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Worrying about global tipping points distracts from real planetary threats

In a paper published today in Trends in Ecology and Evolution, Barry Brook and colleagues argue against the idea of an ecological global-scale “tipping point”. Here, Professor Brook outlines the paper’s…

Locally, tipping points are real, but it’s unlikely the whole globe will go at once. Truthout.org

In a paper published today in Trends in Ecology and Evolution, Barry Brook and colleagues argue against the idea of an ecological global-scale “tipping point”. Here, Professor Brook outlines the paper’s core argument, while Professor Corey Bradshaw (not an author on the study) explains what it means for conservation practice.

Barry Brook

We argue that at the global-scale, ecological “tipping points” and threshold-like “planetary boundaries” are improbable. Instead, shifts in the Earth’s biosphere follow a gradual, smooth pattern. This means that it might be impossible to define scientifically specific, critical levels of biodiversity loss or land-use change. This has important consequences for both science and policy.

Humans are causing changes in ecosystems across Earth to such a degree that there is now broad agreement that we live in an epoch of our own making: the Anthropocene. But the question of just how these changes will play out — and especially whether we might be approaching a planetary tipping point with abrupt, global-scale consequences — has remained unsettled.

A tipping point occurs when an ecosystem attribute, such as species abundance or carbon sequestration, responds abruptly and possibly irreversibly to a human pressure, such as land-use or climate change. Many local- and regional-level ecosystems, such as lakes, forests and grasslands, behave this way. Recently however, there have been several efforts to define ecological tipping points at the global scale.

At a local scale, there are definitely warning signs that an ecosystem is about to “tip”. For the terrestrial biosphere, tipping points might be expected if ecosystems across Earth respond in similar ways to human pressures and these pressures are uniform, or if there are strong connections between continents that allow for rapid diffusion of impacts across the planet.

These criteria are, however, unlikely to be met in the real world.

First, ecosystems on different continents are not strongly connected. Organisms are limited in their movement by oceans and mountain ranges, as well as by climatic factors, and while ecosystem change in one region can affect the global circulation of, for example, greenhouse gases, this signal is likely to be weak in comparison with inputs from fossil fuel combustion and deforestation.

Second, the responses of ecosystems to human pressures like climate change or land-use change depend on local circumstances and will therefore differ between locations. From a planetary perspective, this diversity in ecosystem responses creates an essentially gradual pattern of change, without any identifiable tipping points.

This puts into question attempts to define critical levels of land-use change or biodiversity loss scientifically.

Why does this matter? Well, one concern we have is that an undue focus on planetary tipping points may distract from the vast ecological transformations that have already occurred.

After all, as much as four-fifths of the biosphere is today characterised by ecosystems that locally, over the span of centuries and millennia, have undergone human-driven regime shifts of one or more kinds.

Recognising this reality and seeking appropriate conservation efforts at local and regional levels might be a more fruitful way forward for ecology and global change science.

Corey Bradshaw

Let’s not get too distracted by the title of the this article - Does the terrestrial biosphere have planetary tipping points? - or the potential for a false controversy. It’s important to be clear that the planet is indeed ill, and it’s largely due to us. Species are going extinct faster than they would have otherwise. The planet’s climate system is being severely disrupted; so is the carbon cycle. Ecosystem services are on the decline.

But - and it’s a big “but” - we have to be wary of claiming the end of the world as we know it, or people will shut down and continue blindly with their growth and consumption obsession. We as scientists also have to be extremely careful not to pull concepts and numbers out of thin air without empirical support.

Specifically, I’m referring to the latest “craze” in environmental science writing - the idea of “planetary tipping points” and the related “planetary boundaries”.

It’s really the stuff of Hollywood disaster blockbusters - the world suddenly shifts into a new “state” where some major aspect of how the world functions does an immediate about-face.

Don’t get me wrong: there are plenty of localised examples of such tipping points, often characterised by something we call “hysteresis”. Brook defines hysterisis as:

a situation where the current state of an ecosystem is dependent not only on its environment but also on its history, with the return path to the original state being very different from the original development that led to the altered state. Also, at some range of the driver, there can exist two or more alternative states

and “tipping point” as:

the critical point at which strong nonlinearities appear in the relationship between ecosystem attributes and drivers; once a tipping point threshold is crossed, the change to a new state is typically rapid and might be irreversible or exhibit hysteresis.

Some of these examples include state shifts that have happened (or mostly likely will) to the cryosphere, ocean thermohaline circulation, atmospheric circulation, and marine ecosystems, and there are many other fine-scale examples of ecological systems shifting to new (apparently) stable states.

