HR: 14:00h
AN: U33B-01 INVITED     [Abstracts]
TI: Anticipated Changes in Climate Over North America in the 21st Century
AU: * Mearns, L O
EM: lindam@ucar.edu
AF: National Center for Atmospheric Reseach, P. O. Box 3000 , Boulder, CO 80307, United States
AB: Working Group I of the Intergovernmental Panel on Climate Change, for the first time, makes statements regarding the likelihood of future regional climate changes, in its fourth assessment. Prior to this report, statements were limited to latitude belts or generic statements such as 'mid-continental drying'. I will present these more detailed results for North America, including those for Canada, the United States, and Mexico. The relative strength of the statements made depends on expert judgments of the authors of the chapter on Regional Projections, and considered the following factors: regional results of global climate models, physical understanding of processes governing regional responses, recent historical climate change, and more detailed regional results based on some finer-scale modeling. I primarily discuss the changes in temperature and precipitation and changes in extreme events. It is very likely that all land areas of North America will warm in the 21st century. The warming is likely to be largest in northern regions and in summer in the south-west. Annual mean precipitation is very likely to increase in Canada, and the north-east USA, and is likely to decrease in the south-west. Finally, the value of these types of qualitative statements about regional climate change to stakeholders will be discussed.
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1620 Climate dynamics (0429, 3309)
DE: 1637 Regional climate change
SC: Union [U]
MN: 2007 Joint Assembly