-center ">
<img alt="A series of collapsed houses along a sandy outcrop." src="https://images.theconversation.com/files/488485/original/file-20221006-19-rx1fs1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488485/original/file-20221006-19-rx1fs1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488485/original/file-20221006-19-rx1fs1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488485/original/file-20221006-19-rx1fs1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488485/original/file-20221006-19-rx1fs1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488485/original/file-20221006-19-rx1fs1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488485/original/file-20221006-19-rx1fs1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Uprooted.</span>
<span class="attribution"><span class="source">Sophie Day</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Living with coastal erosion</h2>
<p>It is important to be realistic: homes, roads and other things which knit some coastal communities together will need to be relocated inland away from danger – and soon. But doing this is far from simple, and will certainly be <a href="https://www.pnas.org/doi/full/10.1073/pnas.1222469111">costly</a>. </p>
<p>Ideally, the kind of investment which erected coastal defences in the aftermath of the 1953 storm surge would be mobilised today to help these places move. This is a pressing issue – letting crisis and despair characterise life for coastal communities on the edge is unsustainable and unfair.</p>
<p>Slowly, things are changing. A network of coastal communities, local authority officers and politicians, academics and others have worked since the early 2000s to argue for what is needed to cope with and prepare for coastal erosion around England and Wales. Now, a new <a href="https://engageenvironmentagency.uk.engagementhq.com/hub-page/fcrmfund">pulse of government funding</a> could test these ideas so that in future, no community feels abandoned to the sea. </p>
<figure class="align-center ">
<img alt="An abandoned building behind a metal fence." src="https://images.theconversation.com/files/488483/original/file-20221006-12-h8kp16.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488483/original/file-20221006-12-h8kp16.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488483/original/file-20221006-12-h8kp16.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488483/original/file-20221006-12-h8kp16.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488483/original/file-20221006-12-h8kp16.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488483/original/file-20221006-12-h8kp16.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488483/original/file-20221006-12-h8kp16.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Eroding coastal communities need reassurance and support.</span>
<span class="attribution"><span class="source">Sophie Day</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Part of this work will be to begin the transition in eroding towns and villages on England’s east coast from a state of crisis to one in which people can begin to live feeling safe and confident. It must be systematically worked out how communities can move away from risky areas while maintaining homes, utilities and services, as well as preserving local heritage, culture and each place’s unique character. </p>
<p>As academics working alongside government agencies, our next challenge will be ensuring these time-limited projects translate into robust national policy and funding. Coastal erosion cannot be stopped, so we must help everyone relearn how to live with it.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<p class="fine-print"><em><span>Sophie Day receives funding from North Norfolk District Council (part of Coastal Partnership East) to support a part-time research secondment. She is also affiliated with the Tyndall Centre for Climate Change Research. </span></em></p><p class="fine-print"><em><span>Robert James Nicholls is director of the Tyndall Centre for Climate Change Research at the University of East Anglia, He receives funding from the European Union's Horizon 2020 research and innovation programme under the PROTECT project on sea-level rise (grant agreement 869304), the CoClioCo project on coastal climate services (grant agreement 101003598) and the REST-COAST project on coastal restoration (grant agreement 101037097). He also receives funding under the EPSRC-funded Infrastructure for Port And Coastal cities and Towns network (iPACT) (EP/W033933/1). He has contributed to research led by JBA funded by the Environment Agency to develop metrics concerning flood and coastal change resilience. </span></em></p>Moving entire communities threatened by rising seas isn’t as far-fetched as it sounds.Sophie A. Day, Senior Research Associate in Environmental Sciences, University of East AngliaRobert James Nicholls, Professor of Climate Adaptation, University of East AngliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1919412022-10-07T04:26:32Z2022-10-07T04:26:32ZThe wild weather of La Niña could wipe out vast stretches of Australia’s beaches and sand dunes<p>Australians along the east cost are bracing for yet another round of heavy rainfall this weekend, after a band of stormy weather soaked <a href="https://theconversation.com/on-our-wettest-days-stormclouds-can-dump-30-trillion-litres-of-water-across-australia-191949">most of the continent</a> this week. </p>
<p>The Bureau of Meteorology has <a href="https://www.youtube.com/watch?v=QUsNQ_-fNbM&ab_channel=BureauofMeteorology">alerted</a> southern inland Queensland, eastern New South Wales, Victoria and northern Tasmania to ongoing flood risks, as the rain falls on already flooded or saturated catchments. </p>
<p>This widespread wet weather heralds <a href="https://theconversation.com/la-nina-3-years-in-a-row-a-climate-scientist-on-what-flood-weary-australians-can-expect-this-summer-190542">Australia’s rare third</a> back-to-back La Niña, which goes hand-in-hand with heavy rain. There is, however, another pressing issue arising from La Niña events: coastal erosion.</p>
<p>The wild weather associated with La Niña will drive more erosion along Australia’s east coast – enough to wipe out entire stretches of beaches and dunes, if all factors align. So, it’s important we heed lessons from past storms and plan ahead, as climate change <a href="https://theconversation.com/2022s-supercharged-summer-of-climate-extremes-how-global-warming-and-la-nina-fueled-disasters-on-top-of-disasters-190546">will only exacerbate</a> future coastal disasters.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/QUsNQ_-fNbM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Ongoing flood risk for eastern Australia |
Bureau of Meteorology.</span></figcaption>
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<h2>How La Niña batters coastlines</h2>
<p>La Niña is associated with warmer waters in the western Pacific Ocean, which increase storminess off Australia’s east coast. Chances of a higher number of tropical cyclones increase, as do the chances of cyclones travelling further south and further inland, and of more frequent passages of east coast lows.</p>
<p>Australians had a taste of this in 1967, when the Gold Coast was hit by the largest storm cluster on record, made up of four cyclones and three east coast lows within six months. 1967 wasn’t even an official La Niña year, with the index just below the La Niña threshold.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/la-nina-3-years-in-a-row-a-climate-scientist-on-what-flood-weary-australians-can-expect-this-summer-190542">La Niña, 3 years in a row: a climate scientist on what flood-weary Australians can expect this summer</a>
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<p>Such frequency didn’t allow beaches to recover between storms, and the overall erosion was unprecedented. It <a href="https://impact.griffith.edu.au/seawall-engineering/">forced many</a> local residents to use anything on hand, even cars, to protect their properties and other infrastructure.</p>
<p>Official La Niña events occurred soon after. This included a double-dip La Niña between 1970 and 1972, followed by a triple-dip La Niña between 1973 and 1976. </p>
<p>These events fuelled two cyclones in 1972, two in 1974 and one in 1976, wreaking havoc along the entire east coast of Australia. Indeed, 1967 and 1974 are considered <a href="https://www.dailytelegraph.com.au/newslocal/northern-beaches/one-of-the-storms-that-hit-us-in-1974-was-among-the-three-worst-since-white-settlement/news-story/0cd5ca874d6b37206762d8485e4eb442">record years</a> for storm-induced coastal erosion.</p>
<p>Studies show the extreme erosion of 1974 was caused by a combination of large waves coinciding with <a href="https://ro.uow.edu.au/cgi/viewcontent.cgi?article=1066&context=scipapers">above-average high tides</a>. It took over ten years for the sand to come back to the beach and for <a href="https://www.jstor.org/stable/4300263">dunes to recover</a>. However, <a href="https://www.nature.com/articles/s43247-022-00437-2">recent studies</a> also show single extreme storms can bring back considerable amounts of sand from deeper waters.</p>
<p>La Niña also modifies the direction of waves along the east coast, resulting in waves approaching from a more easterly direction (<a href="https://www.surfline.com/surf-news/forecaster-blog-la-nina-conditions-mean-surf/97904">anticlockwise</a>). </p>
<p>This subtle change has huge implications when it comes to erosion of otherwise more sheltered <a href="https://au.news.yahoo.com/how-la-nina-may-damage-queensland-tourist-hot-spots-041805874.html">north-facing beaches</a>. We saw this during the recent, and relatively weaker, double La Niña of 2016-18. </p>
<p>In 2016, an east coast low of only moderate intensity produced extreme erosion, similar to that of 1974. Scenes of destruction along NSW – including a collapsed backyard pool on <a href="https://www.wrl.unsw.edu.au/news/wrl-coastal-engineers-document-the-worst-erosion-at-collaroy-since-1974">Collaroy Beach</a> – are now <a href="https://www.abc.net.au/news/2016-06-06/nsw-weather-large-waves-hit-collaroy-coast/7479846#:%7E:text=NSW%20weather%3A%20Collaroy%20swimming%20pool%20collapses%20as%20giant%20waves%20hit%20beachfront%20houses,-Posted%20Sun%205&text=Waves%20up%20to%208%20metres,as%20wild%20weather%20battered%20NSW.">iconic</a>. </p>
<p><a href="https://www.nature.com/articles/s41598-017-05792-1">This is largely</a> because wave direction deviated from the average by 45 degrees anticlockwise, during winter solstice spring tides when water levels are higher. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/2022s-supercharged-summer-of-climate-extremes-how-global-warming-and-la-nina-fueled-disasters-on-top-of-disasters-190546">2022's supercharged summer of climate extremes: How global warming and La Niña fueled disasters on top of disasters</a>
</strong>
</em>
</p>
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<h2>All ducks aligned?</h2>
<p>The current triple-dip La Niña started in 2020. Based on Australia’s limited record since 1900, we know the final events in such sequences tend to be the weakest. </p>
<p>However, when it comes to coastal hazards, history tells us smaller but more frequent storms can cause as much or more erosion than one large event. This is mostly about the combination of storm direction, sequencing and high water levels.</p>
<p>For example, Bribie Island in Queensland was hit by relatively large easterly waves from ex-Tropical Cyclone Seth earlier this year, coinciding with above-average high tides. This caused the island to <a href="https://www.abc.net.au/news/2022-01-27/bribie-island-changes-could-create-new-caloundra-bar/100777038#:%7E:text=Ex%2DTropical%20Cyclone%20Seth%20has,splitting%20the%20island%20in%20two.">split in two</a> and form a 300-metre wide passage of seawater. </p>
<p>Further, the prolonged period of easterly waves since 2020 has already taken a toll on beaches and dunes in Australia. </p>
<p>Traditionally, spring is the season when sand is transported onshore under fair-weather waves, building back wide beaches and tall dunes nearest to the sea. However, beaches haven’t had time to fully recover from the previous two years, which makes them more vulnerable to future erosion.</p>
<p>Repeated <a href="https://www.usc.edu.au/about/structure/schools/school-of-science-technology-and-engineering/coast4d">elevation measurements</a> by our team and citizen scientists along beaches in the Sunshine Coast and Noosa show shorelines have eroded more than 10m landwards since the beginning of this year. As the photo below shows, 2-3m high erosion scarps (which look like small cliffs) have formed along dunes due to frequent heavy rainfalls and waves.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488701/original/file-20221007-18-mmjydr.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dune scarps at a beach in Noosa.</span>
<span class="attribution"><span class="source">Javier Leon</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>On the other hand, we can also see that the wet weather has led to greater growth of vegetation on dunes, such as native spinifex and dune bean.</p>
<p>Experiments in laboratory settings show dune vegetation can dissipate up to 40-50% of the water level reached as a result of waves, and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0272771418307583">reduce erosion</a>. But whether this increase in dune vegetation mitigates further erosion remains to be seen.</p>
<h2>A challenging future</h2>
<p>The chances of witnessing coastal hazards similar to those in 1967 or 1974 in the coming season are real and, in the unfortunate case they materialise, we should be ready to act. Councils and communities need to prepare ahead and work together towards recovery if disaster strikes using, for example, sand nourishment and sandbags.</p>
<p>Looking ahead, it remains essential to further our understanding about coastal dynamics – especially in a <a href="https://www.abc.net.au/news/2022-09-03/gold-coast-no-stranger-to-beach-erosion/101381812#:%7E:text=a%20huge%20challenge-,Millions%20spent%20to%20protect%20Gold%20Coast%20beaches%2C%20but,change%20poses%20a%20huge%20challenge&text=In%201967%2C%20Gold%20Coast%20beaches,and%20ruined%20the%20tourist%20season.">changing climate</a> – so we can better manage densely populated coastal regions. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-fuelled-wave-patterns-pose-an-erosion-risk-for-developing-countries-184064">Climate-fuelled wave patterns pose an erosion risk for developing countries</a>
