tag:theconversation.com,2011:/us/topics/weather-satellites-19570/articlesWeather satellites – The Conversation2023-03-14T12:24:44Ztag:theconversation.com,2011:article/1981402023-03-14T12:24:44Z2023-03-14T12:24:44ZHow to use free satellite data to monitor natural disasters and environmental changes<figure><img src="https://images.theconversation.com/files/514756/original/file-20230310-14-ffq8d1.jpg?ixlib=rb-1.1.0&rect=851%2C251%2C1541%2C1099&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Over 8,000 satellites are orbiting Earth today, capturing images like this, of the Louisiana coast.</span> <span class="attribution"><a class="source" href="https://earthobservatory.nasa.gov/world-of-change/WaxLake">NASA Earth Observatory</a></span></figcaption></figure><p>If you want to track changes in the Amazon rainforest, see the full expanse of a hurricane or figure out where people need help after a disaster, it’s much easier to do with the view from a satellite orbiting a <a href="https://aerospace.csis.org/aerospace101/earth-orbit-101">few hundred miles above Earth</a>.</p>
<p>Traditionally, access to satellite data has been limited to researchers and professionals with expertise in remote sensing and image processing. However, the increasing availability of open-access data from government satellites such as <a href="https://landsat.gsfc.nasa.gov/">Landsat</a> and <a href="https://sentinels.copernicus.eu/">Sentinel</a>, and free cloud-computing resources such as <a href="https://aws.amazon.com/earth/">Amazon Web Services</a>, <a href="https://earthengine.google.com/">Google Earth Engine</a> and <a href="https://planetarycomputer.microsoft.com/">Microsoft Planetary Computer</a>, have made it possible for just about anyone to gain insight into environmental changes underway. </p>
<p>I <a href="https://wetlands.io/">work with geospatial big data</a> as a professor. Here’s a quick tour of where you can find satellite images, plus some free, fairly simple tools that anyone can use to create time-lapse animations from satellite images.</p>
<p>For example, state and urban planners – or people considering a new home – can watch over time <a href="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif">how rivers have moved</a>, construction crept into wildland areas or <a href="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif">a coastline eroded</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A squiggly river moves surprisingly quickly over time." src="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=352&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=352&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=352&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=442&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=442&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=442&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Landsat time-lapse animations show the river dynamics in Pucallpa, Peru.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NASA Landsat</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Animation shows the shoreline shrinking." src="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=349&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=349&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=349&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=439&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=439&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=439&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 Landsat time-lapse shows the shoreline retreat in the Parc Natural del Delta, Spain.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NASA Landsat</span></span>
</figcaption>
</figure>
<p>Environmental groups can monitor deforestation, the effects of climate change on ecosystems, and how other human activities like irrigation are <a href="https://images.theconversation.com/files/508817/original/file-20230208-23-o026h9.gif">shrinking bodies of water</a> like <a href="https://earthobservatory.nasa.gov/world-of-change/AralSea">Central Asia’s Aral Sea</a>. And disaster managers, aid groups, scientists and anyone interested can monitor natural disasters such as <a href="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif">volcanic eruptions</a> and <a href="https://images.theconversation.com/files/508822/original/file-20230208-14-3xtadg.gif">wildfires</a>.</p>
<figure class="align-center ">
<img alt="The lake, created by damming the river, has shrunk over time." src="https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=367&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=367&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=367&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=461&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=461&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=461&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">GOES images show the decline of the crucial Colorado River reservoir Lake Mead since the 1980s and the growth of neighboring Las Vegas.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NOAA GOES</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A volcanic eruption bursts into view." src="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=352&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=352&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=352&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=442&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=442&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=442&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 GOES satellite time-lapse shows the Hunga Tonga volcanic eruption on Jan. 15, 2022.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NOAA GOES</span></span>
</figcaption>
</figure>
<h2>Putting Landsat and Sentinel to work</h2>
<p>There are over <a href="https://www.geospatialworld.net/prime/business-and-industry-trends/how-many-satellites-orbiting-earth">8,000 satellites orbiting the Earth</a> today. You can see a live map of them at <a href="https://www.keeptrack.space/">keeptrack.space</a>.</p>
<p>Some transmit and receive radio signals for communications. Others provide global positioning system (GPS) services for navigation. The ones we’re interested in are Earth observation satellites, which collect images of the Earth, day and night.</p>
<p><strong>Landsat:</strong> The longest-running Earth satellite mission, <a href="https://landsat.gsfc.nasa.gov/">Landsat</a>, has been collecting imagery of the Earth since 1972. The latest satellite in the series, <a href="https://www.usgs.gov/landsat-missions/landsat-9">Landsat 9</a>, was launched by NASA in September 2021.</p>
<p>In general, Landsat satellite data has a spatial resolution of about 100 feet (about 30 meters). If you think of pixels on a zoomed-in photo, each pixel would be 100 feet by 100 feet. Landsat has a temporal resolution of 16 days, meaning the same location on Earth is imaged approximately once every 16 days. With both Landsat 8 and 9 in orbit, we can get a global coverage of the Earth <a href="https://www.mdpi.com/1424-8220/20/22/6631">once every eight days</a>. That makes comparisons easier.</p>
<p><a href="https://www.usgs.gov/landsat-missions/landsat-data-access">Landsat data</a> has been freely available to the public since 2008. During the <a href="https://en.wikipedia.org/wiki/2022_Pakistan_floods">Pakistan flood of 2022</a>, scientists used Landsat data and free cloud-computing resources to determine the flood extent and <a href="https://share.gishub.org/pakistan_floods/">estimated the total flooded area</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Images show how the flood covered about a third of Pakistan." src="https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=489&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=489&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=489&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Landsat satellite images showing a side-by-side comparison of southern Pakistan in August 2021 (one year before the floods) and August 2022 (right)</span>
<span class="attribution"><span class="source">Qiusheng Wu, NASA Landsat</span></span>
</figcaption>
</figure>
<p><strong>Sentinel:</strong> <a href="https://sentinels.copernicus.eu/">Sentinel</a> Earth observation satellites were launched by the European Space Agency (ESA) as part of the <a href="https://www.copernicus.eu/en">Copernicus program</a>. Sentinel-2 satellites have been collecting optical imagery of the Earth since 2015 at a spatial resolution of 10 meters (33 feet) and a temporal resolution of 10 days.</p>
<p><strong>GOES:</strong> The images you’ll see most often in U.S. weather forecasting come from NOAA’s Geostationary Operational Environmental Satellites, or <a href="https://www.goes.noaa.gov/">GOES</a>. They orbit above the equator at the <a href="https://www.nesdis.noaa.gov/current-satellite-missions/currently-flying/geostationary-satellites">same speed Earth rotates</a>, so they can provide continuous monitoring of Earth’s atmosphere and surface, giving detailed information on weather, climate, and other environmental conditions. <a href="https://www.goes-r.gov/multimedia/dataAndImageryImagesGoes-16.html">GOES-16</a> and <a href="https://www.goes-r.gov/multimedia/dataAndImageryImagesGoes-17.html">GOES-17</a> can image the Earth at a spatial resolution of about 1.2 miles (2 kilometers) and a temporal resolution of five to 10 minutes.</p>
<figure class="align-center ">
<img alt="Animation showing swirling clouds off the coast and the long river of moisture headed for California." src="https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=353&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=353&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=353&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=444&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=444&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=444&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A GOES satellite shows an atmospheric river arriving on the West Coast in 2021.</span>
<span class="attribution"><span class="source">Qiusheng Wu, GOES</span></span>
</figcaption>
</figure>
<h2>How to create your own visualizations</h2>
<p>In the past, creating a Landsat time-lapse animation of a specific area required extensive data processing skills and several hours or even days of work. However, nowadays, free and user-friendly programs are available to enable anyone to create animations with just a few clicks in an internet browser.</p>
