Climate agency accused of cooling on global warming as new report lowers predicted temperature increase
Joseph Brean | 13/09/15 | Last Updated: 13/09/16 8:59 AM ET
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AP Photo/Mikhail MetzelA greenpeace activist dressed as a polar bear sits on a wooden block of ice on the Moskva River protesting against plans of oil companies' drilling in the Arctic, with the Kremlin wall in the background, in Moscow, Russia, Monday, April 1, 2013.
As it prepares to present its first report in six years to the world’s governments, the Intergovernmental Panel on Climate Change has lowered the range of predicted global warming by half a degree celsius, leading to accusations of a climb-down from earlier, more dire forecasts.
The subtle drop, which suggests a doubling of atmospheric carbon would increase mean global temperatures by between 1.5 and 4.5 degrees celsius, rather than the earlier range of between 2 and 4.5 degrees, is included in a confidential summary for policymakers obtained by the National Post.
There is a broad agreement among countries, derived largely from the IPCC, that warming must be kept lower than 2 degrees in order to avert the most serious consequences. This latest range is the first to suggest that threshold might not be crossed.
The adjusted prediction follows a more drastic backtracking by the British Met Office, which this year lowered by 20% its previous prediction of how much hotter the coming few years will be than the long-term average since 1971. Both reflect efforts by climate scientists to reconcile the predictions of computer models with the observed so-called “pause” in global warming, which apparently stalled in 1998 and has yet to resume. This unexplained trend has been a headache for policymakers, many of whom came to the climate file during the era of clear-eyed alarmism driven largely by Al Gore’s film, An Inconvenient Truth.
With a major global meeting next week in Stockholm, at which the IPCC’s final report is to be released and questions debated by government negotiators, and with other geoplitical issues crowding climate off the agenda, this minor adjustment could cause big problems.
Matt Ridley, a scientist and journalist who is also a member of the British House of Lords, wrote in a Wall Street Journal essay on the weekend that the IPCC “dials back the alarm” with a “clear” downward adjustment of its predictions.
“Admittedly, the change is small, and because of changing definitions, it is not easy to compare the two reports, but retreat it is,” he wrote. “It is significant because it points to the very real possibility that, over the next several generations, the overall effect of climate change will be positive for humankind and the planet.”
Some scientists, however, see the new report as a validation and slight refinement of the previous one, from 2007.
Andrew Weaver, a climate scientist who co-authored the relevant chapter of the IPCC’s full report, said this is a misinterpretation, “an incorrect, qualitative interpretation of what the science is saying.”
It’s essentially more of the same, with a little more certainty
He said the chapter he co-wrote states: “Despite considerable advances in climate models and in understanding and quantifying climate feedbacks, the assessed literature still supports the conclusion from [the previous IPCC report] that climate sensitivity is likely in the range 2–4.5°C, and very likely above 1.5°C.”
“What we’ve learned since 2007 is not a lot of new stuff. It’s basically underscoring with greater certainty what we’ve already said,” said Prof. Weaver, a British Columbia Green Party MLA on political leave from the University of Victoria. “To capture it in a sound bite, it’s essentially more of the same, with a little more certainty…. Scientists have done their job. Now it’s time for policymakers and politicians to do theirs if we as a society want to deal with this problem. Here we are, in 2013, with another massive report. It’s just saying the same thing.”
It is true that little has changed since the previous report, and the grandest conclusions remain worrying. Each of the last three decades has been warmer than all preceding decades since 1850, it states, and the first decade of the 21st century was the warmest. 1983-2012 is said to be “very likely” the warmest 30-year period of the last 800 years, and “likely” the warmest in 1400 years.
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Others disagree that this represents progress toward accuracy. Unable to explain its failure to predict the current “pause” in warming, the IPCC “appears determined to double down and claim even more confidence than ever in their models,” said Ross McKitrick, a University of Guelph economist who was instrumental in criticizing and eventually undermining the famous “hockey stick” graph of rising global temperatures.
“It’s possible the government negotiations will move them towards a more credible statement, but the problem is the negotiators at this point are from national environment ministries who all have a vested interest in promoting the climate scare,” Prof. McKitrick said. “So I don’t hold out any hope that a realistic document will emerge from Stockholm.”
The draft summary document, dated in June and marked “Do Not Cite, Quote or Distribute,” is based on “new evidence of past and projected future climate change based on many independent scientific analyses ranging from observations of the climate system, paleoclimate archives, theoretical studies of climate processes and simulations using climate models.”
It lists two Canadians among the authors, Environment Canada scientists Nathan Gillett and Gregory Flato.
I don’t hold out any hope that a realistic document will emerge
Mr. Gillett declined to comment without approval from Environment Canada, which did not reply to a request to interview either scientist by press time Sunday.
Bruce Pardy, an expert on environmental law and governance at Queen’s University, said the IPCC “has run into difficulty again. That is not surprising, since the IPCC claims to be a scientific body that in reality is an intensely political organization.”
He said their mandate to offer policymakers a consensus view from scientists was “asking for trouble” all along, because science is not done by consensus, “but requires independence, disagreement and debate. Climate science is notoriously uncertain…. Moreover, the IPCC appears to believe that it has a role in developing or influencing policy, which is not a scientific matter. Policy depends on values. Values are not scientific. When scientists take positions on policy, they forfeit their claim of being objective observers. Instead, they reflect their own preferences, and can no longer be relied upon as neutral sources of facts.”
Gordon McBean, a leading Canadian climatologist at Western University and president-elect of the International Council for Science, criticized a report on the adjustment in the British Mail on Sunday newspaper for “comparing two different time periods.”
“Yes, the rate of warming over the past decade to fifteen years has decreased,” he said, but if you adjust for the effects of El Nino (the southern hemisphere oscillation), the trend is more or less what the previous IPCC report predicted.
“It is unfortunate that certain media will misquote or emphasize certain issues in order to convey their pre-conceived message,” he said. “In Canada, the Harper Government clearly has no intention of really doing anything on greenhouse gas emissions so they will use these stories to justify their inaction.”
Chris Fletcher, an expert on climate modelling and analysis at the University of Waterloo, said “the real focus should be on the fact that the models continue to predict a ‘likely’ global warming over the coming century in the range 1-2.5 C, with more to come in future centuries. That is a very significant climate change in a [geologically] short period of time, and it is directly attributable to human activity. That alone is a big story.” |
