BERN, Switzerland, Sept. 27 (UPI) —
International scientists are 95 percent sure human activities are the main cause of global warming, an U.N. report to be released Friday is expected to say.
The report by the Nobel Prize-winning U.N. Intergovernmental Panel on Climate Change is expected to say human influence — notably the burning of fossil fuels — is "extremely likely" to be the culprit, up from "very likely" in the panel’s 2007 assessment.
"Extremely likely" means scientists have at least a 95 percent confidence level in the findings. "Very likely" points to a confidence level of at least 90 percent.
The panel’s confidence level was 66 percent in 2001 and slightly more than 50 percent in 1995.
The widespread expectation about the content of Friday’s report is based on a report draft leaked to the media in August.
Scientists have been going through the report as late as Thursday to reach agreement on conclusions and wording, one of the report’s authors told British newspaper The Daily Telegraph.
Friday’s report is the culmination of studies by more than 850 scientists from 85 countries whose work was compiled over three years by some 250 authors from 39 countries, CNN said. That work was reviewed by more than 1,000 experts, the network said.
The report is expected to be the first of three released by the panel over six months.
The first is to focus on the physical science behind climate change. The second, to be released in March, is expected to cover climate change "impacts and vulnerabilities." The third, in April, is expected to focus on ways of responding to and mitigating the change.
Among the topics expected to be included in Friday’s report is the loss of sea ice.
It is also expected to say climate change will weaken the Gulf Stream 20 percent to 44 percent by the end of the century.
The Gulf Stream is a powerful, warm and swift Atlantic Ocean current that originates in Florida and follows the eastern U.S. shoreline north to Canada’s Newfoundland and Labrador before crossing the Atlantic Ocean to Europe.
This could cool and disrupt weather patterns on the U.S. East Coast. It could do the same in England, the Telegraph said.
Scientists warn the cooling could mask global warming’s effects, the newspaper said.
Despite the IPCC report’s extensive breadth and review, skeptics have claimed the panel’s main purpose is to support the idea of human-caused climate change while ignoring opposing research.
On the other side of the argument, climate change activists, and many climate scientists, say the panel’s consensus-seeking policy ends up producing conclusions and estimates that are too conservative.
Another critique is that a report this comprehensive, requiring such a lengthy approval process, is already outdated.