<p>For instance, I created an <a href="https://huggingface.co/spaces/giswqs/Streamlit">interactive web app</a> for my students that anyone can use to generate time-lapse animations quickly. The user zooms in on the map to find an area of interest, then draws a rectangle around the area to save it as a GeoJSON file – a file that contains the geographic coordinates of the chosen region. Then the user uploads the GeoJSON file to the web app, chooses the satellite to view from and the dates and submits it. It takes the app about 60 seconds to then produce a time-lapse animation.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/VVRK_-dEjR4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How to create satellite time-lapse animations.</span></figcaption>
</figure>
<p>There are several other useful tools for easily creating satellite animations. Others to try include <a href="https://jdbcode.github.io/Snazzy-EE-TS-GIF/">Snazzy-EE-TS-GIF</a>, an Earth Engine App for creating Landsat animations, and <a href="https://planetarycomputer.microsoft.com/docs/overview/explorer/">Planetary Computer Explorer</a>, an explorer for searching and visualizing satellite imagery interactively.</p><img src="https://counter.theconversation.com/content/198140/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Qiusheng Wu receives funding from NASA. He is an Amazon Visiting Academic and a Google Developer Export (GDE) for Earth Engine. </span></em></p>Time-lapse animations that once took days to create are now easy to build with publicly available satellite images and free online tools.Qiusheng Wu, Assistant Professor of Geography and Sustainability, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1032032018-09-13T18:33:03Z2018-09-13T18:33:03ZWhy hurricane forecasters can’t ‘politicize’ storm warnings even if they wanted to<figure><img src="https://images.theconversation.com/files/236264/original/file-20180913-177941-19y3123.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Rising tides move closer to the dunes in Kill Devil Hills, N.C., Sept. 13, 2018, as Hurricane Florence approaches the east coast. </span> <span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Tropical-Weather-North-Carolina/7a37ea4ca5c942789bd6284342502318/17/0">AP Photo/Gerry Broome</a></span></figcaption></figure><p><a href="http://geography.uga.edu/directory/people/j-marshall-shepherd">Dr. Marshall Shepherd</a> of the University of Georgia famously talks about <a href="https://www.forbes.com/sites/marshallshepherd/2017/03/24/20-common-myths-that-climate-scientists-often-hear/#7fb3903d5acb">“climate zombie myths”</a>: No matter how many times you slay them, they keep coming back. </p>
<p>In 2016 conservative news blogger Matt Drudge <a href="http://www.npr.org/2016/10/07/496996886/matt-drudge-suggests-government-may-be-lying-about-hurricane-matthew">accused</a> the federal government of hyping the threat as Hurricane Matthew approached the U.S. coast, purportedly to play up possible links between extreme weather and climate change. <a href="https://theconversation.com/weather-forecasters-cant-manipulate-hurricane-warnings-heres-why-66937">I explained</a> how this not only was false, but that it would be impossible for the National Hurricane Center to manipulate hurricane forecasts in a political manner, given that all the raw information is accessible to anyone today with an internet connection.</p>
<p>Apparently, Rush Limbaugh did not read the article, for he has made <a href="https://www.newsweek.com/rush-limbaugh-says-hurricane-florence-forecast-trying-heighten-belief-climate-1117416">very similar claims</a> regarding <a href="https://www.weather.gov/wrn/florence">forecasts for Hurricane Florence</a>. A simple reading of warnings and key messages from the <a href="https://www.nhc.noaa.gov/">National Hurricane Center</a> (NHC) shows a very different reality. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=382&fit=crop&dpr=1 600w, https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=382&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=382&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=481&fit=crop&dpr=1 754w, https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=481&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/236265/original/file-20180913-177965-1fqe6i7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=481&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Senior Hurricane Specialist Stacy Stewart watches monitors at the National Hurricane Center, Sept. 4, 2018, in Miami.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Tropical-Weather/3e17c16c5c984e95bd481937f2698409/12/0">AP Photo/Wilfredo Lee</a></span>
</figcaption>
</figure>
<h2>Accuracy, not hype</h2>
<p>Anyone living in the Carolinas should take this storm extremely seriously. Florence will produce a large and dangerous storm surge. It is a very large hurricane, like <a href="https://www.weather.gov/mob/katrina">Hurricane Katrina</a> in 2005. It is slow-moving, like <a href="https://www.nhc.noaa.gov/data/tcr/AL092017_Harvey.pdf">Hurricane Harvey</a> in 2017, and will drop prodigious amounts of rain on the Southeast. The <a href="https://www.nhc.noaa.gov/refresh/graphics_at1+shtml/093018.shtml?key_messages#contents">National Hurricane Center’s “Key Messages”</a> cogently summarize these life-threatening hazards.</p>
<p>Nonetheless, U.S. government forecasters <a href="https://www.usatoday.com/story/news/nation/2018/09/12/hurricane-florence-track-turns-south-expected-slow-carolinas/1276645002/">downgraded Florence from Category 3 to Category 2</a> as it approached the coast on Sept. 12. They did so because observations from satellites, aircraft and ocean buoys showed the storm was a Category 2 hurricane – no more, no less.</p>
<p>Moreover, it would be virtually impossible for our government, or any weather service, to intentionally overhype or downplay the real risks of a major hurricane as it approaches the United States. </p>
<p>I have been involved with operational weather forecasting for nearly 40 years. From 2005 through 2009, I was responsible for typhoon forecasts that the Defense Department’s <a href="http://www.metoc.navy.mil/jtwc/jtwc.html">Joint Typhoon Warning Center</a> issued for the western Pacific and Indian oceans. After retiring from the Navy, I served as chief operating officer for the <a href="http://www.noaa.gov/">National Oceanic and Atmospheric Administration</a>. In this position, I was responsible for the <a href="http://www.weather.gov/">National Weather Service</a> and its components, including the <a href="http://www.nhc.noaa.gov/">National Hurricane Center</a>.</p>
<p>During my career I have seen the internet and social media transform weather forecasting in general, and hurricane forecasting in particular, from a skill that was seen and practiced by a small community of specialists into one of the most transparent technical endeavors we do on a routine basis. Every forecaster I have ever worked with – military or civilian – wants to get predictions right. And even if they wanted to shade the forecast one way or another to support some agenda, it would be impossible to do it in today’s networked world.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1038503246766252032"}"></div></p>
<h2>The weather community opens up</h2>
<p>In the pre-internet era, hurricane forecasting was more of an art than a science. Modern weather forecasting developed in the 1960s with the advent of <a href="http://earthobservatory.nasa.gov/Features/WxForecasting/wx4.php">radar, computers and satellites</a>. Well into the 1980s, forecasters were still working out how best to integrate satellite data into computer-based forecasts. Satellite measurements and computing power were crude by today’s standards. </p>
<p>Observations and computer prediction models traveled on government-only, proprietary circuits, with only limited access by private forecasters or academia. Government forecasters would share storm track and intensity forecasts with the public, along with short written discussions (TRANSMITTED IN ALL CAPS), but little else. Processes for deriving forecasts were closely held, available only to members of a very select and specialized guild. Private-sector forecasting of hurricanes was in its infancy, hampered by a lack of real-time information.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/weoWlAs4Dr4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A high definition camera outside the International Space Station captured a view of Hurricane Florence at 7:50 a.m. EDT on Sept. 12.</span></figcaption>
</figure>
<p>Starting in the 1990s, personal computers, dial-up access and then the internet fundamentally changed the way weather information could be accessed and distributed. Today global weather models from the United States, Canada, United Kingdom and the European Centre for Medium Range Weather Forecasting are available to anyone with an internet connection. When the NHC directs U.S. Air Force Reserve personnel or NOAA “Hurricane Hunters” to fly a hurricane reconnaissance mission, <a href="http://tropicalatlantic.com/recon/">the data they collect</a> are posted virtually in real time. Satellite images from the JTWC or NHC forecast are available online free of charge. </p>
<p>For hurricanes, the federal government produces one official forecast from either the National Hurricane Center for the eastern Pacific and Atlantic oceans or the Joint Typhoon Warning Center for the western Pacific and Indian oceans. This forecast draws on computer-based weather forecast models, an assessment of the storm’s real-time characteristics, and the knowledge of a highly trained typhoon duty officer or hurricane specialist. It would be obvious instantaneously if it deviated substantially from observed conditions, or from a blend of the computerized forecast guidance, without providing some meteorological or physical explanation.</p>
<p>This level of transparency is fairly new. As recently as the early 2000s, there were significant and sometimes emotional debates within the weather forecasting community over how much computer modeling data and information from weather observations should be publicly available in real time. Some forecasters worried, and still do now, that users could misinterpret individual pieces of data or second-guess official forecasts. Over time, however, consensus has grown in favor of making all the data available to anyone interested, so that everyone can see how forecasts are put together. </p>
<h2>Forecasting hurricanes in the internet era</h2>
<p>Now that so much weather data is publicly available, the explosion of social media guarantees that thousands of observers are looking over forecasters’ shoulders. And forecasts get a lot of attention, especially when they involve extreme events.</p>
