(Image source: League of Conservation Voters)
In desperately scanning through the IPCC’s preliminary 4th assessment report for any shred of good news, perhaps in hopes of delaying a transition away from fossil fuels that needs to begin now and complete by 2030-40 if we’re to have much hope of ensuring a climate in which human civilization won’t face catastrophe, The Economist found a bright little cherry. It reproduced a preliminary graph from a non-physical sciences group showing lower than scientific consensus estimates for temperature increase through 2100 and conflated it with an entirely Economist-manufactured news item erroneously stating scientists are finding climate sensitivity is lower than previously expected (Hint: it’s not).
I’m not going to re-publish the graph, as it’s entirely misleading, but I will re-publish what The Economist says about it:
Still, over the past year, several other papers have suggested that views on climate sensitivity are changing. Both the 2007 IPCC report and a previous draft of the new assessment reflected earlier views on the matter by saying that the standard measure of climate sensitivity (the likely rise in equilibrium temperature in response to a doubling of CO2 concentration) was between 2°C and 4.5°C, with 3°C the most probable figure. In the new draft, the lower end of the range has been reduced to 1.5°C and the “most likely” figure has been scrapped. That seems to reflect a growing sense that climate sensitivity may have been overestimated in the past and that the science is too uncertain to justify a single estimate of future rises.
Note the Economist’s highly speculative use of the words ‘suggest’ and ‘seemed.’ And ‘scientists,’ in this case, apparently include only those on the low end of climate sensitivity estimates, rather than the more likely to be accurate consensus range. Research on the middle or high end, likewise, is completely ignored.
Quibbling Over Equilibrium Sensitivity
The Equilibrium Climate Sensitivity (ECS) The Economist refers to is how much Earth temperatures are expected to rise when one includes fast feedbacks such as atmospheric water vapor increase and the initial greenhouse gas forcing provided by CO2. Consensus science, despite The Economist misinforming us to the contrary, finds Equilibrium Climate Sensitivity to be about 3 degrees Celsius for each doubling of CO2. So we get around 3 degrees Celsius of rapid warming at 550 parts per million, according to mainstream science. The Economist’s misleading quibble is trying to suggest that this level is closer to 2 degrees Celsius or the ludicrously unsupportable 1.5 degrees Celsius. Measures that, even if it were true (it’s not), would buy us, at most, another decade or two of business as usual emissions.
As unfortunate as the Economist’s cherry picking has become, it doesn’t even melt the tip of the iceberg or permafrost, for that matter. Because if you include the ‘slow feedbacks’ that ECS leaves out you end up with double the amount of warming long-term. So 550 parts per million gets us to a scorching 6 degrees Celsius Earth Systems Sensitivity (ESS) once melting ice sheets, methane release, and permafrost thaw are included (consensus estimates, not what The Economist cherry picked). The Economist also seems to ignore the blatant fact that such feedbacks are emerging now. Amplifying methane release in the Arctic has been visible since the mid 2000s and Greenland and West Antarctic melt rates have been increasing at an exponential rate since about 1995.
Confirming these observations is a new paper showing Greenland ice sheet response is happening faster than scientists expected. With the Greenland ice sheet melting like butter now and not 100 years from now as IPCC originally expected, the Equilibrium Climate Sensitivity measure and its inherent assumption that ice sheet and tundra response will be slow, seems to be shaping up as too conservative. Yet, The Economist remains enchanted with the notion of warping these already conservative estimates to pad its own, more comfortable, view of reality.
How’s the sand you’ve got your head buried in, Economist? Soft and white? Watch out, heads buried in the sand tend to bake these days.
What should be the news all responsible mags are reporting is that the ‘slow feedbacks’ aren’t really so slow after all. Under the very rapid pace of human forcing of at least 10 times anything we can find in the geological record Greenland melt, Antarctic melt, tundra melt and methane release are coming into play now. All taken together, they will more than double the human forcing. Terrifying news that should have all responsible persons and governments pushing for a rapid response, not grasping for the lowest hanging cherries in the science reports.
So the real measure we should be concerned about now is the one that includes all or most of the feedbacks — the Earth Systems Sensitivity (ESS) we noted above. The real total estimate of warming that is at least twice the academic ECS estimate The Economist so desperately tried to water down.
Yet the magazine behaves well contrary to prudent logic as it merrily runs with its false claim that climate scientists are saying ‘we’re sorry we scared you, climate sensitivity is less than we previously expected.’ Sad to say, The Economist is entirely involved in the now too common journalistic sin of climate science misinformation via massaged data.
The good news is that The Economist article might be less dreadful than it could have been. For instance, I didn’t find any typos…
The Economist seems blissfully unaware that while the Thawing Permafrost Could Cause 2.5 Times the Warming of Deforestation (!) and add up to 1.5°F to warming in 2100 by itself, “Participating modeling teams have completed their climate projections in support of the [IPCC’s] Fifth Assessment Report, but these projections do not include the permafrost carbon feedback.”
