Fairbanks, Alaska -- University of Alaska Fairbanks climate scientist John Walsh is among the lead authors of the second volume of the Fourth Assessment Report from the Intergovernmental Panel on Climate Change.
The volume, "Impacts, Adaptation and Vulnerability," analyzes how climate change is affecting natural and human systems. It also examines future effects of climate change and how adaptation can reduce those effects. Walsh was a lead author of the chapter on polar regions.
Walsh said the chapter drew on the findings of the 2004 Arctic Climate Impact Assessment report. "We tried to update it with some impact issues that seemed to be more prominent now than several years ago," he said, noting the increased vegetation density, coastal erosion and sea ice retreat in the arctic region and the possible changes to the flow rates and discharge of the Antarctic ice sheet.
"The impacts are apparent already and, in many ways, the Arctic is more vulnerable than the rest of the world in terms of its ecosystems and its peoples," Walsh said. "As far as the Antarctic goes, there are no people, but there are parts of the marine ecosystem, especially the krill and the marine mammals, that are vulnerable to climate change."
He said the chapter also points out some of the possible benefits to the Arctic of a warmer climate, including reduced heating costs, increased agriculture and forestry opportunities, and improved access for offshore resource development and shipping.
Unlike the first volume of the report, which detailed the physical science behind climate change, the second volume focuses exclusively on its current and potential effects. That made writing the report a challenge, since authors had to consider future social, technological and economic changes, as well as the uncertainties of climate prediction, Walsh said. "All of those things factor into the impacts, vulnerabilities and adaptations, and the non-climate factors are even more difficult to assess than the scenarios of climate change."
Walsh is a president’s professor of climate change and director of the Center for Global Change and Arctic System Research at the UAF International Arctic Research Center.
The IPCC plans to release the final two volumes of the Fourth Assessment Report later this year. The third volume, "Mitigation of Climate Change," is slated for release in early May, The fourth volume, a synthesis report, is scheduled to be approved at the 27th Session of the IPCC in November in Spain.
The World Meteorological Organization and the United Nations Environment Programme formed the IPCC in 1988. Its role is to assess, on a comprehensive, objective, open and transparent basis, scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation.
ON THE WEB: www.ipcc.ch/