<p>Hundreds of people with varying credentials comment on every tropical storm, hurricane or cluster of thunderstorms. Popular sites like <a href="https://www.wunderground.com/">Weather Underground</a> and <a href="https://www.windytv.com/?45.151,-9.668,4">Windy</a> further attest to broad public interest in all things meteorological.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/141525/original/image-20161012-16246-1l1ff08.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/141525/original/image-20161012-16246-1l1ff08.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=801&fit=crop&dpr=1 600w, https://images.theconversation.com/files/141525/original/image-20161012-16246-1l1ff08.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=801&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/141525/original/image-20161012-16246-1l1ff08.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=801&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/141525/original/image-20161012-16246-1l1ff08.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1007&fit=crop&dpr=1 754w, https://images.theconversation.com/files/141525/original/image-20161012-16246-1l1ff08.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1007&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/141525/original/image-20161012-16246-1l1ff08.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1007&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Poster from Weather Underground.</span>
<span class="attribution"><a class="source" href="https://www.wunderground.com/weather-posters/">Weather Underground</a></span>
</figcaption>
</figure>
<p>If U.S. government forecasters appeared to be disregarding either observations or reliable forecast models without explanation, weather enthusiasts would quickly point this out on social media, and major news media would pick up the story. We don’t see this in headlines because it doesn’t happen. </p>
<p>Weather forecasters understand that they walk on a knife’s edge between over-warning on the one hand – which can produce false alarms and complacency – and under-warning on the other, potentially trapping people in life-threatening situations. The National Hurricane Center, backed by a national and international network of observers, scientists and computer models, does amazing work under very high pressure. There always are lessons to be learned, but the bottom line is that we owe them thanks, and Mr. Limbaugh owes them an apology.</p>
<p><em>This is an updated version of an <a href="https://theconversation.com/weather-forecasters-cant-manipulate-hurricane-warnings-heres-why-66937">article</a> originally published on October 12, 2016.</em></p><img src="https://counter.theconversation.com/content/103203/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Titley is an advisory board member of National Academy of Sciences Board on Atmospheric Science and Climate and Citizens' Climate Lobby. He is a Board member of the Council for Strategic Risks, is affiliated with the Hoover Institution's Arctic Security Initiative, and currently chairs the National Academy of Sciences Climate Communications Initiative.</span></em></p>Don’t believe the skeptics or the conspiracy theorists: Weather forecasters can’t slant hurricane warnings to make political points.David Titley, Professor of Practice in Meteorology, Professor of International Affairs & Director Center for Solutions to Weather and Climate Risk, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/942722018-04-05T10:44:33Z2018-04-05T10:44:33ZLook up – it’s a satellite!<figure><img src="https://images.theconversation.com/files/213249/original/file-20180404-189816-1rj8a2b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The ISS sees us on Earth, but look up at night and you may see it, too.</span> <span class="attribution"><a class="source" href="https://www.nasa.gov/multimedia/imagegallery/image_feature_390.html">NASA </a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>I saw my first artificial satellite with my naked eyes during the summer of 1994. I was watching pieces of comet Shoemaker-Levy 9 impact Jupiter from a small observatory with a college astronomy club when someone pointed up – away from the telescope – and said, “Look, it’s a satellite!”</p>
<p>Before then, I had never really thought much about whether or not satellites were visible without a telescope or binoculars. They are fun to spot, though, so ever since then, I point them out whenever I am at the telescopes for a public observing event. I often use the <a href="http://heavens-above.com">Heavens Above</a> astronomy site or the <a href="http://starrynight.com/Enthusiast7/index.html">Starry Night</a> app to check on satellites that catch my attention.</p>
<p>And you can too. On any given night, if it is dark and with little moonlight, you can easily see several satellites – launched to orbit Earth for various purposes.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/213247/original/file-20180404-189804-1g3m25j.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">Some satellites – including Landsat 8 – send back images of Earth.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/content/landsat-8s-first-year">NASA/David Roy</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Hardware in the heavens</h2>
<p>It’s tricky to get a good estimate for how many satellites are in the skies above us because many are classified or were launched by countries that don’t openly share the details of their launches. The Union of Concerned Scientists maintains a <a href="https://www.ucsusa.org/nuclear-weapons/space-weapons/satellite-database#.WsKPKtPwZp8">searchable database of satellites</a>, which lists more than 1,700 in orbit right now, while <a href="http://heavens-above.com">Heavens Above</a> lists <a href="http://www.heavens-above.com/Satellites.aspx?lat=0&lng=0&loc=Unspecified&alt=0&tz=UCT">about the same number</a> (although it includes some that burned up years ago). Some sources suggest there could be several thousand more than that currently in the skies.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=776&fit=crop&dpr=1 600w, https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=776&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=776&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=976&fit=crop&dpr=1 754w, https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=976&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/213286/original/file-20180404-95689-1kam13d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=976&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Neil Gehrels in the cleanroom with the Swift telescope while under construction.</span>
<span class="attribution"><a class="source" href="https://asd.gsfc.nasa.gov/Neil.Gehrels/photos/">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Countries and companies launch satellites for lots of reasons; many are designed and built for the purpose of doing astronomy. For example, my colleagues work with the NASA Goddard Space Flight Center to operate the <a href="https://swift.gsfc.nasa.gov">Neil Gehrels Swift Observatory</a>, which orbits the Earth at 600 kilometers using telescopes to detect high-energy light, including ultraviolet, X-rays and gamma rays.</p>
<p>Besides these kinds of astrophysics missions, there are communications satellites, satellites that make up the GPS network, satellites that study the Earth (such as weather satellites), and those launched by the military for defense purposes, such as taking images of sensitive nuclear sites.</p>
<p>They all transmit their data down to ground stations using radio signals, which can be collected every time the satellite passes over the station. A typical satellite, like Swift, takes only about 90 minutes to go all the way around the Earth once, so it has multiple opportunities to transfer data every day.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/213253/original/file-20180404-189795-1rtltvp.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">An Iridium flare in the night sky.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/vanessapatea/11168351056">Vanessa Patea</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>What you can see</h2>
<p>Only some satellites are large enough, reflective enough, and on low enough orbits to be seen by the naked eye, but on a good night I have seen between five and 10 of them in a few hours of watching. A typical satellite can be visible for several minutes. You can follow one by eye, as it tracks across a long path across the sky. </p>
<p>The International Space Station is one of the most spectacular – it can look brighter than most stars. “<a href="http://www.skyandtelescope.com/observing/celestial-objects-to-watch/observing-iridium-flares/">Iridium flares</a>” also stand out; they occur when one of the many commercial communications satellites launched by the company <a href="https://www.iridium.com/network/iridium-next/">Iridium</a> is at the right part of its orbit for the shiniest part of its surface to reflect sunlight to your location. These Iridium flares can go from invisible to the naked eye, to brighter than the planet Venus, and back again, in less than a minute. People who aren’t familiar with their predictable behavior often mistake them for UFOs. </p>
<p>Modern satellites are designed to allow operators to direct them to re-enter Earth’s atmosphere in a controlled manner and completely incinerate. Every year, though, some satellites make an <a href="http://www.aerospace.org/cords/research/reentry-data/">“uncontrolled” re-entry</a>. This is what happened with Chinese satellite Tiangong 1 in 2018. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=423&fit=crop&dpr=1 754w, https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=423&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/213289/original/file-20180404-189804-1ywd4qm.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=423&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Apps like Starry Night can guide you through what you’re seeing in the sky, including satellites. This was the view from Penn State in the early morning of Dec. 21, 2016.</span>
<span class="attribution"><span class="source">Starry Night screenshot</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>A couple years back, at a public observing event, we spotted a really bright satellite, brighter than most planets. Using reference resources, I was able to verify that we were seeing Tiangong 1. It had originally been part of China’s program to build a space station, though no humans have been on board for several years. Eventually the <a href="http://www.skyandtelescope.com/astronomy-news/tiangong-1-remote-reentry/">satellite lost the ability to communicate</a> <a href="https://www.space.com/27320-tiangong-1.html">with the ground</a>, so there was no easy way to command it to fire its engines to either raise it to a higher orbit or direct it into a controlled descent.</p>
