Satellite-Derived Maps of Snow Cover Frequency for the Northern Hemisphere

Abstract

A satellite imagery-based Northern Hemisphere snow cover data archive was mapped for the period 1966–84: The maps were digitized in order to create the first hemispheric, spatially data-continuous climatologies of snow cover. Annual and monthly climatologies were created and compared to several standard or frequently referenced climatologies. Results of this analysis indicate that the satellite-based climatology provides a much more detailed climatology for the higher latitude and highland regions of the Northern Hemisphere. The satellite imagery-based maps, when compared to the historical snow cover climatologies, indicated more extensive high-latitude snow cover concurrent with a northward shift in the southern extent of the climatological snow cover, this results in a narrower snow-transition zone.