The Economist also seems blissfully unaware of the fact that we are currently close to the 1000 ppm emissions pathway. And The Economist also seems blissfully unaware that stabilizing anywhere near 450 ppm atmospheric concentration of CO2 would require immediate and sustained action to replace the world’s fossil fuel system with one based on carbon-free energy — precisely the kind of aggressive action this piece seems designed to undercut.
For my part, I’d prefer more typos and less misleading information on the science.
Perhaps The Economist should take a look at the best of the best among climate scientists — notably James Hansen who warns that Equilibrium Climate Sensitivity is at least 3 degrees Celsius and that this estimate is probably conservative. Hansen finds that under business as usual greenhouse gas emissions we reach a scorching 7 degrees Celsius warming and very catastrophic 1,000 parts per million CO2 by the end of this century (if we somehow manage to hold industrial civilization together after we blow through 2, 4 and 6 degrees Celsius worth of warming, which is highly unlikely). The final warming in such a case, Hansen shows, would be between 10 and 14 degrees Celsius — enough to trap the climate in a PETM-type warming in less than one century, and blast humans with large areas of lethal 35 degree Celsius or greater wet bulb temperatures. A mass extinction event for us humans and all other life too.
Michael Mann, another top climate scientist The Economist ignores by sticking its fingers in its ears and chanting ‘nanananana’ notes:
Among other things, the author [of the Economist’s report] hopelessly confuses transient warming (the warming observed at any particularly time) with committed warming (the total warming that you’ve committed to, which includes warming in the pipeline due to historical carbon emissions). even in the best case scenario, business as usual fossil fuel burning will almost certainly commit us to more than 2C (3.6 F) warming, an amount of warming that scientists who study climate change impacts tell us will lead to truly dangerous and potentially irreversible climate change. the article does a disservice to Economist readers by obscuring this critical fact. Sadly, it is hardly the first time in recent history that the Economist has published flawed and misleading stories about climate change.
Mann shows that The Economist clearly misses some very basic principles of climate science by confusing projected warming at a particular point in time with final warming. And that’s a big problem. Because temperatures will continue to move higher for decades, even if we were to halt emissions immediately, which is clearly not in the Economist’s plans. The Economist’s plans, instead, seem to include locking in more dangerous exploitation of fossil fuels.
Since the Economist clearly can’t handle ECS, it should stick with Paleoclimate, which is much less murky. And by looking back into Earth’s geological history we find temperature increases at these ranges for these levels of carbon dioxide:
350-400 parts per million: 3 degrees (C) worth of temperature increase long-term (Greenland and West Antarctica melt).
400-450 parts per million: 4 degrees (C) worth of temperature increase long-term.
450-500 parts per million: 5 degrees (C) worth of temperature increase long-term.
500-600 parts per million: 6 degrees (C) worth of temperature increase long-term (No major glacial ice left).
600-700 parts per million: 7 degrees (C)…
700-800 parts per million: 8 degrees (C)…
800-1200 parts per million: 9-12 degrees (C)…
Add to these observed past warming levels the fact that the rate of forcing was much slower than the human rate of forcing. So if more forcing means more feedback, even the harsh Paleoclimate evidence is too conservative a measure. Hansen and others warn of ‘unexpected consequences’ from the rapid pace of human forcing. And it would ‘seem’ that one of these nasty surprises is an already observed faster than usual rate of ice sheet and methane response.
Climatologist Kevin Trenberth is another scientist The Economist seems to be happy to ignore. But, perhaps, they should listen and learn something. In a letter to Joe Romm, Kevin stated:
The Working Group III IPCC report [on mitigation which the Economist used in its most recent attempt to misinform on climate sensitivity] is no where near final, the final draft has not even been produced yet. Moreover WG III is not responsible for making any statements about climate sensitivity and have no business doing so. The IPCC parallel process hinders exchanges among WGs and the WG I results [on the physical science basis]may not be available to WG III, but will be in due course as there is some staggering of the reports. In the meantime, the Economist report is irresponsible.
So The Economist is, in essence, bending over backwards to manufacture its own data. And after past media mistreatment of the last IPCC report, should we be surprised?
To this point, I would add that the responsible action would be to err on the side of caution, not on the side of laissez faire. In markets, laissez faire often leads to monetary collapses the consequences of which are often recessions. In the case of climate change, laissez faire leads to your civilization, species and large swaths of the natural world in complete wreckage.
We know what the long-term consequences of a certain level of CO2 are. And we know that slow feedbacks might not be so slow under the fast forcing regime we’ve subjected the Earth’s climate to. We also know that we have very little wiggle room for human comfort and prospertity — at best 2 degrees Celsius of warming. So why would we want to, as The Economist does, downplay the problem and risk a dangerous delay of action?
With dangerous and difficult consequences emerging now, we would be insane to follow The Economist’s implicit and falsely comforting advice. Trenberth is right. The report is dreadfully irresponsible as it weakens the case for a necessary and urgently needed response to the harm that is surely coming.