<p>Tiangong 1 slowly, but unpredictably, began to spiral in closer to the Earth. It eventually mostly burned up in the atmosphere – but because of its large size, some pieces likely <a href="http://www.aerospace.org/cords/reentry-predictions/tiangong-1-reentry/">splashed into the southern Pacific Ocean</a> around 8:15 p.m. EDT, on April 1, 2018.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/213255/original/file-20180404-189824-vpqsfs.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 long exposure captures an Iridium flare, which looks like a horizontal streak in middle of this image.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/kevlar/14056867322">Kevin Baird</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Given that Earth has so much uninhabited area, no one has ever been hit by space debris. So the next time you’re stargazing, don’t worry about the infinitesimal risk that a satellite will fall down to where you are – just enjoy the view of these human-made objects orbiting above us in space.</p><img src="https://counter.theconversation.com/content/94272/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Palma 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>A couple thousand satellites are orbiting Earth right now. Under the right conditions, your naked eye can spot these human-made objects in the night sky.Christopher Palma, Associate Teaching Professor and Associate Department Head for Undergraduate Programs in Astronomy & Astrophysics, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/866772017-11-21T19:28:36Z2017-11-21T19:28:36ZWe’re drafting a legal guide to war in space. Hopefully we’ll never need to use it<figure><img src="https://images.theconversation.com/files/195152/original/file-20171117-14665-15q9ymq.jpg?ixlib=rb-1.1.0&rect=1562%2C709%2C1221%2C1172&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Nothing to stop high energy weapons being deployed in orbit around Earth.</span> <span class="attribution"><span class="source">Marc Ward/Shutterstock</span></span></figcaption></figure><p>A <a href="http://edition.cnn.com/videos/tv/2016/11/23/exp-cnn-special-report-war-in-space.cnn">war in outer space</a> sounds like the stuff of <a href="https://breakingdefense.com/2016/12/stop-the-fearmongering-over-war-in-space-the-skys-not-falling-part-1/">science fiction</a> but it is something we <a href="https://thediplomat.com/2017/01/how-china-is-weaponizing-outer-space/">need to consider</a>.</p>
<p>Its <a href="http://docs.house.gov/meetings/AS/AS29/20170329/105785/HHRG-115-AS29-Wstate-SheltonW-20170329.pdf">impact</a> on everybody on Earth and its implications for future human space exploration would be devastating.</p>
<p>Right now, there are <a href="http://ndupress.ndu.edu/JFQ/Joint-Force-Quarterly-87/Article/1325996/the-role-of-space-norms-in-protection-and-defense/">laws</a> that are relevant to the prospect of war in space, but currently it is unclear exactly how these might be applied. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/step-up-australia-we-need-a-traffic-cop-in-space-86464">Step up Australia, we need a traffic cop in space</a>
</strong>
</em>
</p>
<hr>
<p>We and our colleagues from around the world – including experts from Australia, Canada, the United States, Russia and China – are undertaking a multi-year project to provide a definitive guide on how law applies to military uses of outer space.</p>
<p>The aim is to develop a Manual on International Law Applicable to Military uses of Outer Space (<a href="http://www.mcgill.ca/milamos/">MILAMOS</a>) that covers times of tension and outright hostility.</p>
<p>The ultimate <a href="http://digitool.library.mcgill.ca/webclient/StreamGate?folder_id=0&dvs=1510027493698%7E784">goal</a> is to help build transparency and confidence between space-faring states. </p>
<p>This should reduce the possibility of a war in space, or if it does happen, reduce the impact on the <a href="http://www.ucsusa.org/nuclear-weapons/space-weapons/what-are-satellites-used-for#.WgEFtLZ7FE4">space infrastructure</a> that we have all come to rely on so heavily.</p>
<h2>The satellites we rely on</h2>
<p>We rely on GPS signals for many things, including navigation, communication, banking, agriculture, travel and the internet itself. It’s <a href="http://europa.eu/rapid/press-release_IP-11-398_en.htm?locale=en">estimated</a> that 6-7% of GDP in Western countries depends on satellite navigation. </p>
<p>Communications satellites are applied not just for direct broadcast television, but also to enable many terrestrial networks. In remote areas of the world, they may be the only means of communication. </p>
<p>In the near future, communications satellites could provide the <a href="https://theconversation.com/a-new-space-race-is-on-to-bring-the-internet-to-the-whole-world-29028">whole world with broadband internet</a>.</p>
<p>Satellites help us get weather forecasts and improve agricultural production. They also help us to plan disaster relief, find and mine natural resources, monitor the health of the environment and many other applications.</p>
<h2>‘Expect’ war in space</h2>
<p>In the military context too, satellites have become essential. In June this year, US Secretary of the Air Force <a href="http://www.af.mil/News/Article-Display/Article/1224907/air-force-leaders-continue-to-emphasize-air-and-space-priorities-on-capitol-hill/">Heather Wilson said</a> a future war in space is likely and the US is investing heavily in maintaining its military dominance in space. She commented:</p>
<blockquote>
<p>We must expect that war, of any kind, will extend into space in any future conflict, and we have to change the way we think and prepare for that eventuality.</p>
</blockquote>
<p>The first Gulf War in 1991 has often been called the first space war, though it wasn’t actually fought in outer space. Rather, the US and coalition forces <a href="https://www.scientificamerican.com/article/gps-and-the-world-s-first-space-war/">relied heavily on GPS</a> and other satellite technology to conduct that conflict.</p>
<p>Since then, space-based assets have enabled even greater capability for land, sea and air forces.</p>
<p>Given the <a href="https://link.springer.com/referenceworkentry/10.1007/978-1-4614-6423-5_107-1">dual use</a> of many satellites, an <a href="https://prezi.com/oreiegimwxig/star-laws-why-the-law-of-armed-conflict-matters-in-outer-space/">armed conflict in space</a> could be catastrophic to modern life.</p>
<h2>Treaty on some weapons in space</h2>
<p>There are only five global <a href="http://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties.html">treaties</a> specific to space. Chief among them is the <a href="http://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/outerspacetreaty.html">1967 Outer Space Treaty</a>, but only one of its provisions (Article IV) directly deals with military activity – it prohibits the placement of weapons of mass destruction in space.</p>
<p>Other means and methods of <a href="https://thediplomat.com/2015/10/should-the-us-fear-chinas-new-space-weapons/">destroying or interfering</a> with a satellite are <a href="https://link.springer.com/chapter/10.1007/978-90-6704-933-7_8">not prohibited</a>, although other areas of law, like the Laws of Armed Conflict, regulate their use.</p>
<p>This includes things such as anti-satellite missiles, directed energy weapons (including lasers), electronic warfare, cyber warfare and dual-use technology, such as on-orbit servicing (“mechanic”) satellites.</p>
<h2>A combined effort</h2>
<p>The MILAMOS project is <a href="http://www.mcgill.ca/milamos/participating-institutions">led by three universities</a>: Adelaide here in Australia, McGill in Canada, and Exeter in the UK. It received some funding from the Australian and Canadian governments, as well as from private donors. </p>
<p>It relies on expertise from the International Committee of the Red Cross, the Union of Concerned Scientists and from the major space-faring states, principally the US and Russia, but also China and other countries.</p>
<p>They participate in a strictly personal (rather than representative) capacity to provide an authentic account of what the law is, not to negotiate what states would like the law to be. </p>
<p>Even so, reflecting a true consensus position on the law, in spite of the strongly held personal positions of individual experts, can be challenging. But that is what the project aims to achieve in nine workshops over three years. </p>
<p>So far meetings have been held in <a href="https://www.mcgill.ca/milamos/progress#MILAMOS%20Inaugural%20Plenary">Montreal</a>, <a href="https://blogs.adelaide.edu.au/law/2017/03/07/first-major-milamos-workshop-held-at-adelaide-law-school/">Adelaide</a>, <a href="https://idsa.in/speech/milamos-jayant-prasad-2017">New Delhi</a> and <a href="http://www.usafa.af.mil/News/Article-Display/Article/1341927/conference-could-have-huge-ramifications-for-space-experts-say/">Colorado Springs</a> in the US.</p>
<h2>Mind the legal gap</h2>
<p>The alternate is for states to formally negotiate <a href="https://www.un.org/press/en/2016/gadis3557.doc.htm">new international instruments</a> to clarify or extend the law. Unfortunately, recent attempts to do so have <a href="http://www.unoosa.org/pdf/SLW2016/Opening/3._Meyer_-_SpaceCoopUNOOSASep52016.pdf">not met with great success</a>. This creates a legal gap that this manual seeks to fill.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/star-wars-turns-40-and-it-still-inspires-our-real-life-space-junkies-78094">Star Wars turns 40 and it still inspires our real life space junkies</a>
</strong>
</em>
</p>
<hr>
<p>In this regard, it is similar to other manuals drafted in recent years on the law applicable to warfare in other domains: maritime (<a href="https://ihl-databases.icrc.org/ihl/INTRO/560?OpenDocument">San Remo Manual</a>), air and missile (<a href="https://www.cambridge.org/core/books/hpcr-manual-on-international-law-applicable-to-air-and-missile-warfare/EB28F7A1701637CA2390B25FB4840629">Harvard Manual</a>) and cyber (<a href="https://ccdcoe.org/tallinn-manual.html">Tallinn Manual</a>).</p>
<p>Even though these manuals are not formally endorsed by states, they are an <a href="https://drmc.library.adelaide.edu.au/dspace/handle/2440/97930">essential reference</a> for those who work in the field. This includes military practitioners, government lawyers and policy advisors, the media, public advocacy groups and other non-government organisations.</p>