</strong>
</em>
</p>
<hr>
<p>After all, much of what we know about the dynamics of Australia’s east coast has been supported by coastal monitoring programs, which were implemented <a href="https://www.publications.qld.gov.au/dataset/coastal-observation-program-engineering">along Queensland</a> and NSW after the 1967 and 1974 storms. </p>
<p>Scientists predict that La Niña conditions along the east coast of Australia – such as warmer waters, higher sea levels, stronger waves and more waves coming from the east – will become <a href="https://theconversation.com/climate-fuelled-wave-patterns-pose-an-erosion-risk-for-developing-countries-184064">the norm under climate change</a>. </p>
<p>It’s crucial we start having a serious conversation about coastal adaptation strategies, including implementing a <a href="https://www.usc.edu.au/about/unisc-news/news-archive/2022/january/coastal-erosion-may-force-retreat-from-the-sea#:%7E:text=Giving%20up%20land%20to%20the,of%20the%20Sunshine%20Coast%20researcher.">managed retreat</a>. The longer we take, the higher the costs will be.</p><img src="https://counter.theconversation.com/content/191941/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Javier Leon receives funding from Noosa Council and The Queensland Earth Observation (EO) Hub, a partnership between the Queensland Government and SmartSat Cooperative Research Centre (CRC)</span></em></p>We must heed lessons from past storms and plan ahead, as climate change will only exacerbate future coastal disasters.Javier Leon, Senior lecturer, University of the Sunshine CoastLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1908982022-09-19T11:45:55Z2022-09-19T11:45:55ZTyphoon Merbok, fueled by unusually warm Pacific Ocean, pounded Alaska’s vulnerable coastal communities at a critical time<figure><img src="https://images.theconversation.com/files/485177/original/file-20220918-52219-igrjib.jpg?ixlib=rb-1.1.0&rect=28%2C7%2C1649%2C1058&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A satellite image shows how vast the remnants of Typhoon Merbok were as the storm hit the Alaska coast.</span> <span class="attribution"><a class="source" href="https://twitter.com/NWSFairbanks/status/1571054643383533569">National Weather Service</a></span></figcaption></figure><p><em>The powerful remnants of Typhoon Merbok pounded Alaska’s western coast on Sept. 17, 2022, pushing homes off their foundations and tearing apart protective berms as water flooded communities.</em> </p>
<p><em>Storms aren’t unusual here, but Merbok built up over unusually warm water. Its <a href="https://twitter.com/NWSOPC/status/1570883906794311682">waves reached 50 feet</a> over the Bering Sea, and its storm surge sent water levels into communities at <a href="https://twitter.com/AlaskaWx/status/1571266836771270659">near record highs</a> along with near hurricane-force winds.</em></p>
<p><em>Merbok also hit during the fall subsistence harvest season, when the region’s Indigenous communities are stocking up food for the winter. Rick Thoman, a <a href="https://news.uaf.edu/expertsguide/rick-thoman/">climate scientist at the University of Alaska Fairbanks</a>, explained why the storm was unusual and the impact it’s having on coastal Alaskans.</em></p>
<h2>What stands out the most about this storm?</h2>
<p>It <a href="https://www.weather.gov/media/arh/RN-05-0003.pdf">isn’t unusual</a> for typhoons to affect some portion of Alaska, typically in the fall, but Merbok was different. </p>
<p>It <a href="https://twitter.com/Climatologist49/status/1571218582293610496/photo/1">formed in a part of the Pacific</a>, far east of Japan, where historically few typhoons form. The water there is typically too cold to support a typhoon, but right now, we have extremely warm water in the north-central Pacific. Merbok traveled right over waters that are the warmest on record going back about 100 years.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map shows warm waters off Japan and Russia's Kamchatka region." src="https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485179/original/file-20220918-51705-mljo8r.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Sea surface temperatures show unusually warm water over the eastern Pacific Ocean, where Typhoon Merbok passed through.</span>
<span class="attribution"><a class="source" href="https://uaf-accap.org/">Alaska Center for Climate Assessment</a></span>
</figcaption>
</figure>
<p>The Western Bering Sea, closer to Russia, has been running above normal sea surface temperature since last winter. The Eastern Bering Sea – the Alaska part – has been normal to slightly cooler than normal since spring. That temperature difference in the Bering Sea helped to feed the storm and was probably part of the reason the storm intensified to the level it did. </p>
<p>When Merbok moved in to the Bering Sea, it wound up being by far the strongest storm this early in the autumn. We’ve had stronger storms, but they typically occur in October and November.</p>
<h2>Did climate change have a bearing on the storm?</h2>
<p>There’s a strong likelihood that Merbok was able to form where it did because of the <a href="https://www.ncei.noaa.gov/cag/global/time-series/globe/ocean/12/12/1880-2022">warming ocean</a>.</p>
<p>With warm ocean water, there’s <a href="https://climate.nasa.gov/ask-nasa-climate/3143/steamy-relationships-how-atmospheric-water-vapor-amplifies-earths-greenhouse-effect/">more evaporation going in the atmosphere</a>. Because all the atmospheric ingredients came together, Merbok was able to bring that very warm moist air along with it. Had the ocean been a <a href="https://www.ncei.noaa.gov/cag/global/time-series/globe/ocean/12/12/1880-2022">temperature more typical of 1960</a>, there wouldn’t have been as much moisture in the storm.</p>
<figure class="align-center ">
<img alt="Bar chart showing temperatures rising" src="https://images.theconversation.com/files/485199/original/file-20220919-62263-2t01r9.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485199/original/file-20220919-62263-2t01r9.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=360&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485199/original/file-20220919-62263-2t01r9.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=360&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485199/original/file-20220919-62263-2t01r9.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=360&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485199/original/file-20220919-62263-2t01r9.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=453&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485199/original/file-20220919-62263-2t01r9.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=453&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485199/original/file-20220919-62263-2t01r9.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=453&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Global ocean temperatures have been rising. The bars show how annual temperatures departed from the 20th century average.</span>
<span class="attribution"><a class="source" href="https://www.ncei.noaa.gov/cag/global/time-series/globe/ocean/12/12/1880-2022">NOAA</a></span>
</figcaption>
</figure>
<h2>How extreme was the flooding compared to past storms?</h2>
<p>The most outstanding feature as far as impact is the tremendous area that was damaged. All coastal regions north of Bristol Bay to just beyond the Bering Strait – hundreds of miles of coastline – had some impact. </p>
<p>At Nome – one of the very few places in western Alaska where we have long-term ocean level information – the ocean was <a href="https://twitter.com/AlaskaWx/status/1571266836771270659">10.5 feet</a> (3.2 meters) above the low-tide line on Sept. 17, 2022. That’s the highest there in nearly half a century, since the historic storm of <a href="https://doi.org/10.1080/00431672.1975.9931740">November 1974</a>.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1571514507041595392"}"></div></p>
<p>In <a href="https://www.nytimes.com/2022/09/17/us/alaska-storm.html">Golovin</a> and <a href="https://www.ktoo.org/2022/09/17/powerful-storm-slams-western-alaska/">Newtok</a>, multiple houses floated off their foundations and are no longer habitable.</p>
<p><a href="https://savingplaces.org/stories/fighting-the-rising-tide-in-shaktoolik-alaska#.Yyd7pHbML8A">Shaktoolik</a> lost its protective berm, which is very bad news. Prior to building the berm, the community’s freshwater supply was easily inundated with saltwater. The community is now at greater risk of flooding, and even a moderate storm could inundate their fresh water supply. They can rebuild it, but how fast is a matter of time and money and resources. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1571310275739156480"}"></div></p>
<p>Another important impact is to hunting and fishing camps along the coasts. Because of the <a href="https://www.nps.gov/gis/storymaps/cascade/v1/index.html?appid=42e0af0fd1ab485596a0475d186a0919">region’s subsistence economy</a>, those camps are crucial, and they are expensive to rebuild. </p>
<p>There are no roads into these coastal communities, and <a href="https://www.ktoo.org/2022/02/21/construction-supply-chain-woes-in-rural-alaska/">getting lumber for rebuilding</a> homes and these camps is difficult. And we’re moving into typically the stormiest time of year, which makes recovery harder and planes often can’t land.</p>
<p>Lots of places also lost power and cell phone communication. The power in these remote areas is generated in the community – if that goes out there is no alternative. People lose power to their freezers, which they’re stocking up for the winter. Towns might have one grocery store, and if that can’t open or loses power, there is no other option. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1571235158342373383"}"></div></p>
<p>Winter is coming, and the time when it’s feasible to make repairs is running short. This is also the middle of hunting season, which in western Alaska is not recreation – it’s how you feed your family. These are almost all predominantly or almost exclusively Indigenous communities. Repairs are going to take time away for subsistence hunters, so all of these things are coming together at once. </p>
<h2>Does the lack of sea ice as a buffer make a difference for erosion?</h2>
<p>Historically, with storms later in the season, even a small bit of sea ice can offer protection to dampen the waves. But there’s <a href="http://nsidc.org/arcticseaicenews/2022/09/the-arctics-bald-spot/">no ice in the Bering Sea</a> at all this time of year. The full wave action pounds right to the beach. </p>
<p>As sea ice <a href="https://climate.nasa.gov/vital-signs/arctic-sea-ice/">declines with warming global temperatures</a>, communities will see more damage from storms later in the year, too.</p>
<h2>Are there lessons from this storm for Alaska?</h2>
<p>As bad as this storm was, and it was very bad, others will be coming. This is a stormy part of the world, and state and federal governments need to do a better job of communicating risks and helping communities and tribes ahead of time. </p>
<p>That might mean evacuating vulnerable people. Because if you wait until it’s certain that there’s a problem, it’s too late. Almost all of these communities are isolated. </p>
<p>I would say this is a classic case of large-scale weather models showing a general idea of the risk far in advance, but it takes longer to respond for isolated communities like those in rural Alaska. By Sept. 12, <a href="https://twitter.com/Climatologist49/status/1571218582293610496">Merbok’s storm track was clear</a>, but if communities aren’t briefed until a day or two days before the storm, there isn’t enough time for them to fully prepare.</p><img src="https://counter.theconversation.com/content/190898/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rick Thoman does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Most of the flooded communities are Indigenous and rely on subsistence hunting that residents would normally be doing right now. Recovering from the damage will make that harder.Rick Thoman, Alaska Climate Specialist, University of Alaska FairbanksLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1847212022-07-20T15:00:15Z2022-07-20T15:00:15ZSt. Lawrence shoreline erosion: We must work with, not against, nature<figure><img src="https://images.theconversation.com/files/474688/original/file-20220718-57395-z4bm3n.jpg?ixlib=rb-1.1.0&rect=26%2C33%2C4459%2C2957&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Local communities, researchers, governments and businesses are working together to identify coastal erosion risks and find sustainable solutions.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>The St. Lawrence riverbanks are eroding. This has an impact on infrastructure, economy and <a href="https://theconversation.com/hurricanes-to-deliver-a-bigger-punch-to-coasts-113246">inhabitants’ well-being</a>. It exposes communities to flooding and can destroy local ecosystems.</p>
<p>Under the threat of a climate catastrophe, an in-depth reflection is essential to adapt to the changing climate in the St. Lawrence.</p>
<p>In Prince Edward Island, the average erosion rate is about <a href="https://www.nrcan.gc.ca/climate-change/impacts-adaptations/canadas-marine-coasts-changing-climate/18388">0.3 metres per year</a>. In New Brunswick, it is about 0.5 metres per year. In Quebec, it is closer to two metres per year! </p>
<p>This rate of erosion is expected to increase as climate change raises sea levels, bringing water closer to local communities. More frequent and stronger storms will generate larger waves and the reduction in sea ice coverage will give winter storms access to the coast, where the land comes into contact with the sea.</p>
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<img alt="" src="https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em>This article is part of our series, <a href="https://theconversation.com/ca-fr/topics/fleuve-saint-laurent-116908">The St. Lawrence River: In depth</a>.