However, claiming that we are approaching a major planetary boundary for our ecosystems (including human society), where we witness such transitions simultaneously across the globe, is simply not upheld by evidence.

Regional tipping points are unlikely to translate into planet-wide state shifts. The main reason is that our ecosystems aren’t that connected at global scales.

The paper provides a framework against which one can test the existence or probability of a planetary tipping point for any particular ecosystem function or state. To date, the application of the idea has floundered because of a lack of specified criteria that would allow the terrestrial biosphere to “tip”. From a more sociological viewpoint, the claim of imminent shift to some worse state also risks alienating people from addressing the real problems (foxes), or as Brook and colleagues summarise:

framing global change in the dichotomous terms implied by the notion of a global tipping point could lead to complacency on the “safe” side of the point and fatalism about catastrophic or irrevocable effects on the other.

In other words, let’s be empirical about these sorts of politically charged statements instead of crying “Wolf!” while the hordes of foxes steal most of the flock.

Join the conversation

59 Comments sorted by

  1. Comment removed by moderator.

  2. Tim Scanlon

    Debunker

    But I would have thought that there is a point of "inevitability" where it doesn't matter what you do, the problem is too far gone. E.g. too few animals of a species left to repopulate the species. Isn't that a tipping point?

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  3. Stephen Ralph

    carer at n/a

    Hi there

    you said - The planet’s climate system is being severely disrupted; so is the carbon cycle. Ecosystem services are on the decline.

    But – and it’s a big “but” – we have to be wary of claiming the end of the world as we know it, or people will shut down and continue blindly with their growth and consumption obsession.

    ****

    Wouldn't a sort of reverse situation be applicable, whereby people will get complacent and react along the lines of - oh well everything's localised, and it…

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    1. Jeff Poole

      logged in via Facebook

      In reply to Stephen Ralph

      There seems to be a widespread fear of the exponential function these days.

      I also very much doubt they've factored in any mass migration of the exponentially increasing human population as the melting of the Ice Cap destroys Northern Hemisphere agriculture...

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    2. Stephen Ralph

      carer at n/a

      In reply to Jeff Poole

      Hi Jeff

      as everyone may know I have NO qualifications whatsoever, so run the risk of making a fool of myself every now & then (or more, depending if you know me or not).

      After I'd written the comment, I wondered if every "model" using the future as its end point(s) used exponential functionality.

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  4. Anthony Nolan

    logged in via email @hotmail.com

    So we should think globally and act locally. Carry on then.

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  5. David Clerke

    Teacher

    The most quoted tipping point is the two degrees for global warming, there have been claims that this two was a political compromise because different self styled climate scientists were coming up with widely differing figures. Can any one verify or deny this two degree figure was arrived at on that basis?

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    1. Mike Hansen

      Mr.

      In reply to David Clerke

      In your desperation to troll the article you did not read it. Try again and you may learn what a tipping point is.

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    2. Mike Hansen

      Mr.

      In reply to David Clerke

      And the answer is that you are a troll called John Coochey dishonestly hiding behind your sockpuppet David Clerke.

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    3. David Clerke

      Teacher

      In reply to Mike Hansen

      Now answer the question if you can. Apparently not. Of course tipping points are of no validity if they are numbers pulled out of the air, If different studies come up with widely different tipping points then the same applies.

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    4. Tim Scanlon

      Debunker

      In reply to Mike Hansen

      His trolling extends to posting the same question that was removed by the moderators only a few hours ago.

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    5. David Clerke

      Teacher

      In reply to Tim Scanlon

      But still you do not have an answer? The real question is why it was removed. It was politely phrased and a straight question. Seems the Politically Correct find such things offensive.

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    6. Tim Scanlon

      Debunker

      In reply to David Clerke

      "David", you always come into a thread with unrelated questions and spurious claims. It would be the equivalent of me going into an article on why the federal Greens party sucks and starting asking about Senator Xenophon's latest antics. Irrelevant and nothing but annoying trolling. I expect all of these posts will be deleted soon so that real discussion can ensue on the actual topic of the article.