<p>Final publication of the manual is expected in 2020. Paradoxically, the MILAMOS contributors earnestly hope that the manual will only ever remain on the shelf and never be used.</p><img src="https://counter.theconversation.com/content/86677/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Prof Dale Stephens works for The University of Adelaide and is the Editor in Chief of the MILAMOS Project. </span></em></p><p class="fine-print"><em><span>Duncan Blake is Deputy Editor-in-Chief of the MILAMOS Project, and a PhD student at the University of Adelaide, supervised by Prof Dale Stephens (the Editor-in-Chief). The Project has received government funding in Canada and Australia, and private funding from a variety of sources (<a href="http://www.mcgill.ca/milamos/about#SUPPORT">http://www.mcgill.ca/milamos/about#SUPPORT</a>).</span></em></p>Australia is playing a major role in developing legal guidelines that would govern how any war in space is played out. The authors of MILAMOS hope the manual is never actually required.Dale Stephens, Professor of Law, University of AdelaideDuncan Blake, PhD candidate, law and military uses of outer space, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/850172017-10-03T14:48:01Z2017-10-03T14:48:01ZSixty years after Sputnik: taking stock and looking to the future<figure><img src="https://images.theconversation.com/files/188362/original/file-20171002-3124-17qxe3m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A girl takes a close look at the world's first artificial
satellite, the Soviet-made Sputnik I.</span> <span class="attribution"><span class="source">China Photos/Reuters</span></span></figcaption></figure><p>It’s been 60 years since the Soviet Union fired the first salvo of the space age. On October 4 1957 it launched <a href="https://www.nasa.gov/multimedia/imagegallery/image_feature_924.html">Sputnik</a>, the world’s first satellite, as its contribution to <a href="http://www.nas.edu/history/igy/">International Geophysical Year</a>.</p>
<p>It was the first of a series of superpower spectaculars, each bringing <a href="https://www.jstor.org/stable/1148580?seq=1#page_scan_tab_contents">soft power</a> – the term political scientists use to describe states doing something benign which boosts their prestige. The USSR followed Sputnik’s launch by sending <a href="https://www.space.com/16159-first-man-in-space.html">Yuri Gagarin</a>, the world’s first cosmonaut, into space on 12 April 1961. He was followed by <a href="https://starchild.gsfc.nasa.gov/docs/StarChild/whos_who_level2/tereshkova.html">Valentina Tereshkova</a>, the first woman to orbit the Earth, on 16 June 1963. The US landed 12 Americans on the moon between 1969 and 1972.</p>
<p>A great deal has changed in the past 60 years. Sputnik <a href="https://www.space.com/17563-sputnik.html">weighed 83kgs</a>. The <a href="https://www.nasa.gov/mission_pages/station/main/index.html">International Space Station</a> weighs 419 tons, carrying a crew of six astronauts, performing a variety of experiments in microgravity. Many countries have their own <a href="http://adsabs.harvard.edu/full/1990MNSSA..49..174G">space policies</a> and space science has developed all over the world including <a href="http://www.sajs.co.za/sites/default/files/publications/pdf/Ngcofe%20-%20commentary_DOI.pdf">in Africa</a>.</p>
<p>Our fascination with space – whether it focuses on colonising distant planets, using satellites for profit or educational purposes, or unpacking complex weather patterns – shows no signs of slowing down.</p>
<h2>Many uses for satellites</h2>
<p>Today satellite applications are woven into the fabric of everyday life. </p>
<p>Soon after Sputnik’s launch, the military realised that spacecraft would be great for reconnaissance – <a href="https://www.airspacemag.com/space/spysats-for-everyone-299492/">spysats</a>. These are now commonplace.</p>
<p>Satellites have offered great benefits for ordinary people, too. Civilians now depend on spacecraft to get <a href="https://www.eumetsat.int/website/home/index.html">weather forecasts</a>. </p>
<p>Satellites have also changed how we see the world around us, quite literally. The corporate world entered space when <a href="https://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1964-047A">Syncom 3</a> caused a sensation with its live broadcasts of the 1964 Tokyo Olympics. Before that, your grandparents waited three weeks for newsreels to be flown to Hollywood to have the film developed, duplicated, then flown to cinemas around the world.</p>
<p>Digital processing of images and other data now constitute the most lucrative ground segment of the space industry; that is, jobs on the ground, not in orbit. The information from this processing also helps with disaster recovery: authorities can ascertain the extent of hurricane, flood or fire damage; they can also see where roads are blocked by mudslides.</p>
<p>Satellite farming is another valuable tool. It comprises satellites which send SMSes to subscribers alerting them to which orchards are too dry and any that are too wet, so they may adjust their irrigation. And satellites allow us to peer back into the distant past. Archaeologists have used satellite imagery to locate <a href="https://ideas.ted.com/gallery-archaeological-mysteries-hidden-in-satellite-images/">ancient towns</a> buried beneath sand dunes and tropical forests. </p>
<h2>Developing countries</h2>
<p>Some developing countries have also harnessed the power of satellites. India led the way in demonstrating a space programme relevant to developing countries. Its <a href="http://www.isro.gov.in/category-spacecraft/edusat">EDUSAT</a> broadcasts televised maths lessons to more than 11 000 rural schools and colleges across the country. Under-qualified teachers are able to learn alongside their schoolchildren. </p>
<p>It would be good for South Africa – and other African countries with poor science and maths results – to put its most charismatic teachers in those subjects in front of TV cameras, and stream them into classrooms across a country. </p>
<p>African countries could adopt another Indian satellite initiative, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2782224/">telemedicine</a>. Using video conferencing, a nurse examines a patient under a specialist’s guidance, enabling her to diagnose, and prescribe medicine.</p>
<p>South Africa was an early adopter of satellite vehicle tracking, to combat hijacking. Today two pan African television companies, DSTV and Multichoice, are big business. The South African space industry employs several hundred people. Most manufacture satellite components for export from the Western Cape towns of Somerset West and Stellenbosch. </p>
<p>Others staff the huge Hartebeespoort ground station, downloading and uploading; under contract to foreign space agencies and aerospace corporations. This falls under the <a href="http://www.sansa.org.za/">South African National Space Agency</a>.</p>
<p>Another space agency facility is the Space Weather Centre in Hermanus, in the Western Cape province. Its scientists monitor changes in the Earth’s magnetic field caused by solar flares and solar storms. Violent fluctuations can blow up transformers in sub-stations, and damage power utility Eskom’s grid.</p>
<p>Stellenbosch University electronic engineering students built South Africa’s first satellite, <a href="https://directory.eoportal.org/web/eoportal/satellite-missions/s/sunsat">Sunsat</a>, launched in 1999. Their spinoff company, Sunspace, built the country’s second satellite, Sumbandila. Students from the Cape Peninsula University of Technology were responsible for developing the third satellite, the cubesat <a href="https://theconversation.com/cool-cubes-are-changing-the-way-we-play-in-space-41621">Tshepiso</a>. South Africa’s first satellite was launched by the US and the other two by the Russians.</p>
<p>Algeria, Egypt, Ghana, and Nigeria are among other African countries who have paid space powers to launch one or more satellites for them. South Africa negotiated the <a href="http://adsabs.harvard.edu/full/2008AfrSk..12...53M">African Resources Monitoring Constellation</a>, for each to share data with the others.</p>
<h2>What of the future?</h2>
<p>There’s much more to come.</p>
<p>Elon Musk’s <a href="https://www.scientificamerican.com/article/elon-musk-publishes-plans-for-colonizing-mars/">proposals</a> to build a town the size of Oudtshoorn (a small city in South Africa) on Mars every 26 months have grabbed the headlines.</p>
<p>Without headlines and much fanfare, meanwhile, one <a href="http://www.aesihyd.com/hypersonic_conference/contents/Proceeding_June_2007.pdf">Indian research programme</a> completed the number-crunching, concept calculations for a spaceplane which could take off and land on runways, but also reach orbit. They named it Hyperplane, with a smaller technology demonstrator called Avatar. </p>
<p>Hyperplane would make an ideal project to be partnered by countries in either the IBSA (India-Brazil-South Africa) or BRICS (Brazil, Russia, India, China, South Africa) alliances.</p>
<p>South Africa has niche aerospace capabilities in avionics, hi-tech composite materials, and sensors. The <a href="http://www.denelotr.co.za/">Overberg Test Range</a>, with its embedded Air Force Test Flight Development Centre, is ideal for the test programme of what would be 25 and 100 ton drones.</p>
<p>Brazil’s <a href="http://embraer.com/">Embraer</a>, the world’s third largest aircraft manufacturer, can clearly be drawn in, while Russia, India, and China have all the research and development capabilities needed. Brazil, India, and China can also provide all the capital needed.</p>
<p>Now it’s over to farsighted diplomats and those on the relevant parliamentary committees to revive and complete this Indian project – and give Elon Musk a run for his money.</p><img src="https://counter.theconversation.com/content/85017/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Keith Gottschalk serves on the executive of the SA Space Association, but writes this article in his individual capacity.</span></em></p>Our fascination with space shows no signs of slowing down, 60 years after the Soviet Union launched the world’s first satellite, Sputnik.Keith Gottschalk, Political Scientist, University of the Western CapeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/697052016-12-01T01:56:53Z2016-12-01T01:56:53ZEyes in the sky: Cutting NASA Earth observations would be a costly mistake<figure><img src="https://images.theconversation.com/files/148168/original/image-20161130-17040-m6n6nw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">NASA Earth Science Division operating missions, including systems managed by NOAA and USGS</span> <span class="attribution"><a class="source" href="https://eospso.nasa.gov/">NASA Earth Observing System</a></span></figcaption></figure><p>Donald Trump’s election is generating much speculation about how his administration may or may not reshape the federal government. On space issues, a senior Trump advisor, former Pennsylvania Rep. Bob Walker, has called for ending NASA earth science research, including work related to climate change. Walker contends that NASA’s proper role is deep-space research and exploration, not <a href="https://www.theguardian.com/environment/2016/nov/22/nasa-earth-donald-trump-eliminate-climate-change-research">“politically correct environmental monitoring.”</a> </p>