Don’t miss new articles on this mythical river of remarkable beauty. Our experts look at its fauna, flora and history, and the issues it faces. This series is brought to you by <a href="https://theconversation.com/ca-fr">La Conversation</a>.</em></p>
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<p>The latest report from the <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/">United Nations’ Intergovernmental Panel on Climate Change (IPCC)</a> calls for transformative adaptation, to completely rethink the way we adapt to climate change to include more sustainable solutions.</p>
<p>As professors of coastal engineering, we work to develop resilient solutions to adapt to climate change in coastal and estuarial environments. We work with communities, businesses and non-profit organizations to better understand how natural systems can be used to protect coasts from erosion and flooding.</p>
<h2>Traditional approaches are no longer appropriate</h2>
<p>Almost all — 97 per cent — of Quebec’s coastal infrastructure is composed of <a href="https://www.sciencedirect.com/science/article/abs/pii/S0964569120302672">“hard”</a> structures. You can see these dikes and barriers along the St. Lawrence River, designed to maintain or extend the coastline.</p>
<p>This approach is advocated worldwide, with most design manuals, research and case studies focusing on hard infrastructure; it has been <a href="https://bioone.org/journals/journal-of-coastal-research/volume-2005/issue-211/03561.1/Panorama-of-the-History-of-Coastal-Protection/10.2112/03561.1.full">used for centuries</a>. These types of infrastructure-based adaptation methods are well established and have a proven track record in solving short-term problems without occupying significant shoreline.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Construction equipment sits atop an ocean barrier made of large rocks" src="https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/457005/original/file-20220407-26-jtyn21.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Hard infrastructure, used around the world for centuries, serves to maintain or enhance the coastline.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>The problem with hard infrastructure is that it does not adapt to the changing climate. As such, it often requires maintenance and restoration, and can hinder the natural evolution of the coastline. This is known as coastal squeeze. </p>
<p>Coastal squeeze is particularly problematic where coastlines have been designed to treat acute symptoms (such as local flooding) rather than address the underlying problem. These limits, if not properly managed, tend to shift or <a href="https://link.springer.com/chapter/10.1007/978-3-030-40552-6_4">worsen the problem</a>.</p>
<p>Examples can be seen in Kamouraska Bay, in the St. Lawrence River, where land recovery with dikes for agricultural use has resulted in the loss of three-quarters of the marsh ecosystem over the past century. In addition, these dikes were breached during recent floods, trapping salt water on farmland.</p>
<h2>Working with nature in a changing climate</h2>
<p>The implications of climate change are becoming increasingly obvious. Its effects are being felt throughout the St. Lawrence: beaches are eroding and more communities are at risk of flooding. Communities must find ways to adapt.</p>
<p>One of the key strategies proposed to adapt to the impacts of climate change is that of “nature-based solutions”. These are coastal protection systems designed to include or mimic natural ecosystems to protect and stabilize the coastline.</p>
<p>One example of a nature-based solutions application is that of <a href="https://www.pc.gc.ca/en/pn-np/qc/forillon/nature/conservation/cote-coastal">Forillon National Park</a>, where hard infrastructure protecting a road had disrupted natural coastal dynamics and led to the loss of the local beach. Researchers worked with the park department to move the road away from the coast and restore the beach vegetation to help the beach to recover naturally.</p>
<figure class="align-center ">
<img alt="A sign reads 'coastline under construction' in front of bushes and shrubs, with a beach and water in the background." src="https://images.theconversation.com/files/456998/original/file-20220407-25-jl5mjb.jpeg?ixlib=rb-1.1.0&rect=11%2C9%2C1541%2C1172&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/456998/original/file-20220407-25-jl5mjb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/456998/original/file-20220407-25-jl5mjb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/456998/original/file-20220407-25-jl5mjb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/456998/original/file-20220407-25-jl5mjb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/456998/original/file-20220407-25-jl5mjb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/456998/original/file-20220407-25-jl5mjb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Major infrastructures (roads) and tourist destinations (national parks) are increasingly exposed to the constraints of erosion – Bic National Park.</span>
<span class="attribution"><span class="source">(Jacob Stolle)</span>, <span class="license">Fourni par l'auteur</span></span>
</figcaption>
</figure>
<p>Another example is the realignment of the <a href="https://www.transcoastaladaptations.com/making-room-for-wetlands">Belcher Street dike</a> in Nova Scotia. For this project, researchers worked with farmers and local governments to relocate a dike so that flood water could be diverted from the local community to areas that once held the river overflow water. As a result, it also permitted water to return to the floodplain, restoring the local wetland ecosystem.</p>
<h2>A multidisciplinary and participatory approach</h2>
<p>Nature-based solutions are not simply about planting plants and then walking away. It is a comprehensive system based on a multidisciplinary and participatory approach that entails working with ecosystems, communities and local economies to find solutions.</p>
<p>This can range from protecting local wetlands to greening hard infrastructure to boost <a href="https://www.csagroup.org/article/research/nature-based-solutions-for-coastal-and-riverine-flood-and-erosion-risk-management/">ecological value</a>, for example to provide habitats for oysters and fish species.</p>
<p>Our research team is busy testing solutions co-developed by multidisciplinary groups in <a href="https://nrc.canada.ca/en/research-development/research-collaboration/programs/ocean-program-coastal-resilience-technology-theme">our large wave channel</a>. This channel, the largest in North America, allows us to test and optimize solutions and technologies in a controlled environment before they are implemented in the real world.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Large wave channel" src="https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/457001/original/file-20220407-19484-fjzq0x.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The largest wave channel in North America is designed to test solutions developed through a multidisciplinary and participatory approach.</span>
<span class="attribution"><span class="source">(Jacob Stolle)</span>, <span class="license">Fourni par l'auteur</span></span>
</figcaption>
</figure>
<p>For example, we are currently studying how coastal marsh restoration can protect against coastal erosion and reduce wave energy. Thanks to knowledge gained from the experiments, we can develop guidelines to help engineers integrate marsh restoration into future projects.</p>
<h2>Adapting solutions for the St. Lawrence</h2>
<p>In general, the biggest challenge to implementing nature-based solutions is the lack of understanding and guidance regarding their performance in cold regions like Canada. Several guidelines have recently been published at the <a href="https://ewn.erdc.dren.mil/?page_id=4351">international level</a> but they tend to be fairly high-level without specific details on how to implement them. </p>
<p>Therefore, as researchers, we must test solutions relevant to the St. Lawrence in the laboratory or in simulation models to predict how they will actually react.</p>
<p>It is also important to set up comprehensive and multidisciplinary monitoring programs after the implementation of these solutions to develop a deeper understanding of how they work.</p>
<p>While <a href="https://www.quebec.ca/gouvernement/politiques-orientations/plan-de-protection-du-territoire-face-aux-inondations">provincial</a> and <a href="https://www.canada.ca/en/environment-climate-change/services/environmental-funding/programs/nature-smart-climate-solutions-fund.html">federal</a> governments have begun to put in place long-term programs incorporating sustainable solutions, it is important to realize that the shores of the St. Lawrence are already eroding and will continue to erode. </p>
<p>We must act quickly to solve tomorrow’s problem.</p><img src="https://counter.theconversation.com/content/184721/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jacob Stolle has received funding from the National Research Council Canada and the Natural Sciences and Engineering Research Council of Canada.</span></em></p><p class="fine-print"><em><span>Damien Pham-Van-Bang is a member of various learned societies such as IAHR (International Association Hydraulic Research), AFVL (Association Francaise de Velocimétrie Laser), PIANC (Permanent International Association Navigation Congress), RFRC (Reseau Francais de Recherche Côtière), IAEA (International Atomic Energy Association. It has received funding from ANR (National Research Agency, FR), EDF (Electricité de France), CNRS (National Center for Scientific Research), FRQ (Fonds Recherche Québec), RQM (Reseau Quebec Maritime ), IFQM (France-Quebec Maritime Institute), CRSNG (Natural Sciences and Engineering Research Council), CGQ (Quebec Geological Commission), ROBVQ (Quebec Watershed Observatory Network), MTQ (Min. Transport Quebec).</span></em></p>Coastal erosion along the St. Lawrence River has economic, social and cultural impacts.Jacob Stolle, Professeur adjoint, hydrodynamique côtière et fluviale, Institut national de la recherche scientifique (INRS)Damien Pham-Van-Bang, Associate professor, Institut national de la recherche scientifique (INRS)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1825712022-05-23T13:24:25Z2022-05-23T13:24:25ZRising sea levels are driving faster erosion along Senegal’s coast<figure><img src="https://images.theconversation.com/files/463689/original/file-20220517-20-wav7w5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Destroyed buildings along an eroded coastline in Bargny, Senegal.
