9320786 ROBINSON Physical geographers, climatologists, and other scientists recently have come to understand the critical and highly variable role that snow cover plays in the global climate system. Recent research has gathered data over the last century from satellite images and ground station records. This research also has advanced analyses of relationships between the extent of snow cover and surface air temperatures. This collaborative research project will continue this line of inquiry by expanding the study of snow kinematics to include data on snow depths and by extending analyses to consider associations among snow cover and depth and other near-surface atmospheric conditions. Data will continue to be acquired from satellite and surface-based sources in order to better explore spatial and temporal patterns of the extent and depth of terrestrial snow cover throughout the Northern Hemisphere. The analyses also will identify and diagnose sensitivities of near-surface atmospheric variables to variations in snow cover across a range of spatial and temporal scales. The investigators also will test the capabilities of different general-circulation climate models to simulate observed patterns of snow cover and its relationships with other variables. This research will extend a productive line of inquiry on an important topic. The data-collection activities will expand a database of Northern Hemisphere snow cover over the last century, further improving a resource that already has been used by other researchers. These activities are complemented by analyses of relationships between snow cover and a range of atmospheric variables. More complete understandings of these relationships should advance general knowledge and help refine meteorological forecasting techniques. The evaluation of general-circulation models should also prove useful in assessing the possible consequences of continued increases in atmospheric carbon dioxide and other forms of global environmental change. ***