<p>This proposal has caused <a href="https://theconversation.com/five-reasons-why-cutting-nasas-climate-research-would-be-a-colossal-mistake-69336">deep concern</a> for many in the climate science community, including people who work directly for NASA and others who rely heavily on NASA-produced data for their research. Elections have consequences, and it is an executive branch prerogative to set priorities and propose budgets for federal agencies. However, President-elect Trump and his team should think very carefully before they recommend canceling or defunding any of NASA’s current Earth-observing missions. </p>
<p>We can measure the Earth as an entire system only from space. It’s not perfect – you often need to look through clouds and the atmosphere – but there is no substitute for monitoring the planet from pole to pole over land and water. These data are vital to maintaining our economy, ensuring our safety both at home and abroad, and quite literally being an “eye in the sky” that gives us early warning of changes to come. To paraphrase Milton Friedman, there’s no free lunch. If NASA is not funded to support these missions, additional dollars will need to flow into NOAA and other agencies to fill the gap. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/148197/original/image-20161201-17815-10v8v07.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/148197/original/image-20161201-17815-10v8v07.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/148197/original/image-20161201-17815-10v8v07.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/148197/original/image-20161201-17815-10v8v07.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/148197/original/image-20161201-17815-10v8v07.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/148197/original/image-20161201-17815-10v8v07.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/148197/original/image-20161201-17815-10v8v07.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">NASA satellite data show the spread of hemlock decline, caused by an invasive insect called the hemlock woolly adelgid, near North Carolina’s Mount Mitchell in February 2016. Brown areas have less vegetation than normal for the time of year.</span>
<span class="attribution"><a class="source" href="http://earthobservatory.nasa.gov/IOTD/view.php?id=89083">NASA Earth Observatory</a></span>
</figcaption>
</figure>
<h2>Shared missions</h2>
<p>The <a href="http://history.nasa.gov/spaceact.html">National Aeronautics and Space Act of 1958</a>, which created NASA, explicitly listed “the expansion of human knowledge of phenomena in the atmosphere and space” as one of the new agency’s prime objectives. Other federal agencies have overlapping missions, which is normal, since there are few neatly defined stovepipes in the real world. The <a href="http://www.noaa.gov/about-our-agency">National Oceanic and Atmospheric Administration</a>, which is part of the Department of Commerce, works to “understand and predict changes in climate, weather, oceans, and coasts.” And the <a href="http://govinfo.library.unt.edu/npr/library/status/mission/musgs.htm">U.S. Geological Survey</a>, a bureau of the Interior Department, is charged with “characterizing and understanding complex Earth and biological systems.” </p>
<p>These primary earth science agencies have a pretty clear division of labor. NOAA and USGS fund and operate a constellation of weather- and land-observing satellites, while NASA develops, prototypes and flies higher-risk, cutting-edge science missions. When these technologies have been proven, and Congress funds them, NASA transfers them to the other two agencies. </p>
<p>For example, in the NOAA-NASA partnership to develop the next generation of operational <a href="http://www.jpss.noaa.gov/">weather-observing satellites</a>, NASA took the lead in prototyping and reducing risk by building the <a href="https://www.nasa.gov/mission_pages/NPP/main/index.html">Suomi NPP satellite</a>. That satellite, now five years old, is improving our daily weather forecasts by sending terabytes of data every day to supercomputers at NOAA. Its images also help with tasks as diverse as <a href="http://www.jpss.noaa.gov/news_stories/news_86.html">navigating in the Arctic</a> through the Northwest Passage and <a href="http://cimss.ssec.wisc.edu/goes/blog/archives/22720">monitoring the tragic wildfires</a> near Gatlinburg, Tennessee. The experience NASA gained by developing the new technologies is now incorporated into NOAA’s <a href="http://www.jpss.noaa.gov/launch_schedule.html">Joint Polar Satellite System</a>, whose first launch is scheduled for next year.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/148202/original/image-20161201-16399-omstuy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/148202/original/image-20161201-16399-omstuy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=369&fit=crop&dpr=1 600w, https://images.theconversation.com/files/148202/original/image-20161201-16399-omstuy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=369&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/148202/original/image-20161201-16399-omstuy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=369&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/148202/original/image-20161201-16399-omstuy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=464&fit=crop&dpr=1 754w, https://images.theconversation.com/files/148202/original/image-20161201-16399-omstuy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=464&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/148202/original/image-20161201-16399-omstuy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=464&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">In an image from the Suomi NPP satellite, Hurricanes Madeline and Lester, both hovering between Categories 3 and 4, bear down on Hawaii on Aug. 29, 2016.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/image-feature/hurricanes-madeline-and-lester">NASA Earth Observatory</a></span>
</figcaption>
</figure>
<p>When I served as NOAA’s chief operating officer, I met regularly with my NASA counterpart to ensure that we were not duplicating efforts. Sometimes these relationships are even more complex. As oceanographer of the Navy, I worked with NOAA, NASA and the government of France to ensure joint funding and mission continuity for the <a href="https://www.nesdis.noaa.gov/jason-3/">JASON-3 ocean surface altimeter system</a>. The JASON satellites measure the height of the ocean’s surface, track sea level rise and help the National Weather Service (which sits within NOAA) forecast tropical cyclones that threaten U.S. coastlines.</p>
<p>It is vital for these agencies to coordinate, but each plays an important individual role, and they all need funding. NOAA does not have enough resources to build and operate a number of NASA’s long-term space-based Earth observing missions. For its part, NASA focuses on new techniques and innovations, but is not funded to maintain legacy operational spacecraft while simultaneously pushing the envelope by developing new technologies. </p>
<h2>The value of space observation</h2>
<p>To many members of the earth science community, organizational issues between NASA and NOAA are secondary to the real problem: lack of sufficient and sustained funding. NASA and NOAA are working jointly to patch together a space-based Earth observing system, but do not receive sufficient resources to fully meet the mission. </p>
<p>An administration that truly wanted to improve this situation could do so by developing a comprehensive Earth observing strategy and asking Congress for enough money to execute it. That would include maintaining NASA’s annual Earth science budget at around US$2 billion and increasing NOAA’s annual satellite budget by $1-2 billion. </p>
<p>There’s a reason why space is called “the ultimate high ground” and our country spends billions of dollars each year on space-based assets to support our national intelligence community. In addition to national security, NASA missions contribute vital information to many other users, including <a href="https://www.nasa.gov/feature/goddard/satellite-based-flood-monitoring-central-to-relief-agencies-disaster-response">emergency managers and the Federal Emergency Management Agency (FEMA)</a>, <a href="https://newfarmers.usda.gov/usda-and-nasa-explore-frontier-agriculture">farmers</a>, <a href="http://appliedsciences.nasa.gov/system/files/docs/AGU2013_Poster.pdf">fishermen</a> and <a href="https://www.nasa.gov/feature/goddard/2016/satellite-data-could-help-reduce-flights-sidelined-by-volcanic-ash">the aviation industry</a>. </p>
<p>While NASA’s Earth observation satellites support numerous research scientists in government labs and <a href="https://www.washingtonpost.com/news/capital-weather-gang/wp/2015/05/01/cutting-nasas-earth-science-budget-is-short-sighted-and-a-threat/?utm_term=.4c3df77f2900">universities</a>, they also provide constant real-time data on the state of space weather, the atmosphere and the oceans – information that is critical to U.S. Navy and Department of Defense operations worldwide. </p>
<p>Six years ago while I was serving as oceanographer of the Navy, I was asked to estimate how much more money the Navy would need to spend if we did not have our NASA and NOAA partners. The answer was, very conservatively, $2 billion per year just to maintain the capability that we had. That figure has almost certainly increased. If the Trump administration cuts NASA’s earth science funding, that capability will need to come from some other set of agencies. Has the new team thought seriously about which agencies should have their budgets increased to make up this gap? </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/148169/original/image-20161130-17770-mupzv0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/148169/original/image-20161130-17770-mupzv0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/148169/original/image-20161130-17770-mupzv0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/148169/original/image-20161130-17770-mupzv0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/148169/original/image-20161130-17770-mupzv0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/148169/original/image-20161130-17770-mupzv0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/148169/original/image-20161130-17770-mupzv0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Sea surface temperatures, October 2016, based on NASA satellite data. Sea surface temperatures affect weather, including hurricanes, and animal and plant life in the oceans.</span>