</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/women-walk-past-destroyed-buildings-along-the-eroded-news-photo/1228661818">Photo by John Wessels / AFP via Getty Images</a></span></figcaption></figure><p>Coastal retreat in West Africa is a pressing problem. The contact between land and sea on coasts produces intense erosion and sedimentation processes. When erosion is more intense than deposits of soil and sand, the sea advances and the coastline retreats. This can be caused by intense storms, coastal works, sand extraction or the rise in sea level.</p>
<p>The United Nations has recently highlighted the impacts associated with <a href="https://www.unep.org/resources/report/sand-and-sustainability-10-strategic-recommendations-avert-crisis">sand mining</a>, a problem with many environmental and social consequences.</p>
<p>Senegal provides an example of coastal erosion. Between 1954 and 2002, the country’s coastline retreated by an average of 2.2 metres per year, <a href="https://doi.org/10.1007/s11852-020-00742-y">reaching three metres per year between 2014 and 2018</a>. This coastal retreat is destroying houses, tourist buildings and fishing infrastructure, and leading to the disappearance of beaches and the loss of agricultural land.</p>
<p>The advance of the sea is also making <a href="https://www.mdpi.com/2073-4441/10/12/1837">groundwater</a> more saline and unsuitable for human consumption and agriculture. In estuarine areas, an increase in salinity affects <a href="https://www.unep.org/resources/report/global-international-waters-assessment-canary-current-giwa-regional-assessment-41">mangroves and fisheries </a>.</p>
<p>It is important to know what is causing this coastal retreat so that responsibilities can be assigned for dealing with it. There are two dimensions, one local and the other global. </p>
<p>At the local level, some human actions can lead to coastal erosion and beach disappearance. The construction of breakwaters, often in response to erosion, alters the way the sea normally moves sand from one place to another. Although breakwaters solve local problems, they may create new ones: sand deposit in one area occurs at the cost of erosion in another. </p>
<p>Another problem in West Africa is illegal mining of coastal sand, mostly for construction. <a href="https://doi.org/10.1038/s41893-022-00857-0">Sand is in demand, and beaches are an easy source of supply</a>. </p>
<p><a href="https://doi.org/10.1007/978-3-319-06388-1_1">At a global level</a>, <a href="https://climateknowledgeportal.worldbank.org/sites/default/files/2018-10/wb_gfdrr_climate_change_country_profile_for_SEN.pdf">this region is highly affected by climate change</a>. A rise in sea level is becoming <a href="https://www.ipcc.ch/site/assets/uploads/2020/11/TGICA_Fact_Sheet_CMIP5_data_provided_at_the_IPCC_DDC_Ver_1_2016.pdf">more and more pronounced </a>. One of the impacts is an increase of coastal erosion, which affects agriculture, fisheries and tourism. </p>
<p><a href="https://link.springer.com/article/10.1007/s11852-020-00742-y">In a recent study</a> we aimed to evaluate shoreline retreat in a 13km section of Senegal’s coast, in the Palmarin peninsula. We were looking for trends over time and causes. </p>
<p>The study showed an increasing retreat of the coastline over dozens of kilometres, with no local human action to justify it. The main cause is climate change. It is likely there will be significant impacts for the environment, the population and economic activities. There is an urgent need to develop an adaptation plan for this area.</p>
<h2>Palmarin, a classic story of climate change</h2>
<p>We chose to study the Palmarin area because it is highly vulnerable to coastal erosion, land flooding and soil salinisation. Shoreline retreat is already intense. <a href="https://cedb.asce.org/CEDBsearch/record.jsp?dockey=0083162">Previous studies</a> showed <a href="http://article.sapub.org/10.5923.j.ms.20170701.01.html">shoreline retreat rates</a> of 1.20m/year in 1982 and 2.20m/year in 1954–2002.</p>
<p>We looked at the period 2005-2018 and compared our results with earlier estimations and measurements. We used as shoreline retreat indicator the sea erosion front. This is the small scarp between the beach and hinterland, which is easily recognisable in aerial photos. We found an increase of retreat to 2.45 m/year in 2005–2010, 2.60 m/year in 2010–2014 and 3.05 m/year in 2014–2018.</p>
<p>We also assessed the risk of coastal retreat in the short and medium term future. </p>
<p>Our short-term estimates showed probable damage to villages, tourist camps and roads. There is also a significant risk that coastal erosion will connect the sea and the intertidal mud flat areas of the Saloum estuary. This would break up the peninsula into several islands, changing the way that erosion evolves, producing a decline of mangroves and thus threatening fishing. <a href="https://www.int-res.com/articles/cr/6/c006p165.pdf">Mangroves are important spawning areas</a>, so erosion affects fishing, an essential economic resource for the local population.</p>
<p>In the studied area there are currently no coastal defences or sand extraction areas. Therefore, coastal erosion cannot be attributed to human actions. On the other hand, <a href="https://www.ipcc.ch/report/ar1/wg1/sea-level-rise/">sea level rise is indisputable</a> and explains what is happening.</p>
<h2>A global responsibility</h2>
<p><a href="https://www.thenewhumanitarian.org/news/2013/02/01/sand-mining-threatens-homes-and-livelihoods-sierra-leone">Lorries removing sand from a beach</a> make for a media-friendly <a href="https://coastalcare.org/2016/01/senegal-president-asks-the-government-to-take-measures-to-stop-illegal-beach-and-dunes-sand-mining-along-senegal-coast/">image</a>, while a gradual rise in sea level by a few millimetres each year is much more subtle. Yet its effects are devastating. The advance of the sea on the coasts of West Africa can affect hundreds of thousands of people.</p>
<p>Action is needed at both global and local levels to mitigate the effects of coastal retreat. </p>
<p>Locally, works that alter coastal dynamics should be avoided and coastal sand mining should be controlled. Many countries already do this. In Senegal the <a href="https://eiti.org/documents/senegals-2016-mining-code">mining code</a> prohibits sea sand extraction, the gendarmerie combat illegal mining and the government conducts studies to find alternatives to sea sand.</p>
<p>But these measures, which may solve local problems, will not halt the current coastal retreat. Strong global action by all countries is essential to mitigate climate change by drastically reducing greenhouse gas emissions.</p>
<p>Local adaptation measures are also necessary to guarantee the future of the region and its inhabitants. Coastal defences are expensive and don’t stop beaches from disappearing. In many places, it will be necessary to consider moving the population away from the coastline to allow the formation of new beaches. Doing so will require large investments and land occupations, and may affect agriculture and biodiversity.</p>
<p>Climate change is a global process, but each country’s responsibilities are different. Therefore, adaptation to its effects must also be global, and its <a href="https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_FinalDraft_Chapter09.pdf">financing</a> must be commensurate with those responsibilities. </p>
<p>West African countries must avoid the local causes of coastal retreat. But above all, they should get international support to adapt to the social, environmental and economic problems arising from climate change, a global problem for which they are hardly responsible.</p><img src="https://counter.theconversation.com/content/182571/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Álvaro Enríquez de Salamanca does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Coastal erosion in West Africa is a cause for global concern. The global community must rally to address climate change which is causing the retreat.Álvaro Enríquez de Salamanca, Assistant Professor, Universidad Complutense de MadridLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1820392022-05-12T09:02:55Z2022-05-12T09:02:55Z‘Like 20 tip trucks pouring sand on every metre-wide strip’: how extreme storms can replenish beaches, not just erode them<figure><img src="https://images.theconversation.com/files/462641/original/file-20220512-19-kvyhfz.jpg?ixlib=rb-1.1.0&rect=0%2C502%2C1845%2C1030&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption"></span> </figcaption></figure><p><em>Environmental scientists see flora, fauna and phenomena the rest of us rarely do. In this series, we’ve invited them to share their unique <a href="https://theconversation.com/au/topics/photos-from-the-field-92499">photos from the field</a>.</em></p>
<hr>
<p>Extreme storms can cause devastating erosion and leave beachfront houses <a href="https://www.abc.net.au/news/2021-07-16/wamberal-beach-erosion-one-year-on/100295364">teetering on cliff edges</a>. But our <a href="https://www.nature.com/articles/s43247-022-00437-2">new research</a>, published today, finds storms might also help replenish beaches by bringing in new sand from deeper waters.</p>
<p>We studied three extreme storms in Australia, the United Kingdom and Mexico. One, in Sydney in 2016, <a href="https://www.youtube.com/watch?v=e4DxqUshKh4">famously ripped a swimming pool</a> away from a property overlooking the coastline. </p>
<p>For the first time, we’re able to show just how much new sand can be added to a beach in a single storm alone – over 400,000 cubic metres in some cases. That’s equivalent to the <a href="https://www.nature.com/articles/s43017-020-00109-9">typical volumes of sand</a> engineers use to nourish beaches artificially.</p>
<p>As sea levels rise, this natural form of beach replenishment might be an important factor in offsetting some of the damaging effects of climate change on beaches. Yet, with little knowledge of exactly how much sand is moving around offshore, predicting the future of beaches in the coming decades is extremely difficult.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462626/original/file-20220512-19-bzoz4c.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Damaged houses at Collaroy Beach, Sydney in the wake of an extreme storm in June 2016.</span>
<span class="attribution"><span class="source">UNSW Water Research Laboratory</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462627/original/file-20220512-12-arf332.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">While extreme storms can cause major erosion to beachfront properties, they can also bring in new sand from deeper water.</span>
<span class="attribution"><span class="source">UNSW Water Research Laboratory</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Wave after wave</h2>
<p>Violent storm waves strip beaches of sand above the waterline, which often erodes sand dunes. In deeper waters, however, these same waves help stir up sediment lying dormant on the seabed. This sand is then pushed towards the shore and settles as the storm passes.</p>
<p>To study the three storms in Australia, the UK and Mexico, we used high-resolution monitoring equipment including twin engine airplanes, drones and jet skis mounted with an echo-sounder for measuring the seabed.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=367&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=367&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=367&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=462&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=462&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462621/original/file-20220512-22-qljf6d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=462&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The UK survey team measuring sand volumes along the coast of Cornwall.</span>
<span class="attribution"><span class="source">University of Plymouth</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=347&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=347&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=347&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=436&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=436&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462623/original/file-20220512-16-pm0lu1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=436&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A combination of high-resolution survey equipment was used to measure changes to the beach.</span>
<span class="attribution"><span class="source">University of Plymouth</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In Australia, we measured Narrabeen Beach in Sydney. In the UK, we monitored the impact of <a href="https://www.bbc.com/news/uk-26170904">several storms during the winters of 2013-2014</a> and 2015-2016, at Perranporth beach in Cornwall. And in northwest Mexico, we recorded the impact of the 2018-2019 winter on La Mision Beach.</p>
<p>In the time-lapse video below, you can see just how quickly the water can encroach on beachfront houses during extreme storms. Beneath the water surface, however, huge volumes of sand is also moving about.</p>
<figure>