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    7. David Clerke

      Teacher

      In reply to Tim Scanlon

      And the answer is? If a comment on an article about tipping points asks how such tipping points are arrived at is not relevant what comment is? Or are discussions on this blog and similar simply a form of mutual onanism designed the reassure the politically correct?
      I am reminded of Dr Karl's recent utteradges about what Pachuari said or did not say which are so easily checked and rebutted because of the web. A few decades ago it would take lengthy efforts in a good reference library to find out he truth,

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    8. Greg Edeson

      PhD candidate at School of Geography and Environmental Studies, University of Tasmania

      In reply to David Clerke

      Whenever I see a post from David Clerke I get David Bowie's Starman running through my head, but it only has two lines:
      "There's a strawman waiting in the wings,
      he'd like to be constructive but he thinks he'd blow our minds"
      Have to go listen to the real song to purge this from my head before the weekend.

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  6. Felix MacNeill

    Environmental Manager

    The point that different ecosystems will behave differently makes very good sense but, in the long run, doesn't it end up being a bit like arguing about whether you'd rather step in dog shit, cat shit or cow shit?

    I mean simply that the evidence suggests that while a few local areas/ecosystems may be better off, at least for a time, in the great majority of cases things will be worse...well, 'worse' is an awkward term, but surely that fact that most of the world's ecosystems, albeit in different…

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    1. Mike Hansen

      Mr.

      In reply to Felix MacNeill

      Felix.
      You would probably have to read the articles to fully grasp what Brooks is arguing against.

      I have found the papers in PDF form - unfortunately I am too busy to read them at the moment but they are here.

      Approaching a state shift in Earth’s biosphere (“planetary tipping points”)
      http://www.stanford.edu/group/hadlylab/_pdfs/Barnoskyetal2012.pdf

      A safe operating space for humanity ("“planetary boundaries”)
      http://www.environment.arizona.edu/files/env/profiles/liverman/rockstrom-etc-liverman-2009-nature.pdf

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  7. Shane Perryman

    logged in via email @gmail.com

    It would be helpful if the source document were not behind a $US37.95 paywall.

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  8. Jeff Poole

    logged in via Facebook

    Wow! Alleged scientists who've never heard of latent heat! I wonder if they've ever noticed that when the ice melts in their gin the whole volume, not just the top layer, warms up quickly...

    Not connected enough eh?

    Tell that to the people in the US Great Plains, currently suffering their most instense drought due to the disruption of the jetstream caused by the melting Ice Cap.

    And this article happily ignores the huge release of methane, currently happening up there in the arctic. A release of methane that is taking us into runaway warming right now.

    This strawman argument cheerfully ignores the simple truth that a tipping point is an irreversible point - and it may take a few years. I suggest the authors have a go at refreezing the Arctic after the ice cap vanishes in summer sometime this decade.

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    1. Mike Hansen

      Mr.

      In reply to Jeff Poole

      Jeff. Barry Brook is not a climate science denier. As Shane points out the actual article is behind a paywall so I would reserve judgment until you are able to read it.

      And it is simply not true that "a release of methane that is taking us into runaway warming right now".

      Runaway warming describes something quite specific for planet earth. As climate scientist Chris Colose notes in this Skeptical Science article "As a final note, it's worth mentioning that it is virtually impossible to trigger…

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    2. Jeff Poole

      logged in via Facebook

      In reply to Mike Hansen

      If I thought he was a science denier I would have used those words.

      This is not that kind of blind denial - it's a bit subtler.

      Let's call it "Linear Optimism".

      The belief that Earth's systems will always behave in a linear fashion...

      Now remind me. When did the Linear Optimists of the IPCC say that we'd lose the northern Ice Cap in summer? End of the Century wasn't it?

      Now we know that around 70% of the ice has gone in 50 years or so and we'll have our first look at an ice free…

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    3. Liam J

      logged in via email @gmail.com

      In reply to Tom Keen

      Thanks for link, much more interesting.
      "We need to inundate schools – from primary to university – with the mind-blowing reality of what we’re doing to our only home."
      Sure, so long as at the same time we inform and empower students and their families on their ability to act & adapt now. Waiting for Martin Fergusen or Mitch Hook to grow a concience hasn't worked.

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  9. Aden Date

    Service Learning Coordinator at University of Western Australia

    When I think of "tipping points," I tend to think of local areas that will enter precipitous exponential change as a result of rising temperatures, but these local areas have planetary impacts.

    For example, melting arctic ice is a "local" tipping point but the implications of this local loss are global, as the thermodynamic effects of dark heat-trapping water rapidly spread throughout the world via. ocean currents.

    Similarly, the melting of the Siberian Permafrost is a "local" tipping point with global implications.