<span class="attribution"><a class="source" href="http://neo.sci.gsfc.nasa.gov/view.php?datasetId=MYD28M">NASA Earth Observations</a></span>
</figcaption>
</figure>
<p>Finally a few thoughts about the elephant in the room: climate change. Mr. Walker has said that “<a href="https://www.theguardian.com/environment/2016/nov/22/nasa-earth-donald-trump-eliminate-climate-change-research">we need good science to tell us what the reality is</a>,” a statement virtually everyone would agree with. The way to have good science is to fund a sustained observation system and ensure the scientific community has free and full access to the data that these satellites produce. </p>
<p>Not funding observation systems, or restricting access to their data, will not change the facts on the ground. Ice will continue to melt, and our atmosphere and oceans will continue to warm. Such a policy would greatly increase risks to our economy, and even to many Americans’ lives. In the business world, this stance would be considered gross negligence. In government <a href="https://theconversation.com/a-military-view-on-climate-change-its-eroding-our-national-security-and-we-should-prepare-for-it-65535">the stakes are even higher</a>.</p><img src="https://counter.theconversation.com/content/69705/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Titley is a member of the CNA Military Advisory Board, He is an advisory board member of Citizens' Climate Lobby the Bulletin of the Atomic Scientists, and the Center for Climate and Security. Titley receives no funding from NASA or any other federal agency.</span></em></p>President Trump’s 2018 budget request cuts funding for NASA Earth observation research and cancels four missions. Weather forecasters, businesses, scientists and the armed forces rely on this data.David Titley, Professor of Practice in Meteorology, Professor of International Affairs & Director Center for Solutions to Weather and Climate Risk, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/561612016-06-12T17:42:58Z2016-06-12T17:42:58ZNovel use of satellite data is helping Africa cope with natural disasters<figure><img src="https://images.theconversation.com/files/125342/original/image-20160606-26003-1w29fm9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Fields showing little signs of plant emergence at a late stage of the season, indicating a near total crop loss in Zimbabwe.</span> <span class="attribution"><span class="source">Chris Funk</span></span></figcaption></figure><p>When we were kids, watching the Earth from space was fun: weather satellite images were eye candy displayed on the evening news. Today the data from these satellites help create the first line of defence for the <a href="https://www.elninooxfam.org/">60 million people</a> suffering food insecurity due to the recent massive El Niño. </p>
<p>In Ethiopia and southern Africa millions of people face terrible food shortages. These were successfully anticipated using our new satellite-gauge rainfall data. Our Climate Hazards Group’s Infrared Precipitation with Stations (<a href="http://chg.geog.ucsb.edu/data/chirps/index.html">CHIRPS</a>) system was also successfully used soon after its February 2015 release by the <a href="http://www.fews.net/">Famine Early Warning Systems Networks</a> and the <a href="https://www.wfp.org/content/seasonal-monitor">World Food Programme</a> to identify large rainfall deficits and poor maize production in Haiti and Central America, where some 3.5 million people face food insecurity.</p>
<p>We have mixed emotions about this success: we are glad that our information can help identify food-insecure populations before disaster strikes, but dismayed that such populations exist at all. Like the inventor of a better fire hose, we hate to see CHIRPS in use for drought early warning, but this is the reason we <a href="http://www.nature.com/articles/sdata201566">developed it</a>.</p>
<h2>The historical record</h2>
<p>The CHIRPS is a gridded rainfall time series that brings together high-resolution <a href="http://www.earth-syst-sci-data.net/7/275/2015/essd-7-275-2015-discussion.html">average rainfall</a> data gleaned from satellites and weather station data to provide a comprehensive picture of rainfall patterns from 1981 to the near-present. Alone, the <a href="http://www.nature.com/articles/sdata201566">dataset</a> can be used to assess droughts over a 35-year period. Together with longer station-based datasets like the 1900-2014 <a href="http://www.nature.com/articles/sdata201550">Centennial Trends</a> archive it can be used to assess droughts over 50 or 60 years. This allows us to identify rainfall declines and specify precisely how bad a bad season is. </p>
<p>For example, data from CHIRPS, combined with the Centennial Trends archive, shows that northern Ethiopia is facing its <a href="http://www.fews.net/sites/default/files/documents/reports/FEWS%20NET_Ethiopia%202015%20Drought%20Map%20Book_20151217_0.pdf">worst drought</a> in 50 years. Figure 1 shows a time series we produced to document the severity of the Ethiopian drought. We call this kind of figure a “science haiku”. It is years, if not decades, of effort boiled down into a simple info-graphic that we hope will motivate action.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=336&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=336&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=336&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=423&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=423&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125341/original/image-20160606-25985-w6l1er.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=423&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Figure 1: The
severity of the Ethiopia drought.</span>
<span class="attribution"><span class="source">Chris Funk</span></span>
</figcaption>
</figure>
<p>Such graphics can also be spatial. In the case of southern Africa, rainfall for much of the region from October to February has been extremely poor. This widespread dryness is having a dramatic effect on <a href="http://www.fews.net/southern-africa/alert/february-2016">food production</a>, with sown fields showing barely a hint of emergence at a late stage of the season. As a result, maize production in Zimbabwe may be as little as one-quarter of the recent average.</p>
<p>For early warning of such droughts, it is necessary to gather data on rainfall and rainfall variation. If conditions that are drier than normal are considered against a historical backdrop, the severity of the rainfall deficit can be quickly evaluated. This, in turn, could inform drought responses. </p>
<h2>Gathering data</h2>
<p>Since the 1960s we have observed clouds from satellites in space. NASA’s <a href="http://science.nasa.gov/missions/tiros/">Television Infrared Satellite</a> was one of the first. By 1962 the NASA programme was providing continuous coverage of Earth.</p>
<p>The satellites housed two infrared television cameras that recorded the brightness of infrared radiation emitted from the Earth’s surface or clouds. These images left two profound legacies: a better understanding of our dynamic Earth; and a better means of tracking severe droughts.</p>
<p>To understand how the satellites work, we need to consider the relationship between the temperatures of an object and the intensity of the emitted radiation – or “light”, in the case of visible radiation. Two important aspects of electromagnetic radiation are:</p>
<ul>
<li><p>The warmer an object gets, the more radiation it releases; and</p></li>
<li><p>The warmer an object is, the higher the frequency of its emitted radiation.</p></li>
</ul>
<p>The amount of energy emitted by an object increases dramatically as the temperature goes up. This allows us to discriminate, in satellite imagery, between cold clouds and the warm surface of the Earth. As seen from space, infrared images record dark cold clouds and warm bright emissions from Earth’s surface. When we see satellite images on the evening news these are typically reversed.</p>
<p>While everything on Earth emits electromagnetic radiation, the type of radiation is determined by its wavelength. This is a function of the object’s temperature: at the coldest end of the scale, the near vacuum of empty space emits radio waves; at the hottest extreme objects such as pulsars or the edges of black holes emit x-ray or cosmic ray radiation.</p>
<p>In measuring radiation, we are able to get a sense of temperature. Warmer places emit much more radiation than cold places. High-level clouds, for example, are much colder (about -40°C) than the surface of the Earth (about 15°C). By tracking how temperatures in the satellite images flicker between passing cold cloud tops and the warmer surface of the Earth, we can estimate the “cold cloud duration” of each day – the fraction of time that the satellite sees very cold cloud tops.</p>
<p>The radiation that is recorded by satellites and transmitted to Earth also provides an indication of precipitation. Very high clouds – particularly in the tropics – indicate deep convection, which could indicate precipitation. While a lot can go wrong with these estimates they perform reasonably well in many tropical and sub-tropical regions.</p>
<p>What geostationary satellites are particularly good at is seeing droughts. While seeing a lot of cold cloud tops may indicate that it is raining a lot, not seeing any cold cloud tops means it is definitely not raining. So if you know when and where to look – like in the middle of the grain filling period in a food-insecure place – and day in and day out you only see the hot surface of the Earth, you can be pretty sure of trouble. </p>
<p>We are able to blend this trove of vital information with data from a large number of station observations. We are then able to calculate anomalies between the satellite rainfall estimates and those of station observations. Where we have station observations, we can use these to nudge the satellite estimates closer to the truth. But where we don’t, we revert to satellite observations combined with high-resolution climatology.</p>
<h2>A ‘monster’ El Niño</h2>
<p>A 35-year dataset allows us to better place current conditions in historical context.</p>
<p>The current Ethiopian and southern African crises are linked to the recent monster El Niño. El Niño sea surface temperature anomalies between December 2015 and February 2016 were much warmer than at any time in the historical record. The increase of 2.2°C was also much warmer than those of the recent massive El Niños in 1997/98 and 1982/83 (both an increase of 1.6°C). </p>