<img src="https://figshare.com/ndownloader/files/8066051/preview/8066051/preview.gif" width="100%">
<figcaption>A time-lapse of severe coastal erosion at Narrabeen-Collaroy Beach (SE Australia) during the June 2016 East Coast Low.<br>Source: Mitchell Harley (author provided)</figcaption>
</figure>
<p>By capturing the three-dimensional seabed changes for each event, we could quantify for the first time the precise sand volumes mobilised during these extreme storms.</p>
<p>To give an indication of the scale of beach change, the amount of sand added to the beach resulting from the stormy periods was on the order of 100 cubic metres for every metre length of beach – that’s like 20 tip trucks pouring sand on every metre-wide strip.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-seas-are-coming-for-us-in-kiribati-will-australia-rehome-us-172137">The seas are coming for us in Kiribati. Will Australia rehome us?</a>
</strong>
</em>
</p>
<hr>
<p>As the beaches spanned several kilometres, this amounted to 130,000 cubic metres for La Mision beach, 400,000 cubic metres for Narrabeen and 420,000 cubic metres for Perranporth.</p>
<p>The time-lapse video below is of Wamberal Beach during a storm in 2020. While it wasn’t included in our study, it’s another great example of how large storm waves cause abrupt changes to beaches. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/lSjjG9zpqBg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Source: UNSW Water Research Laboratory (author provided)</span></figcaption>
</figure>
<h2>Rethinking coastal erosion</h2>
<p>Exactly how a coastline might change due to sea-level rise is a key question facing coastal managers, as they plan for the escalating impacts of climate change.</p>
<p>The Intergovernmental Panel for Climate Change <a href="https://www.ipcc.ch/report/ar6/wg1/">projects</a> global sea levels to rise up to 76 centimetres by 2100, under a middle-of-the-road emissions scenario where global temperatures rise 2.1-3.5°C. </p>
<p>The response of the coast to sea-level rise has previously been estimated using an approach known as the Bruun rule. This rule states that for a given metre of sea-level rise, the coastline is expected to retreat between around 20m to over 100m, <a href="https://essd.copernicus.org/articles/11/1515/2019/">depending on the steepness of the coast</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462654/original/file-20220512-11-54h9h7.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">UNSW researcher Chris Drummond launching a drone to survey the beach in Sydney.</span>
<span class="attribution"><span class="source">UNSW Research Laboratory</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Using the Bruun rule, global sea-level rise caused by climate change has been <a href="https://www.nature.com/articles/s41558-020-0697-0?from=article_link">projected to</a> result in losing almost half the world’s sandy beaches by 2100. However, <a href="https://www.nature.com/articles/s41558-020-00934-2">not all coastal scientists share this view</a>.</p>
<p>Let there be no doubt: sea-level rise is a tragic consequence of climate change, and it poses an existential threat to many coastal communities, especially for island nations in the Pacific. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=316&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=316&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=316&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=398&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=398&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462652/original/file-20220512-26-gb6u6j.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=398&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mexico’s La Mision beach, on a calm day. In the winter of 2018-2019, research found that storms pushed 130,000 cubic metres of new sand into the beach system.</span>
<span class="attribution"><span class="source">Autonomous University of Baja California</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>What our new research confirms is that the Bruun rule approach is overly simplistic, as it doesn’t take into account <a href="https://www.sciencedirect.com/science/article/pii/S0964569122001557">the many complex local factors</a> about how individual beaches respond to sea-level rise. </p>
<p>This includes the amount of sand stored in deeper water immediately off the coast, and its potential to replenish beaches during extreme weather events.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462635/original/file-20220512-11-kvyhfz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Understanding how sand moves along the coast is critical for better coastal planning.</span>
<span class="attribution"><span class="source">UNSW Water Research Laboratory</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Improving predictions in an uncertain future</h2>
<p>While this research has focused only on three extreme storm sequences, it shows that <a href="https://theconversation.com/why-some-beaches-including-in-queensland-are-getting-bigger-despite-rising-sea-levels-180964">understanding how sediment moves along the coast</a> is fundamental to planning for climate change impacts.</p>
<p>There are two ways we can significantly improve long-term predictions of coastal change in this uncertain future:</p>
<ol>
<li><p><a href="https://www.environment.nsw.gov.au/research-and-publications/our-science-and-research/our-research/water/offshore-mapping">upscaling efforts in mapping the seabed</a> to learn how much sediment is presently stored in the deeper coastal waters </p></li>
<li><p>increasing routine coastal monitoring of the entire nearshore system, from the sand dunes down to deeper waters. This is currently carried out by <a href="https://coastalmonitoring.org/southwest/">UK coastal observatories</a>. </p></li>
</ol>
<p>A greater understanding of sand movements off the coast, combined with computer modelling, can better forecast future shorelines. This will give coastal managers the information needed to make critical long-term planning decisions for communities.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-some-beaches-including-in-queensland-are-getting-bigger-despite-rising-sea-levels-180964">Why some beaches, including in Queensland, are getting bigger despite rising sea levels</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/182039/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mitchell Harley receives funding from the Australian Research Council</span></em></p><p class="fine-print"><em><span>Gerd Masselink receives funding from NERC.</span></em></p>As sea levels rise, this natural form of beach replenishment might be an important factor in offsetting some of the damaging effects of climate change on beaches.Mitchell Harley, Scientia Senior Lecturer, UNSW SydneyGerd Masselink, Professor of Coastal Geomorphology, University of PlymouthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1809642022-05-01T20:06:17Z2022-05-01T20:06:17ZWhy some beaches, including in Queensland, are getting bigger despite rising sea levels<figure><img src="https://images.theconversation.com/files/459610/original/file-20220425-22-rx6v8d.jpg?ixlib=rb-1.1.0&rect=5%2C5%2C1911%2C1072&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Flinders Beach has been growing since the 1950s</span> <span class="attribution"><span class="source">Kevin Welsh</span>, <span class="license">Author provided</span></span></figcaption></figure><p>In a warmer world, rising sea levels could render many coastlines, beaches, and reef islands uninhabitable, or destroy them altogether. <a href="https://theconversation.com/this-is-the-most-sobering-report-card-yet-on-climate-change-and-earths-future-heres-what-you-need-to-know-165395">The 1.09°C Earth has warmed</a> since pre-industrial times has already heightened seas by 20 centimetres. </p>
<p>But curiously, research shows some coastlines <a href="https://theconversation.com/dynamic-atolls-give-hope-that-pacific-islands-can-defy-sea-rise-25436">and even low-lying coral reef islands</a> are actually <em>growing</em> rather than eroding in the face of rising sea levels. This is happening on some beaches in Queensland and New South Wales, along with coastlines in Asia and Africa.</p>
<p>This goes against the general understanding of how climate change impacts the coast and has led to confusion that has been, in part, deliberately sown into public discourse by climate change deniers. So what’s going on?</p>
<p>To examine the phenomenon, we investigated coastal changes using <a href="https://www.sciencedirect.com/science/article/abs/pii/S0169555X22000034">historical aerial photographs</a> and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0924271621002598">satellite records</a>. We found the observed growth of coastlines is largely linked to the “coastal sediment budget” – the amount of sand, rocks and other sediment moving into and out of the beach over time.</p>
<p>Our results show just how dynamic and complex the coast is, <a href="https://www.sciencedirect.com/science/article/pii/S0964569122001557">highlighting a need for greater understanding of local coastal changes</a>, even down to individual beaches, when making coastal management plans. </p>
<h2>Understanding sediment budgets</h2>
<p>To make sense of this phenomenon, we first need to understand sediment budgets. A “positive” sediment budget is when more sand comes to the beach than leaves. A “negative” budget the opposite, when more sand leaves than arrives.</p>
<p>Over time a positive sediment budget drives growth on the coast – and beaches expand further into the ocean.</p>
<p>Sea level rise, on the other hand, erodes sand from the beach and places it elsewhere on the coast. This can lead to a loss of sand from the beach – and the shoreline retreats inland.</p>
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Read more:
<a href="https://theconversation.com/from-enormous-tides-to-millions-of-shells-here-are-6-unique-beaches-for-your-summer-road-trip-169164">From enormous tides to millions of shells, here are 6 unique beaches for your summer road trip</a>
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<p>So if sea levels are rising across the planet, why are some beaches still getting bigger?</p>
<p>The answer is that for growing beaches, the positive sediment budget currently has a greater impact than erosion from sea level rise. In other words, the amount of sand coming to the coast is greater than the amount lost to sea level rise. </p>
<figure class="align-center ">
<img alt="Aerial photo record showing the growing of the coastline in the Gold Coast" src="https://images.theconversation.com/files/459612/original/file-20220425-31363-avqloy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/459612/original/file-20220425-31363-avqloy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=651&fit=crop&dpr=1 600w, https://images.theconversation.com/files/459612/original/file-20220425-31363-avqloy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=651&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/459612/original/file-20220425-31363-avqloy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=651&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/459612/original/file-20220425-31363-avqloy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=818&fit=crop&dpr=1 754w, https://images.theconversation.com/files/459612/original/file-20220425-31363-avqloy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=818&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/459612/original/file-20220425-31363-avqloy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=818&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Beach change at Coolangatta since the 1930s.</span>
<span class="attribution"><span class="source">Author Provided. Background images from QImagery.</span></span>
</figcaption>
</figure>
<h2>Beaches in Queensland</h2>
<p>We investigated change on the coast of Queensland at 15 beaches stretching from north of Cooktown to Coolangatta, using the aerial photograph record from the 1930’s to present. We also investigated shoreline change globally using the satellite record since 1984.</p>
<p>Despite global sea levels rising 20 centimetres over this time, every beach we investigated in Queensland was growing. </p>
<p>When we looked at coastal changes on at a global scale, we found large parts of entire continents, such as Africa and Southeast Asia, were also growing. This suggests that net positive sediment budgets on the coast are common. </p>
<p>It may be explained by two things. In natural settings, extra sand likely arrives from either deeper sediment located on the continental shelf or from rivers. Human intervention, in the form of coastal development, also drives coastal growth.</p>
<figure class="align-center ">