    I'm not sure I wholly understand the author. Our ecosystems are not homogeneous? Climate change will impact upon different ecosystems differently (although, almost universally, in a way that is disruptive)? We won't wake up to Armageddon one day? This argument seems self-evident at best, and at worst, an attempt to pander to centrists with semantics.

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  10. Robert McDougall

    Small Business Owner

    i suppose its relative to the nature of the localised tipping point and the way thay has potential to impact on the global environment.

    I.e. the Arctic which i understand is one of the faster warming regions, reaches a "tipping point" whereby methane and co2 stored in ice sheets melts and releases the stored gases.

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  11. Philip Dowling

    IT teacher

    Perhaps it is time that people who have caused ecological tipping points by their actions should be named and shamed.
    Australia's megafauna disappeared because of human intervention.
    Australia's largely evergreen trees also seems to have been caused by human intervention.

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    1. Liam J

      logged in via email @gmail.com

      In reply to David Clerke

      David Clerke offtopic trolling again.

      If we donate do we get more moderators? This site is a great information commons, but all commons need active management.

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    2. Mitch Dillon

      logged in via Facebook

      In reply to Philip Dowling

      Actually, anthropogenic-induced megafauna extinction has been one of the hotly debated issues for decades. I doubt there's been any conclusive evidence produced lately to change that situation.
      The trees?
      The article points out the inadequacies of the the 'tipping point' idea.

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    3. Doug Hutcheson

      Poet

      In reply to Philip Dowling

      Philip, you said "Australia's megafauna disappeared because of human intervention". Do you have links to papers saying that? I thought the question was still open and there is no clear evidence (yet) that humans and megafauna co-existed in Oz.

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    4. Jane Rawson

      Editor, Energy & Environment at The Conversation

      In reply to Liam J

      If you see something bad, hit the flag button. Then we'll know.

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  12. Peter Boyd Lane

    geologist

    David Clerke ..... perhaps someone has answered, but thought the 2 degrees was a tipping point because it has been estimated that's when the permafrost would melt resulting in a methane (and CO2) "burp" and catastrophic global warming, by say 6 degrees

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  13. Glenn Tamblyn

    Mechanical Engineer, Director

    The concept of Tipping points is difficult, as the authors point out. But that doesn't mean it is wrong. Perhaps what is key to this is understanding the importance of scale. Scale geographically. Scale in time.

    Is the release of methane from Arctic permafrost a 'tipping point' when looked at on a scale of a decade or so? Maybe, a bit, sorta kinda. Is it a tipping point when measured on a scale of centuries? Absolutely.

    Is the possible decline in precipitation in the Amazon on a multi-decade…

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    1. Stephen Ralph

      carer at n/a

      In reply to Glenn Tamblyn

      Hi Glenn

      I guess if we don't really know what the tipping point(s) will be, then tragically we may find out.

      I think the debate is not what or when, but how we NEVER get to find out.

      By the time we get to the tipping point(s) it will be too late anyway.

      Its a bit like changing deck chairs on the Titanic - ultimately futile.

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    2. Stephen Ralph

      carer at n/a

      In reply to Stephen Ralph

      Remember back to the good old days of the Kyoto protocols - the summer of '97 - god how we laughed, and did bugger all.

      But we had a great time, the Japanese were wonderful hosts.

      And remember Bali in 2007 - oh the fun of it all. Again not a lot of progress, but my goodness the hinterland looked lovely at that time of year.

      And remember Copenhagen in 2009, another great chance to catch up with old friends. Did we achieve much, well the rhetoric was plentiful, as was the food and wine - remind me to tell you a story or two about what went on in the Tivoli.

      So my friends, where was I - oh yes when is the next big do - I can't wait.

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  14. Geoff Russell

    Computer Programmer, Author

    Whether or not there are global tipping points is a scientific question. Let's suppose, contrary to the article, that there are. ie., that at some level of climate forcing (not just ppm CO2) it won't matter what we do, there will be enough local changes that to destroy our capacity to feed 7-10 billion people. This only requires the destruction of the reliability of crop harvests in the global food bowels. Grains provide 45% of global calories ... (cf. beef just 1.4% from 1.4 billion animals…

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  15. takver takvera

    Journalist and Editor at Indymedia

    An interesting article. I had to read it a second time to pick up the focus on global ECOLOGICAL tipping points. But ecosystems are connected through atmospheric and oceanic changes. We are changing the climate of the planet and are likely to / perhaps have already triggered some major regional climate tipping points that will have a planetary impact. These will impact regional ecosystems which will respond in different ways and will change at different rates. Indeed, each may have its own tipping…