<p>This time series also displays a long-term warming trend, and a much greater frequency of strong (+0.8°C) El Niños. Since 1980, these have occurred once every four years. This is a rapid increase compared with the period from 1855 to 1979, when they occurred once every 14 years. </p>
<p>If extreme El Niño and La Niña events are becoming more common, the CHIRPS and Centennial Trends data sets will help us respond to these extremes.</p><img src="https://counter.theconversation.com/content/56161/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Funk receives funding from the Famine Early Warning Systems Network (FEWS NET), the United States Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA). Dr. Funk is an employee of the USGS.</span></em></p><p class="fine-print"><em><span>Greg Husak receives funding from the Famine Early Warning Systems Network (FEWS NET), the United States Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA). </span></em></p>Satellite rainfall data can be used to predict harsh climate events – and to identify food-insecure populations before disaster strikes.Chris Funk, Affiliated Research Professor, Department of Geography and Research Director, Climate Hazards Group, University of California, Santa BarbaraGreg Husak, Assistant Researcher, Rainfall Monitoring, Applied Statistics, Famine Early Warning, University of California, Santa BarbaraLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/445942015-08-18T20:33:41Z2015-08-18T20:33:41ZWeather forecasting is about to get even better<p>While some people might still joke about the reliability of weather forecasts, meteorologists are likely to nominate weather prediction as one of the great success stories of modern science – a crowning achievement of collaboration across many scientific and technological fields.</p>
<p>And now Australian weather forecasts are about to become even better, thanks to a new satellite and supercomputer.</p>
<p>Most of us simply take it for granted that weather can be forecast with some accuracy several days ahead. As measured by maximum and minimum temperature predictions for the next day, over 95% of forecasts issued by the Australian Bureau of Meteorology are verified as accurate to within 3 degrees Celsius, reflecting a steady improvement in science, weather observations, and computing power over the past 30 years.</p>
<p>But it’s not just about getting the maximum temperature right. Our ability to forecast important weather features has also improved dramatically over the past three decades. </p>
<p>For example, the recent <a href="http://www.abc.net.au/news/2015-07-13/new-south-wales-snow-damaging-roofs-felling-trees-ses/6614290">snowfalls in New South Wales</a>, which stretched into southeast Queensland, were highlighted nearly a week ahead by our weather models. And the wind change that was so influential on the fire behaviour on Black Saturday was predicted several days in advance. Such foresight would have been impossible over a decade ago. </p>
<h2>A brief history of weather forecasting</h2>
<p>In the pre-satellite era, the forecaster’s ability to analyse weather systems was limited by the availability of surface observations from weather stations. There were huge data gaps, such as over the Southern Ocean. Weather charts were hand-drawn, including the position of high and low pressure systems and cold fronts. High-impact weather events could catch communities by surprise.</p>
<p>In the early 1970s, the first weather satellites dramatically changed this, sending vital new information back to Earth that improved our understanding of Southern Hemisphere’s weather patterns. </p>
<p>At the same time, as supercomputing became cheaper and more powerful, numerical models began to replace the entirely manual analysis of early forecasters. </p>
<p>A forecast model solves fundamental equations of fluid dynamics and heat transfer to compute the evolution of the atmosphere with time (or “the weather”, in other words). While the basic formulae for doing this, based on Newtonian physics, have been known for almost a century, we had to wait for the growth in computing power to apply this knowledge to weather prediction.</p>
<p>The role of the forecaster continues to evolve as numerical prediction skill improves further and extra, more frequent, observations become available. </p>
<p>Ironically, rather than being challenged by limited information, modern forecasting techniques grapple with how best to assimilate the terabytes of data that flood in from all manner of observation sources and models.</p>
<h2>Our region’s next-generation satellite is now in orbit</h2>
<p>Modern meteorology is underpinned by satellites, providing real-time situational awareness, such as the position of a tropical cyclone, and the major initial input into weather models.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/92228/original/image-20150818-12389-10awnk1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Monitoring typhoons is a crucial job for weather satellites.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File%3AHaiyan_2013-11-07_0120Z.jpg">NASA/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>The main source of data comes from the polar orbiting satellites. These operate about 700 km above the Earth, roughly twice the height of the International Space Station. At these heights, the satellite observations are able to extract a vertical cross-section of the atmosphere, revealing such things as moisture, winds and temperatures.</p>
<p>Polar orbiting satellites scan the same area of the planet only twice a day which, if you are concerned about developing severe weather, is not frequent enough. For more frequent updates forecasters rely on satellites in a geostationary orbit.</p>
<p>At an altitude of 35,786 km above the Equator, a geostationary satellite has the same orbital period as the rotation of the Earth, and there is effectively no relative motion between the satellite and the ground. </p>
<p>For weather applications, this allows continuous monitoring of the area visible to the satellite, equating to roughly 40% of Earth’s surface. Visible and infra-red images of cloud cover from these satellites are familiar to most people, being routinely shown on television weather bulletins and on the Bureau of Meteorology’s <a href="http://www.bom.gov.au/australia/satellite/">website</a>.</p>
<p>In October last year, the Japanese Meteorological Agency launched the 3.5-tonne Himawari-8 satellite into geostationary orbit above the western Pacific region, the first of a new generation of advanced meteorological satellites. </p>
<p>It provides a significant increase in the spatial and temporal resolution of satellite images, increasing the spatial resolution to 500m and increasing the frequency to every ten minutes, giving forecasters rapid updates on developing meteorological conditions, particularly in areas without radar coverage. </p>
<p>A key benefit will be the ability to observe thunderstorm formation. Other benefits will be seen in the detection of tropical cyclone genesis, detection and tracking of bushfire movements using hotspot algorithms, improved observation of fog, and faster detection and analysis of volcanic eruptions.</p>
<p>From September 2015 the <a href="http://himawari8.nict.go.jp/">imagery from Himawari-8</a> will be available on the Bureau’s website.</p>
<h2>Improvements in Numerical Weather Prediction</h2>
<p>One of the biggest contributors to improved weather forecasts is the increase in supercomputing power. The Bureau’s new supercomputer – to be built by CRAY, costing A$77 million and funded by the Federal Government – will be the fastest in Australia when it becomes operational in mid-2016. </p>
<p>But it’s not a case of simply upgrading to new hardware – improved forecasts are dependent on taking advantage of the increased computing power. Over the next few years, the Bureau will use the supercomputer to implement a next-generation high-resolution weather forecasting model.</p>
<p>Weather forecasts start in the real world with data about what’s actually happening at the start of the forecast period. The data – including temperature, humidity, surface pressure and wind — collected from a variety of sources – are fed into models in a process known as data assimilation. </p>
<p>As the models improve, and more data becomes available, techniques for data assimilation must also be updated. </p>
<p>In the Southern Hemisphere, satellite data can make up more than 95% of the observational data fed into forecasting models.</p>
<p>Recently the Bureau tested a prototype forecast model in New South Wales with a resolution of 1.5 km and hourly updates. This type of high-resolution model can assimilate 10-minute data from Himawari-8, and allows us to capture thunderstorms and sea breezes that are too fine in scale for current forecast systems.</p>
<p>The forecast model takes all available observations and essentially evolves the simulated atmosphere forward in time to create the actual weather forecast.</p>
<p>The models do this by breaking the atmosphere up into small grid boxes or cells. The current regional model has cells that are 12 km wide - too large to represent individual clouds, which are typically hundreds of metres across. The model thus estimates these “sub-grid-scale” processes using physics. </p>
<p>As the resolution of the models increases, the sub-grid-scale physics has to evolve. This is both a boon and a challenge for forecasting. </p>
<h2>Get ready for new weather services</h2>
<p>Taken collectively, with the advent of the new satellite, supercomputer and advancing science, the public can expect a step change in weather forecasting services over the next decade. Improvements can be expected in near-real-time information for unfolding weather events, and improvements in lead times for forecasts that assist our warning, response and recovery efforts for severe weather.</p>
<p>As with all advances in technology, it is impossible to predict what some of the new service opportunities will be, as they connect with advances in communication and technology, but we know they’ll continue to evolve and excite, for both meteorologists and the public.</p><img src="https://counter.theconversation.com/content/44594/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>Moaning about weather forecasts is almost an Australian national pastime. But weather predictions have improved a lot, and with a new satellite and supercomputer, they are about to get even more reliable.Paul Gregory, BOM, Australian Bureau of MeteorologyAnthony Rea, Assistant Director, Observing Strategy and Operations, Australian Bureau of MeteorologyGary Dietachmayer, Atmospheric Modelling Team Leader, Australian Bureau of MeteorologyKarl Braganza, Manager, Climate Monitoring Section, Australian Bureau of MeteorologyLicensed as Creative Commons – attribution, no derivatives.