<img alt="Aerial photo record showing the growing of the coastline" src="https://images.theconversation.com/files/459611/original/file-20220425-31363-bm2nvh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/459611/original/file-20220425-31363-bm2nvh.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=507&fit=crop&dpr=1 600w, https://images.theconversation.com/files/459611/original/file-20220425-31363-bm2nvh.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=507&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/459611/original/file-20220425-31363-bm2nvh.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=507&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/459611/original/file-20220425-31363-bm2nvh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=638&fit=crop&dpr=1 754w, https://images.theconversation.com/files/459611/original/file-20220425-31363-bm2nvh.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=638&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/459611/original/file-20220425-31363-bm2nvh.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=638&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Change in Bucasia Beach since the 1950s.</span>
<span class="attribution"><span class="source">Author Provided. Background images from QImagery.</span></span>
</figcaption>
</figure>
<p>In Queensland, for example, Bucasia Beach has grown due to the natural input of sediment over time, likely from a nearby river. Meanwhile, Coolangatta Beach in the Gold Coast has grown due to human intervention that placed additional sand on the beach to mitigate and reverse trends of erosion.</p>
<p>At a global scale, parts of China’s coast have grown due to human development on the coast. Other regions, such as Suriname, South America, have grown due to large or fast rivers transporting enormous quantities of sediment to the coast.</p>
<figure class="align-center ">
<img alt="Coastal loss and gain in China." src="https://images.theconversation.com/files/459613/original/file-20220425-116752-tb908p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/459613/original/file-20220425-116752-tb908p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=294&fit=crop&dpr=1 600w, https://images.theconversation.com/files/459613/original/file-20220425-116752-tb908p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=294&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/459613/original/file-20220425-116752-tb908p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=294&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/459613/original/file-20220425-116752-tb908p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=369&fit=crop&dpr=1 754w, https://images.theconversation.com/files/459613/original/file-20220425-116752-tb908p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=369&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/459613/original/file-20220425-116752-tb908p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=369&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Coastal change in China using the satellite record since 1985.</span>
<span class="attribution"><span class="source">Author Provided. Background image credits: Esri, World Imagery</span></span>
</figcaption>
</figure>
<p>These results show that sediment budgets and human intervention can be much greater drivers of coastal change than a relatively small rise in sea level. </p>
<p>However, this doesn’t mean sea level rise driven erosion isn’t a real risk in the future. Instead, we should ask: what happens when, as forecasted, the rate of sea level rise continues to accelerate?</p>
<h2>What does this mean for the future?</h2>
<p>The <a href="https://www.ipcc.ch/report/ar6/wg1/#SPM">Intergovernmental Panel on Climate Change (IPCC) forecasts</a> sea levels to reach up to 1.01 metres higher (relative to the 1995-2014 level) by 2100 if global emissions continue unabated. </p>
<p>What’s more, sea level rise <a href="https://theconversation.com/this-is-the-most-sobering-report-card-yet-on-climate-change-and-earths-future-heres-what-you-need-to-know-165395">is getting faster</a>. The IPCC found it rose 1.3 millimetres per year during 1901-1971, 1.9mm per year during 1971-2006, and 3.7mm per year during 2006-2018.</p>
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Read more:
<a href="https://theconversation.com/sea-level-rise-has-claimed-five-whole-islands-in-the-pacific-first-scientific-evidence-58511">Sea-level rise has claimed five whole islands in the Pacific: first scientific evidence</a>
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<p>This increase in sea level may drive a loss of sediment to the beach that current positive sediment budgets can no longer offset. This could trigger erosion in beaches presently growing. </p>
<p>So it’s important coastlines presently growing aren’t seen as evidence that sea level rise does not drive coastal erosion. Nor that such coasts are free from future erosion risk. </p>
<p>Even if there’s enough sediment to maintain growth on the coast, hazardous erosion and inundation due to storms and cyclones can still occur. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/460491/original/file-20220429-23-drojpg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Boats at low tide in Bucasia Beach, Queensland.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure>
<p>When we seek to understand and mitigate the future impact of sea level rise on the coast we should also ask: when does coastal erosion become hazardous? </p>
<p>Coastal erosion is, by itself, a natural process and is only a problem when human infrastructure or livelihoods are at risk. </p>
<p>The sediment budget and decisions we make on the coast – where we build, where we intervene, and where we don’t – are just as critical as sea level rise in the future.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-seas-are-coming-for-us-in-kiribati-will-australia-rehome-us-172137">The seas are coming for us in Kiribati. Will Australia rehome us?</a>
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<p>Most of Australia’s coast is undeveloped and the positive sediment budget on many beaches will limit future erosion. </p>
<p>If we continue to leave them alone, the risk of future hazardous erosion under climate change is low. If, however, we place people and infrastructure too close to the shoreline and disrupt coastal sediment budgets, we will increase our future climate risk.</p><img src="https://counter.theconversation.com/content/180964/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Daniel Harris receives funding from the Australian Institute of Marine Science, the Australian Nuclear Science and Technology Organisation, and the Australian and New Zealand International Ocean Discovery Program Consortium.</span></em></p><p class="fine-print"><em><span>Dylan Cowley and Yongjing Mao do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>This goes against the general understanding of how climate change impacts the coast. So what’s going on?Daniel Harris, Senior Lecturer in Geography, The University of QueenslandDylan Cowley, PhD Candidate, The University of QueenslandYongjing Mao, PhD Candidate, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1796032022-03-25T12:21:48Z2022-03-25T12:21:48ZCoastal home buyers are ignoring rising flood risks, despite clear warnings and rising insurance premiums<figure><img src="https://images.theconversation.com/files/453400/original/file-20220321-13-w076bg.PNG?ixlib=rb-1.1.0&rect=0%2C0%2C2220%2C1394&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Apollo Beach, Fla., averages 3 feet above sea level, with many homes directly on the water.</span> <span class="attribution"><a class="source" href="https://earth.google.com/studio/">Google Earth</a></span></figcaption></figure><p>Apollo Beach, Florida, is a maze of canals lined with hundreds of houses perched right near the water’s edge. The whole community, just south of Tampa, is only about 3 feet above sea level, meaning it’s at risk from storm surge as sea levels rise.</p>
<p>Homebuyers along the U.S. coasts can check each property’s flood risk as easily as they check the size of the bedrooms – most coastal real estate listings now <a href="https://theconversation.com/new-flood-maps-show-us-damage-rising-26-in-next-30-years-due-to-climate-change-alone-and-the-inequity-is-stark-175958">include future flood risk details</a> that take climate change into account. In Apollo Beach, for example, many of the properties are at least 9 out of 10 on the flood risk scale.</p>
<p>That knowledge isn’t stopping homebuyers, though.</p>
<p>Waterfront homes are <a href="https://www.redfin.com/city/21199/FL/Apollo-Beach/housing-market">selling within days</a> of going on the market, and the same story is playing out <a href="https://business.fau.edu/newsroom/press-releases/2022/top-overvalued-metro-housing-markets.php">all along the South Florida coast</a> at a time when <a href="https://theconversation.com/what-drives-sea-level-rise-us-report-warns-of-1-foot-rise-within-three-decades-and-more-frequent-flooding-177211">scientific</a> <a href="https://theconversation.com/new-flood-maps-show-us-damage-rising-26-in-next-30-years-due-to-climate-change-alone-and-the-inequity-is-stark-175958">reports</a> <a href="https://theconversation.com/high-tide-flood-risk-is-accelerating-putting-coastal-economies-at-risk-164481">are warning</a> about the rising risks of coastal flooding as the planet warms.</p>
<p>We are professors of <a href="https://scholar.google.com/citations?user=d7a2JDMAAAAJ&hl=en">urban geography</a> and <a href="https://scholar.google.com/citations?user=JKXl2AYAAAAJ&hl=en">American politics</a> who follow the real estate industry. To understand why people are ignoring a risk that could lead to expensive damage and eventually lower their property value, we talked to hundreds of Florida real estate agents about their clients’ motivations and concerns. </p>
<p>Here’s what we learned.</p>
<h2>Nothing pushes buyers to consider long-term risk</h2>
<p>We surveyed 680 licensed Florida Realtors in late 2020. Their <a href="https://doi.org/10.1007/978-3-030-88435-2_1">responses suggest</a> that prospective homebuyers, by and large, are not taking elevation or flood vulnerability into account when searching for new homes, and the availability of detailed flood risk maps has had little or no impact on them.</p>
<p>Part of the problem may be that mortgage lenders and appraisers aren’t accounting for properties’ vulnerability to sea level rise, so homebuyers aren’t immediately feeling the risk in their pocketbooks. Wealthier buyers who don’t need a mortgage <a href="https://money.com/flood-insurance-cost-2021/">aren’t required</a> to purchase flood insurance, and Congress has a <a href="https://doi.org/10.1007/978-3-030-88435-2_1">history of rolling back</a> flood insurance rate increases.</p>
<p>In short, nothing is forcing buyers to consider the long-term risks.</p>
<figure class="align-center ">
<img alt="Homes along a narrow barrier island with docks out into the bay side." src="https://images.theconversation.com/files/453690/original/file-20220322-25-1gxlcy7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/453690/original/file-20220322-25-1gxlcy7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/453690/original/file-20220322-25-1gxlcy7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/453690/original/file-20220322-25-1gxlcy7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/453690/original/file-20220322-25-1gxlcy7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/453690/original/file-20220322-25-1gxlcy7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/453690/original/file-20220322-25-1gxlcy7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Many Florida beachfront homes and communities are at risk from sea level rise and storm surge.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/florida-hutchinson-island-indian-river-ecological-lagoon-news-photo/982645076">Jeffrey Greenberg/Universal Images Group via Getty Images</a></span>
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<p>At the same time, studies are clearly showing how risks translate into costs. One recent paper by scientists who create flood risk maps found that Hillsborough County, Florida, home to Apollo Beach and Tampa, is likely to see a <a href="https://theconversation.com/new-flood-maps-show-us-damage-rising-26-in-next-30-years-due-to-climate-change-alone-and-the-inequity-is-stark-175958">70% increase</a> in annual flood damage by 2050 because of climate change. That’s less than a 30-year mortgage away.</p>
<h2>What real estate agents are hearing</h2>
<p>We reasoned when we <a href="https://doi.org/10.1007/978-3-030-88435-2_1">started the survey in 2020</a> that if some segment of the population was avoiding property at risk of flooding, then demand should decline and prices should fall. Our <a href="https://doi.org/10.1007/978-3-030-32602-9">previous survey in 2018</a>, involving coastal Florida homeowners, had found that Republicans and Democrats alike believed that their future home values would not be affected by rising seas.</p>
<p>To test the theory that the market is largely ignoring flood risk, we asked real estate agents what they saw: To what extent had they observed house prices either falling or not rising as rapidly for properties at risk of flooding? Forty-five percent reported “not at all.” Only 11 of the 680 agents indicated that house prices for properties at risk of flooding were “very frequently” stagnating or falling.</p>
<p>We also asked if they had seen mortgage lenders declining loan applications or increasing charges for loans in flood-prone areas, in the form of points or mortgage insurance, for example. Sixty percent said, “not at all,” and only 7% said “somewhat frequently,” “very frequently” or “all the time.”</p>