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  16. john tons

    post graduate student

    What this article illustrates is the disconnect between politics and science. Politicians attempt to solve a global problem of climate change. The real challenge is to create resilient domestic economies that can endure in the face of climate change and rapid resource depletion. Instead we see the debate on initiatives like the carbon tax being sold to us as our bit to save the planet and it is on that basis that the those opposing the tax have string grounds for opposing it. If on the other hand the aim of the tax was to wean ourselves off reliance on fossil fuels we might, just might get a more informed debate about future proofing Australia. But I would't hold my breath. I suspect in the end Lovelock may well be right - if we are lucky (or unlucky?) we may end up with a situation where around the globe there are small remnants of humanity capable of starting the experiment all over again.

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    1. Stephen Ralph

      carer at n/a

      In reply to john tons

      Hi John

      be nice tho if politicians wouldn't have to be all that resilient in the face of climate change and rapid resource depletion. Resilience implies acceptance.

      I just don't get that for all of us, this is the most important issue of all. There has never been a situation where the future of the whole world is at stake, and very little of substance has been done. Its all yak yak yak.

      (and yes the issue of nuclear oblivion was a world wide issue, and yes it still could be)

      And I don't like the idea of politicians attempting to solve global problems of climate change - I WANT THEM TO SOLVE THEM.

      If they don't who else can we turn to.............

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    2. john tons

      post graduate student

      In reply to Stephen Ralph

      I do not disagree and global initiatives should continue. But if we framed the debate in terms of what needs to be done locally to address climate change in terms of domestic self interest then politicians have a far better chance to get beyond the yakkiti yak phase. It will mean that globally there will be a range of different initiatives all centred on reducing our dependence on fossil fuels; we just might get sufficient traction to encourage a global regime where developing countries are given the means to skip the carbon cycle of industrialization.
      I do disagree with one aspect of your comment. We need to move away from the paradigm that the role of politicians is to solve problems - I just want them to get out of the way and let us solve the problems

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    3. Stephen Ralph

      carer at n/a

      In reply to john tons

      Hi John

      If there's one thing I have learnt from The Conversation - it's very hard to get a consensus on anything.

      Everyone has their own idea of how to solve things (including me of course).

      So when you say "us" - who exactly is us, and how would it work.
      another committee - another kyoto or copenhagen?

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    4. john tons

      post graduate student

      In reply to Stephen Ralph

      Consensus no but hopefully we can get to some sort of highest common factor (as opposed to the lowest common denominator) I do think a Rawlsian social contract model could work but probably only on a very small scale. The research that Ostrom has done on managing the global commons indicates that small communities can manage their own resources without falling prey to a tragedy of the commons scenario. Likewise examples like the transition town movement are promising initiatives. We can make quite…

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    5. Stephen Ralph

      carer at n/a

      In reply to john tons

      Hi John

      yep - like that thinking....change from the grass roots upwards.

      I'm reminded of the towns in Victoria that have successfully lobbied against pokies. One (Romsey) that succeeded in keeping pokies out of the town, and Castlemaine, where an increase in pokie machine numbers was vetoed.

      I like playing the pokies, but if the majority in a town have a view contrary to mine, then so be it.

      Here in Torquay, development in the Spring Creek area of town was quashed b/c of people power…

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  17. Alex Cannara

    logged in via Facebook

    "...at the global-scale, ecological “tipping points” and threshold-like “planetary boundaries” are improbable. Instead, shifts in the Earth’s biosphere follow a gradual, smooth pattern." -- amazing!

    The lack of respect for knowledge is breathtaking.

    Let's just " be empirical" on world temps/ice/climate -- the Milankovitch Cycles provide clear "tipping points" every 90+ thousand years or so. Right now, we're emitting CO2 faster and raising average world temps faster, than at any time in the…

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  18. Greg Edeson

    PhD candidate at School of Geography and Environmental Studies, University of Tasmania

    This article is following the very productive trend away from global and regional generalisations and trends, into the way we actually experience climate change - in jolts, with peaks and troughs, where similar physical changes are experienced differently even within a few 10s of kilometres.

    Day after tomorrow type scenarios are unlikely (as far as I know), but the gradual but inexorable change in local systems around the world, and the evidence that links them to one key driver (CO2) suggests…

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  19. Dan Cass

    Lobbyist for the forces of good at Dan Cass & Co

    I'm always interested in new approaches to understanding the global ecological crisis and how to fix it.

