David Stockwell writes about a book review that was written back in May this year by Dr Daniel Botkin. I didn't know of David Botkin but his blog lists considerable credentials in ecology. He's written a couple of books, the latest one seems to be an attempt at drawing together ecology and human mythology or folklore. But that's just from reading the first few pages. It could be about something completely different. He's been retired since 1992 and doesn't do much more than write book reviews these days, plus that book I mentioned. Based on some of his writings, he definitely accepts the world is warming and it's caused by human activity. However he only seems to accept some of the science. Going by this article in the Wall Street Journal he is a science denier because he cannot accept that global warming will have the consequences that science predicts it will bring.
The book Daniel was reviewing is called Saving a Million Species: Extinction Risk from Climate Change and is edited by Lee Hannah. It is described on the CSIRO website as:
The research paper 'Extinction Risk from Climate Change' published in the journal Nature in 2004 created front-page headlines around the world. The notion that climate change could drive more than a million species to extinction captured both the popular imagination and the attention of policy-makers, and provoked an unprecedented round of scientific critique.
Saving a Million Species reconsiders the central question of that paper: How many species may perish as a result of climate change and associated threats? Leaders from a range of disciplines synthesise the literature, refine the original estimates, and elaborate the conservation and policy implications.
Saving a Million Species offers a clear explanation of the science behind the headline-grabbing estimates for conservationists, researchers, teachers, students, and policy-makers. It is a critical resource for helping those working to conserve biodiversity take on the rapidly advancing and evolving global stressor of climate change – the most important issue in conservation biology today, and the one for which we are least prepared.
Daniel applauds some of the book but not all of it. Because he's been away from his field for more than 20 years now, and because he seems to reject the latest science about climate, I'll take Daniel Botkin's belated book review with a grain of salt. Bear in mind, though, that I'm no ecologist.
I'm on firmer ground rejecting David Stockwell's article. Dr David Stockwell is writing for the anti-science blog WUWT, I'll take a very large pinch of salt with his WUWT article. I don't particularly care that David Stockwell is himself an ecological modeler. I'll still reject outright some of his WUWT article. For example, David Stockwell wrote about a quote from the August 2013 Introduction to a special issue on climate change:
The starting point of any objective analysis is to examine one’s assumptions, and the trajectory of global warming is surely the most central. The IPCC’s projections are the typical starting points for any scientific study of climate change’s effects on species. Science provides an example:
“Even the most optimistic estimates of the effects of contemporary fossil fuel use suggest that mean global temperature will rise by a minimum of 2°C before the end of this century and that CO2 emissions will affect climate for tens of thousands of years. ”
Yet climate sensitivity to atmospheric CO2 has been downgraded in the latest IPCC report, and so should the forward projections. The observed rate of warming is less than 0.2C per decade, and so below 2°C, and well below the minimum warming scenario of 1.25C by 2050 or 0.25C per decade used in Thomas et al 2004.
David Stockwell is wrong, of course. For starters, Thomas' minimum warming scenario (see the supplement) was SRESB1 and a rise of 0.9 degrees Celsius by 2050, not 1.25 degrees. He's also wrong about the IPCC. The IPCC has widened the estimate of climate sensitivity. It has dropped the lower end - though I believe it is wrong to do so but it hasn't specified an actual number - only a range. So it can't be described as "downgraded" IMO. It's kept the upper end of the range the same. Also, the IPCC indicates that mean global surface temperature will indeed be at least 2 degrees higher than the turn of the twentieth century under any realistic emissions trajectory. From the Summary for Policy Makers page SPM-15:
Global surface temperature change for the end of the 21st century is likely to exceed 1.5°C relative to 1850 to 1900 for all RCP scenarios except RCP2.6. It is likely to exceed 2°C for RCP6.0 and RCP8.5, and more likely than not to exceed 2°C for RCP4.5. Warming will continue beyond 2100 under all RCP scenarios except RCP2.6. Warming will continue to exhibit interannual-to-decadal variability and will not be regionally uniform.
All that is a red herring when it comes to extinctions. Although they are probably happening all the time, we only notice them when they are species we already know about. In regard to biodiversity and ecology, David Stockwell drops a few different notions, such as neutral theory - which is described here as being that most genetic variation in populations is from genetic drift and mutation, not adaptation. That doesn't sound implausible. But that doesn't mean that more species won't become extinct with climate change. If a population isn't able to adapt to a changed environment and can't relocate to another environment that does suit them, then they won't survive. Simple really.