<p>The vast majority of agents, almost 70%, said they expect little impact on the property market in the next five to 10 years.</p>
<p>Here’s some of what they said.</p>
<blockquote>
<p>“People are and will still buy in the coastal areas of Florida, and if they are buying, there will be no decrease in value. The largest pool of buyers driving market are retired or soon to be retired people and they have the belief that they will be long gone before there is any impact from climate change. They mainly are buying on emotion and not factoring in the long-term cost of ownership. They are also buying with cash and no mortgage.”</p>
</blockquote>
<p>Even lenders currently have no real incentives to decline mortgage applications for properties at risk from future sea level rise. Federal agencies that purchase conforming mortgages <a href="https://doi.org/10.1007/978-3-030-88435-2_1">do not currently require</a> the collection of information about flood risk or likely sea level rise. If these requirements were to change, then flood risk would be translated into lending decision.</p>
<blockquote>
<p>“Buyers of coastal properties are financially able to be more risk-oblivious and can afford the higher rate for insurance or be self-insured. Sea-level rise is not currently top-of-mind in our local market.”</p>
</blockquote>
<p>Federal flood insurance has been heavily subsidized by U.S. tax dollars for years. In fact, the National Flood Insurance Program owes the U.S. Treasury <a href="https://sgp.fas.org/crs/homesec/R44593.pdf">about $20 billion</a> for expenses exceeding the premiums homeowners pay. As of April 1, 2022, <a href="https://www.fema.gov/flood-insurance/risk-rating">all of its new and renewed flood insurance policies</a> will be subject to a <a href="https://www.fema.gov/flood-insurance/risk-rating%5D(https://www.fema.gov/flood-insurance/risk-rating">new pricing system termed Risk Rating 2.0</a> designed to take risk into account. </p>
<p>But the program <a href="https://www.nytimes.com/2021/03/18/climate/chuck-schumer-fema-flood-insurance.html">faces political pressure from members of Congress</a> to ensure rates do not rise too quickly or get too high. Further, buyers who purchase houses for cash, a relatively large part of the market in South Florida, are not subject to flood insurance requirements.</p>
<blockquote>
<p>“Wealthy people will still be enamored by the idea of living in front of the sea, but they will probably spend a lot of money making the property more resilient to the effects of sea-level rise. This means that maybe the demand for high end properties will not weaken so much.”</p>
</blockquote>
<p>A few agents suggested that wealthy homeowners are taking the risks seriously and plan to invest in structural changes <a href="https://help.floodfactor.com/hc/en-us/articles/360049475913-Consider-elevating-your-home">such as elevating homes</a> that could make their properties safer from sea level rise and storm surge.</p>
<h2>The market isn’t integrating long-term risks</h2>
<p>Because of <a href="https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_CrossChapterPaper2.pdf">rising sea levels and storm risks</a> resulting from climate change, we conclude that many of the houses currently being sold in south Florida will not outlast their 30-year mortgages without damage or expensive adaptations, and that the resale of houses vulnerable to sea level rise is very likely to become <a href="https://doi.org/10.1007/978-3-030-88435-2_1%22%22">increasingly difficult</a>.</p>
<figure class="align-center ">
<img alt="A man stands just inside the glass door of an art gallery with sandbags keeping out ankle-deep water while a shopper wades past." src="https://images.theconversation.com/files/453693/original/file-20220322-30733-chvoxk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/453693/original/file-20220322-30733-chvoxk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=387&fit=crop&dpr=1 600w, https://images.theconversation.com/files/453693/original/file-20220322-30733-chvoxk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=387&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/453693/original/file-20220322-30733-chvoxk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=387&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/453693/original/file-20220322-30733-chvoxk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=487&fit=crop&dpr=1 754w, https://images.theconversation.com/files/453693/original/file-20220322-30733-chvoxk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=487&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/453693/original/file-20220322-30733-chvoxk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=487&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Florida isn’t the only state dealing with coastal flooding. Businesses in Annapolis, Md., face increasingly frequent high tide and storm surge flooding, as do homeowners in parts of Virginia, South Carolina and other states.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/man-walks-past-an-art-shop-through-flood-waters-in-downtown-news-photo/1236206469">Jim Watson/AFP via Getty Images</a></span>
</figcaption>
</figure>
<p>Florida policymakers to date have either ignored the risk or have taken only limited measures to patch weaknesses, sometimes increasing the risks elsewhere. For example, when <a href="https://www.orlandosentinel.com/opinion/os-ed-florida-without-beaches-blame-seawalls-20170925-story.html">sea walls</a> are erected, they can change how sand washes in, increasing erosion in neighboring areas.</p>
<p>Many people believe “the market” will take care of this issue: that homebuyers, recognizing the looming risks, will discount prices on vulnerable properties, eventually reducing their attractiveness and value. But what we heard from Florida real estate agents casts doubt on the assumption that the market has yet integrated this risk.</p>
<p>[<em><a href="https://memberservices.theconversation.com/newsletters/?source=inline-youresmart">Read The Conversation daily by subscribing to our newsletter</a></em>.]</p><img src="https://counter.theconversation.com/content/179603/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>We asked 680 Florida real estate agents what they’re seeing in the market. Here’s what they said.Risa Palm, Professor of Urban Studies and Public Health, Georgia State UniversityToby W. Bolsen, Associate Professor of Political Science, Georgia State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1773852022-02-27T08:32:36Z2022-02-27T08:32:36ZRising sea levels may threaten 70% of Africa’s heritage sites by 2050<figure><img src="https://images.theconversation.com/files/447751/original/file-20220222-13-1tedu3o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Among the most exposed cultural sites are the iconic ruins of Tipasa in Algeria.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The value of heritage has been <a href="https://www.nature.com/articles/s41558-022-01279-8">underestimated</a> in climate policy and sustainable development circles, but heritage is crucial to people’s identity, culture and wellbeing. It is also critical to the sustainability of communities, ecosystems and biodiversity.</p>
<p>We already <a href="https://www.tandfonline.com/doi/full/10.1080/0067270X.2020.1792177">know</a> that climate change is having an impact on African heritage sites. The issue is gaining visibility. The Intergovernmental Panel on Climate Change and other high profile bodies have recently commissioned the first <a href="https://www.ipcc.ch/event/ipcc-icomos-unesco-co-sponsored-meeting-on-culture-heritage-and-climate-science/">white paper</a> on climate risks to heritage globally. The paper is due in July 2022. </p>
<p>But measurable evidence relating to future impacts of climate change on African heritage has been negligible, limited to a handful of <a href="https://www.nature.com/articles/s41558-022-01280-1">studies</a> on the impacts of sea-level rise on North African cultural heritage sites.</p>
<p>This prompted collaboration between an international group of experts to produce some hard data. We are in the fields of climate risk, coastal modelling, coastal engineering, geographic information systems, and the archaeology and heritage of Africa. We modelled the impacts of extreme sea levels and erosion -– including a one-in-100-years event –- on African heritage sites.</p>
<p>The aim of the <a href="https://www.nature.com/articles/s41558-022-01280-1">research</a> was to accurately map the physical extent of African heritage sites using geo-spatial techniques and then overlay these with flood maps. The maps are based on models of extreme sea-level data. The result was an estimate of how exposed heritage sites are to sea-level rise and coastal erosion in the future. </p>
<p>Our research will help heritage managers identify and prioritise key areas for conservation and heritage adaptation to climate change.</p>
<h2>African heritage exposed</h2>
<p>In the study, UNESCO World Heritage Sites and <a href="https://www.ramsar.org/">Ramsar Wetland Sites</a> were included for the entire African continent. Africa is poorly represented on the <a href="https://whc.unesco.org/en/list/">UNESCO World Heritage List</a> so the team also mapped sites on the <a href="https://whc.unesco.org/en/tentativelists/">UNESCO World Heritage Tentative Lists</a>. A total of 284 sites were mapped; 213 natural sites and 71 cultural sites.</p>
<p>Combined flood and erosion models created specifically for the project were then overlaid on the map of African heritage sites. Different future climate scenarios at different time slices were modelled for exposure of sites to flooding and erosion associated with future sea levels.</p>
<p>The results show that 56 sites (20%) are currently at risk from the one-in-100-years event. By 2050 this number will more than triple to 191 even if carbon emissions remain moderate – the scenario that climate scientists have named RCP4.5. The number of sites exposed increases by seven to 198 (70%) under a high emission scenario. This is known as RCP8.5, or business as usual. Though only seven more sites are exposed under this scenario, the degree of exposure for each site increases significantly. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/these-african-world-heritage-sites-are-under-threat-from-climate-change-144140">These African World Heritage Sites are under threat from climate change</a>
</strong>
</em>
</p>
<hr>
<h2>Geographies of exposure to climate change</h2>
<p>Among the most exposed cultural sites are the iconic ruins of <a href="https://whc.unesco.org/en/list/193/">Tipasa</a> (Algeria), the <a href="https://whc.unesco.org/en/tentativelists/189/">North Sinai Archaeological Sites Zone</a> (Egypt), <a href="https://whc.unesco.org/en/list/1359/">Saloum Delta</a> in Senegal and <a href="https://whc.unesco.org/en/list/761/">Kunta Kinteh</a> in The Gambia. Cultural sites like Tipasa support local businesses that rely on the tourism revenue that the site generates. </p>
<p>Natural sites most exposed include <a href="https://rsis.ramsar.org/ris/1301">Marais de la Mekhada</a> (Algeria), <a href="https://rsis.ramsar.org/ris/666">Parc National du Diawling</a> (Mauritania) and <a href="https://www.keybiodiversityareas.org/site/factsheet/6192">Lake Burullus</a> (Egypt). </p>
<p>North and West Africa have the highest number of exposed sites while sites across small island nations are particularly at risk.</p>
<p>Some countries will see all of their coastal heritage exposed to extreme sea levels by the end of the century, regardless of carbon mitigation strategy. Some of these countries are classified as least developed countries on a development assistance <a href="https://www.oecd.org/dac/financing-sustainable-development/development-finance-standards/daclist.htm">list</a> that provides funding. In these countries, heritage sites compete with clean water, education and energy for funding. Funding to conserve heritage sites is often a very low priority.</p>
<p>Countries in this position include Cameroon, the Democratic Republic of Congo (DRC), Djibouti, Western Sahara, Libya, Mozambique, Mauritania and Namibia. Djibouti, the DRC, Mozambique and Mauritania are classed as least developed countries. Cameroon is a low to middle income country, Libya is a conflict zone and Western Sahara is a disputed territory. They have very few resources to reverse climate change impacts on their heritage sites.</p>
<h2>Climate action for African heritage</h2>
<p>How we respond to climate change matters for heritage. If climate change mitigation reduces greenhouse gas emissions from a high to a moderate pathway by 2050, the number of highly exposed heritage sites can be reduced by 25%. Unprecedented investments are needed to monitor the exposure of these sites and work with local communities to mobilise adaptation response strategies.</p>
