Scientists Left Uneasy by Changes to Climate Report
Deletions made during an all-night editing session on a draft report on global warming released in Brussels, Belgium, on Friday have left some scientists uneasy.The fourth assessment report of the Intergovernmental Panel on Climate Change warned that rising Earth temperatures raises the specter of widespread floods, water shortages and species extinction.
But some key findings in the report had to be changed in order to obtain the required consensus agreement from the more than 120 nations taking part.
"We believe that this was unprecedented in the history of the IPCC since 1988, and was an ugly and damaging development. To our knowledge there have been no similar acts in the history of the IPCC," the environmental group Greenpeace said.
Changes in a 23-page Summary for Policymakers on climate change impacts, adaptation and vulnerability omitted a scenario showing the potential impact of policy on climate change and toned down the level of confidence that regional climate changes are affecting natural systems.
The authors of the report had wanted to assert that "based on observational evidence from all continents and most oceans, there is very high confidence that many natural systems are being affected by regional climate changes, particularly temperature increases," according to Joel Smith, a drafting author and former deputy director of the Environmental Protection Agency.
Very high confidence means nine out of 10 chances. China and Saudi Arabia wanted the language downgraded to "high confidence" (eight out of 10 chances).
The three authors proposed putting "very high confidence" into a footnote, Smith said in an interview from Brussels.
But ultimately the United States led a group to work out a solution - removing the reference to confidence level and omitting a footnote.
"It was almost splitting hairs," Smith said.
Although a lay person would regard eight out of 10 "pretty high," he said, the authors "did not appreciate the fact that countries were trying to tell them how to interpret science. My sympathies were with the authors."
China is a large user of coal and Saudi Arabia is a major producer of oil - two prime sources of carbon dioxide, the leading greenhouse gas.
Smith said the scientific data behind the report are extensively peer-reviewed but governments involved in the IPCC have much power because they "buy in" to the assessment report.
"At the end, this isn't just about science. This is ultimately about policy," he said.
A technical report to be issued later would include the authors' language, Smith noted.
Smith also said some governments had objected to "stabilization scenarios" - the impact that policy could have on climate - and emissions scenarios showing how temperatures would rise under different greenhouse gas emission paths in the 21st century.
Some governments said the stabilization scenarios were not appropriate for the working group, although the IPCC had requested the information, Smith said.
The objection to emissions scenarios, he said, left scientists "somewhat befuddled" over "why you wouldn't want to show how much warming you would have over the century for no climate policy."
Also left out of the report last week was a table on regional impacts. Smith said he and other scientists were asked to work with the governments to review the draft but the late-night effort was so complicated that there was no time to accomplish it.
Smith said that during his participation in an earlier assessment report, authors had had a stronger voice in negotiations.
This year, he said, battles over wording had been stronger and the consensus process had resulted in a statement that the authors did not feel comfortable with.
Source: CQ Green Sheets
© 2007 Congressional Quarterly Inc.