One of David's arguments is:
Expected species’ extinctions from climate change are derived from Species Area Relationships (or SARs), which is an empirical relationship between an area of habitat, such as forest or grassland, and the number of species it contains. A statistical method called Niche Modelling is used to extrapolate the area of suitable habitat of a species before and after climate change. The species with reduced area are selected (I would say ‘cherry-picked’) and then the average areal loss is plugged into the SAR relationship to give the number of species lost in a given climate change.
The problem of ‘circular reasoning’ with the SAR method was raised here and in Botkin’s“Forecasting the effects of global warming on biodiversity”, and stems from the accentuation of the losers and deprecation of the winners. Due to the cherry-picking of species with areal reductions, any change at all increases extinctions, and so the outcome is predetermined. The circular fallacy can be further illustrated by imaging what would happen in a global cooling scenario. SAR-based methods would cherry-pick the species that lose habitat due to cooling and so again predict an increase in extinctions. The SAR method is biased and decidedly anti-change.
Maybe I'm being slow, but I don't know why he calls this circular. Thing is that species reduction will occur with a large rapid warming and a large rapid cooling. There's nothing circular about that. It takes a long time to recover after major changes and particularly after rapid changes, like we're bringing about.
As an aside, here is an article describing species area relationships. Here are some slides describing niche modeling. And here is a paper by Jane Elith et al (2010) exploring an approach to modelling future distributions of species, given the pressures from species invasions and climate change. I don't see why David is so dismissive of efforts to predict biodiversity and species distribution and extinctions and the rate of same.
David finishes up with a typical denier strawman question and statement:
How can a scientific assessment be objective when the methods themselves are of dubious validity, and still highly contentious? A balanced appraisal would highlight the ecological theory, paleo-evidence and respected opinion that suggests it is plausible, and even likely, that moderate climate change is not harmful to species diversity and may even be beneficial.
First of all, David isn't one to talk about being "objective". He's got his own agenda. Thing is that it's almost impossible for anyone to be purely objective about anything (there's almost always some subjectivity involved). Secondly, he seems to think that "respected opinion" suggest that moderate climate change may be beneficial. Who knows, it might indeed, particularly if humans were to reduce in numbers. However the world is going through immoderate climate change, it is on pace to heat up ten times faster than it has in 65 million years, and that will certainly hasten the sixth major extinction.
Lists of extinctions and endangered speciesWikipedia list of extinct animals
IUCN Red List
Committee on Recently Extinct Organisms
Thomas, Chris D., Alison Cameron, Rhys E. Green, Michel Bakkenes, Linda J. Beaumont, Yvonne C. Collingham, Barend FN Erasmus et al. "Extinction risk from climate change." Nature 427, no. 6970 (2004): 145-148. doi:10.1038/nature02121
From the WUWT comments
laterite thinks that habitats just pick up and shuffle off when it suits them and says (excerpt):
December 6, 2013 at 1:32 am
Peter Miller: Hotter generally means more species except in deserts, so there are exceptions. The thing about climate change is that as a process, no habitat is destroyed – it moves – that’s all.
james griffin mysteriously talks about the "last six Holocene's" (sic) and says (excerpt):
December 6, 2013 at 3:32 am
The empirical data from the last six Holocene’s including our own all show temperatures warmer than today and therefore the premise that a degree or two of warming would wipe out many species is nonsense.
mkelly seems to be confusing discovery of species with evolution of new species and is mistaken when saying:
December 6, 2013 at 6:38 am
The new species found in the past 500 years far exceeds the ones gone extinct. Just recently a small jungle cat species was found.
ferd berple has his own weird and nonsensical "theory" as he often does and says:
December 6, 2013 at 7:27 am
after every mass extinction event in the earth’s history there has been an explosion of new species. death is not a mistake by nature, it is an invention of nature to ensure that species can adapt over time. unless the present generation dies they will consume the food required by the next generation, making the next generation less successful and less likely to survive. as it is with generations, so it is with species.
Craig Loehle is, believe it or not, boasting that he's publishing a paper in the "journal" Energy and Environment and says:
December 6, 2013 at 7:51 amThere's a recent PNAS paper about how trees can protect cold climate plants from global warming to some extent.
I have a paper coming out in early 2014 in Energy & Environment showing that cold climate trees are very tolerant of warming and unlikely to suffer at all.
Jim G says "science is too hard, why bother":
December 6, 2013 at 8:13 am
“Only two things are infinite, the universe and human stupidity, and I’m not sure about the former.” – Albert Einstein. Science should attempt to avoid delving into fiction as much as possible. We do not even know all the species which are, let alone those that are no longer. At least these analyses should be noted as what they are, pure speculation, including any attempts at putting numerical values on species lost over virtually any time span. Even more ridiculous is any attempt to state the causal variables for such extictions. Too many possible unknown variables.