    I've not read the journal article because I don't have access, but it seems to me that this is a flimsy thesis, at best.

    In fact I'm struggling to see what the point is.

    Perhaps Barry has relevance deprivation syndrome, now that the 'nuclear renaissance' has collapsed and he's fishing around for a way to stay in the media spotlight?

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    1. Geoff Russell

      Computer Programmer, Author

      In reply to Dan Cass

      Hi Dan, clearly you aren't paying attention. China is not only building plenty of big nukes, she is preparing to mass produce SMRs (small modular reactors). By 2020 she expects to be producing about 600 terawatt hours per year of nuclear and 30 TWh/yr of solar, and to have HTR-PMs beginning production. The US is now scrambling to bring mPower on line so that she isn't left too far behind. Russia and South Korea are also in the race. France has been producing electricity for <80g-co2/kWh for 20 years while Germany is at 461 g-co2/kwh and rolling out even more coal. The anti-nuclear movement has cost us two decades and, together with the cattle industry, bought the planet to its knees.

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    2. Geoff Russell

      Computer Programmer, Author

      In reply to Geoff Russell

      P.S. Personally I think the US is stuffed. It has allowed the anti-nuclear movement to slow development to a crawl so the mPower won't be produced in volume soon enough to be relevant.

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    3. Dan Cass

      Lobbyist for the forces of good at Dan Cass & Co

      In reply to Geoff Russell

      Thats a bit doom and gloom about the US.

      I love America for its innovation and optimism so I guess I'm biased enough to think it will rise above the energy / climate crisis!

      China already has more wind than nuclear power. Game over, Geoff. The nuclear renaissance was only ever a PR exercise and I'm sorry you got sucked in.

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    4. Geoff Russell

      Computer Programmer, Author

      In reply to Dan Cass

      "China already has more wind than nuclear power" ... how do you come by that claim Dan? Wikipedia has China generating 73 TWh/yr in 2011 from Wind and the World Nuclear Association has about 14 GWe of nuclear currently operating ... 14*24*365*0.9=110 TWh/yr but with almost double that amount under construction.

      Last time I checked 110>73 .. and it's unlikely they added 37 TWh/yr last year.

      Even if your claim was true, it wouldn't compensate for the comparative build speed of nuclear. France with just 55 million people added 200 TWh/yr during the 1980s.

      Checkout windpower build rates in Germany http://en.wikipedia.org/wiki/Wind_power_in_Germany

      It's moving from exponential to linear and slowing down as the good sites get used and you run out of habitat to trash with roads and infrastructure. Here's an interesting little clip

      https://www.youtube.com/watch?feature=player_embedded&v=zc7rRPrA7rg#!

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    5. Dan Cass

      Lobbyist for the forces of good at Dan Cass & Co

      In reply to Geoff Russell

      You've made 479 comments on The Conversation (not including the ones that were deleted....). Wow.

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    6. Geoff Russell

      Computer Programmer, Author

      In reply to Dan Cass

      And your point? ... deflection perhaps?

      I'm still interested in why you said there was more wind in China than nuclear when it looks clear from reasonable evidence that there isn't. Did you just make the claim up? Or did you just repeat it with out checking? If so, where did it originate?

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    7. Geoff Russell

      Computer Programmer, Author

      In reply to Mike Hansen

      Thanks Mike. Now at least we have a source and its consistent with mine except that my estimate of the nuclear capacity factor was too high. I'll keep that in mind.

      Interestingly, if they are really only getting 100 TWh/yr out of 75.6 GW with 80% connected then they are only getting about 20% capacity factor which is surprisingly low.

      I'm still betting wind levels off by 2020 as it is already doing in Germany, whereas nuclear will do what it did everywhere in the 70s and 80s ... accelerate. Building wind in China will get increasingly tougher as supply chains get longer. Whereas nuclear will get only get faster. Keep in mind that when France and the US were rolling out nuclear in the 1970s, the Chinese were still shooting scientists. So their development has started from a long way behind the 8-ball.

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  20. trevor prowse

    retired farmer

    If you look at the global death rates due to various types of events ,such as droughts, floods, windstorms , slides, waves/surges, extreme temperatures and wild fires , the death rates per year , per million people from 1900-1989 was 94.16 and from 1990-2006 was 4.87. ---source EM-DAT(2007) McEverdy and Jones. If the tipping point was so serious, these statistics seem to show that we may be able to stabalise the environmental effects by looking at the adaption features , rather than being pushed…

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