Are recent Arctic climate variations consistent with greenhouse projections?
John Walsh, Department of Atmospheric Sciences, University of Illinois, 105 South Gregory Avenue, Urbana, IL 61801, Phone: 217/333-7521, Fax: 217/244-4393, walsh@atmos.uiuc.edu Control runs and greenhouse simulations from a suite of nine global climate models have provided the basis for an assessment of the climate changes projected for the Arctic as trace gas concentrations increase. Common features of the most of the model projections for the late 21st century are a strong but highly seasonal warming over the Arctic Ocean, a more modest (3ñ6°C) but less seasonal warming over the subarctic land areas, and a summertime increase in subarctic terrestrial precipitation. The models also project a general decrease of sea level pressure over the Arctic and enhanced wind-forcing of ice/ocean outflow to the North Atlantic. The warming is associated with a retreat of sea ice. Observational data for the past half-century show a seasonal warming and an increase of precipitation over the subarctic