<p>These findings motivate for commensurate amounts of climate finance to avoid significant losses and damages from climate change to Africa’s heritage. Decolonial approaches across <a href="https://www.nature.com/articles/s41558-022-01279-8">research and practice</a> can also begin to address systemic inequities, recognise the breadth of heritage and strengthen adaptation action in Africa and globally.</p><img src="https://counter.theconversation.com/content/177385/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nicholas P. Simpson receives funding from the UK Government’s Foreign, Commonwealth & Development Office and the International Development Research Centre, Ottawa, Canada (Grant No. 109419 – 001). </span></em></p><p class="fine-print"><em><span>Joanne Clarke, Lena Reimann, and Michalis Vousdoukas do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Hundreds of Africa’s heritage sites are exposed to sea-level rise and coastal erosion in the future.Joanne Clarke, Senior lecturer, University of East AngliaLena Reimann, Postdoctoral Researcher of Water and Climate Risk, Institute for Environmental Studies (IVM), Vrije Universiteit AmsterdamMichalis Vousdoukas, Coastal oceanographer , European Commission's Joint Research CentreNicholas P. Simpson, Postdoctoral Research Fellow, African Climate and Development Initiative, University of Cape Town, University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1666932021-08-27T13:29:09Z2021-08-27T13:29:09ZHow students can use storytelling to bring the dangers of climate change to life<figure><img src="https://images.theconversation.com/files/417790/original/file-20210825-19-1txty13.jpg?ixlib=rb-1.1.0&rect=2%2C0%2C1914%2C1080&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Coastal communities are likely to be hardest hit by climate change.</span> <span class="attribution"><span class="source">Florence Halstead</span>, <span class="license">Author provided</span></span></figcaption></figure><p>With the stark “<a href="https://www.carbonbrief.org/daily-brief/climate-change-ipcc-report-is-code-red-for-humanity">code red</a>” warnings from the world’s climate experts in the most <a href="https://www.ipcc.ch/report/ar6/wg1/">recent report</a> by the Intergovernmental Panel on Climate Change (IPCC) still ringing in our ears, it’s vital to give as many people as possible the tools with which to tackle the climate crisis. And key to this is encouraging climate literacy.</p>
<p><a href="https://www.climate.gov/teaching/essential-principles-climate-literacy/what-climate-science-literacy#:%7E:text=A%20climate%2Dliterate%20person,in%20a%20meaningful%20way%2C%20and">Climate literacy</a> is the ability to identify, understand and explain information associated with climate science. Being climate literate allows individuals to become active participants in the fight against climate change. </p>
<p>Over the past few years, many young people and educators have pushed for the inclusion of climate literacy in <a href="https://www.heraldscotland.com/opinion/19515536.schools-back-climate-crisis-teaching-kids/">national curricula</a>. So what are the best ways in which this can be embedded within already packed school timetables?</p>
<h2>The importance of stories</h2>
<p>True climate literacy must address not only the science of climate change, but also issues of <a href="https://www.climatejust.org.uk/messages/why-does-climate-justice-matter">climate (in)justice</a>, including how climate change affects people and places unevenly and amplifies inequalities within and across nations. </p>
<p>However, at present, much of climate change education is focused on the physical aspects of climate change, often at a <a href="https://journals.sagepub.com/doi/abs/10.1177/0013916511421196">global scale</a>. Many people in developed countries like the UK therefore see climate change happening elsewhere and to other people, with less relevance to their own lives.</p>
<p>This collective psychological distancing means many fail to <a href="https://www.sciencedirect.com/science/article/abs/pii/S2590332221001834">recognise the urgency</a> of the climate crisis. We need to start highlighting the local effects of climate change to ground abstract understanding in reality.</p>
<p>One way to do this is through visual storytelling. Storytelling, often involving drawings and paintings, has been used by human communities to pass on knowledge or tales of caution for at least <a href="https://www.nationalgeographic.org/encyclopedia/storytelling/#:%7E:text=Some%20of%20the%20earliest%20evidence,%2C%20humans%2C%20and%20other%20objects.">30,000 years</a> – as you can see from the cave painting below. </p>
<figure class="align-center ">
<img alt="Red paintings of animals and humans on the wall of a cave" src="https://images.theconversation.com/files/417785/original/file-20210825-27-1b8xpl.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417785/original/file-20210825-27-1b8xpl.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417785/original/file-20210825-27-1b8xpl.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417785/original/file-20210825-27-1b8xpl.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417785/original/file-20210825-27-1b8xpl.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417785/original/file-20210825-27-1b8xpl.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417785/original/file-20210825-27-1b8xpl.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Paintings, in Bhimbetka Cave, central India, demonstrate humans’ ancient impulse to tell stories.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Bhimbetka_Cave_Paintings.jpg">Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>One effect of storytelling is its ability to create <a href="https://www.simplypsychology.org/cognitive-dissonance.html">cognitive dissonance</a>: the mental conflict and discomfort felt when a person’s behaviour does not align with their beliefs. Stories that demonstrate the consequences of not acting eco-consciously – especially if those consequences are shown visually – can be a good way to do this, leading to individuals being more likely to take <a href="https://iopscience.iop.org/article/10.1088/1748-9326/abcd5a">climate action</a> either in their own lives or by confronting corporate activities. </p>
<h2>The Withernsea project</h2>
<p>As part of the <a href="https://www.hull.ac.uk/work-with-us/research/institutes/energy-and-environment-institute/our-work/insecure-%E2%80%93-capturing-intergenerational-narratives-of-coastal-change">INSECURE</a> project, which looks at how young people engage with coastal change, <a href="https://www.hull.ac.uk/work-with-us/more/media-centre/news/2021/impacts-of-coastal-change-told-by-school-children-in-hard-hitting-university-film">our research team</a> at the University of Hull worked with geography teachers at Withernsea High School to develop new ways in which they could explore the local realities of climate change outside of the classroom. <a href="https://www.examinerlive.co.uk/news/local-news/pretty-yorkshire-town-under-threat-21111170">Withernsea</a>, a town in an area known as Holderness on the east coast of England, is home to one of the world’s fastest receding coastlines with an average erosion rate of <a href="https://studyrocket.co.uk/revision/a-level-geography-edexcel/coastal-landscapes-change/holderness#:%7E:text=The%20Holderness%20Coast%20is%20one,around%202%20metres%20per%20year.">two metres</a> per year. </p>
<p>Coastal retreat has in fact been recorded since Roman times, with <a href="https://gmd.copernicus.org/preprints/gmd-2019-197/gmd-2019-197.pdf">over 30 settlements</a> estimated to have been lost to the North Sea in the last 2,000 years. But the rates of retreat are accelerating due to changes in climate activity such as enhanced rainfall and extended periods of drought, and will continue <a href="https://www.sciencedirect.com/science/article/abs/pii/S096456911400074X">to accelerate</a> as sea levels rise, placing already vulnerable communities quite literally on the edge. </p>
<figure class="align-center ">
<img alt="A coastline, edged by houses, showing signs of erosion" src="https://images.theconversation.com/files/417781/original/file-20210825-17-10auqp9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417781/original/file-20210825-17-10auqp9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417781/original/file-20210825-17-10auqp9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417781/original/file-20210825-17-10auqp9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417781/original/file-20210825-17-10auqp9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417781/original/file-20210825-17-10auqp9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417781/original/file-20210825-17-10auqp9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The clearly visible coastal erosion at Holderness endangers the communities who live there.</span>
<span class="attribution"><span class="source">Florence Halstead</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The Holderness coast is a key <a href="https://www.internetgeography.net/topics/the-holderness-coast-case-study/">case study</a> in England’s geography curriculum, with the science behind its eroding coastline taught to thousands of schoolchildren across the country. However, the teachers we worked with remarked that lessons are typically focused on the physical processes of coastal erosion within a very restricted narrative, avoiding considerations of social impacts. Our sessions attempted to make the issue more relevant to young people’s lives by engaging them with the effects coastal change will have on their community. </p>
<h2>What the students did</h2>
<p>As part of our sessions, students aged 12 to 14 years old interviewed members of their community to ask them how coastal change has affected them during their lifetime. Students then chose how they wanted to tell their interviewees’ stories, employing a range of creative methods.</p>
<p>These included transferring the stories into poems or photo montages that represented both the interviewee’s story and the student’s perspective, intertwining the two generations’ narratives. Many community members kindly offered their own songs, poems, photos and footage. The moving collection of stories was then turned into a film to capture these narratives of coastal change that sit at the heart of the Withernsea community. </p>
<p><a href="https://www.youtube.com/watch?v=dV6z0LKobfE&ab_channel=Energy%26EnvironmentInstitute%2CUniversityofHull">The film</a> records a bleak version of events and details how loss, desolation and fear has struck many students and interviewees as they have begun to engage with the impact climate change will have on their community. We intend to carry on our work with the students to explore hopeful narratives relating to climate adaptation and community resilience that also came to light within the project.</p>
<figure class="align-center ">
<img alt="An aerial view of a barge carrying rocks" src="https://images.theconversation.com/files/418019/original/file-20210826-13-u69jbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418019/original/file-20210826-13-u69jbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418019/original/file-20210826-13-u69jbu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418019/original/file-20210826-13-u69jbu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418019/original/file-20210826-13-u69jbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418019/original/file-20210826-13-u69jbu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418019/original/file-20210826-13-u69jbu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">One of the many barges bringing rocks from Norway to enhance coastal protection in Withernsea.</span>
<span class="attribution"><span class="source">Florence Halstead</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Since completing this project, we’ve noticed Withernsea’s young people are more motivated to take action. One commented “there needs to be more stuff done about climate change”, adding “I hope to be able to stay here, live here and to work around here and not have to move away”. </p>
<p>The next stages of our research will reflect how a separated community has come together through this journey towards climate literacy, and explore how best to put young people at the front and centre of local climate solutions.</p><img src="https://counter.theconversation.com/content/166693/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Katie Parsons receives funding from University of Hull, Natural England, Natural Environmental Research Council, Wellcome Trust, Ferens Trust, Ernest Cook Trust, The British Society for Geomorphology and the Environment Agency.</span></em></p><p class="fine-print"><em><span>Lisa Jones’ research is funded by the British Academy’s Youth Futures Programme, supported under the UK Government's Global Challenges Research Fund.</span></em></p><p class="fine-print"><em><span>Florence Halstead does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>In a region threatened by coastal erosion, a group of school students learned how they could explore change using visual stories and poems.Dr Katie Parsons, Research Assistant and PhD Researcher in Energy and Environment, University of HullFlorence Halstead, Social Researcher, University of HullLisa Jones, Senior Lecturer in Education, University of HullLicensed as Creative Commons – attribution, no derivatives.