Satellite Observations of Variations in Northern Hemisphere Seasonal Snow Cover

摘要

Weekly Snow and Ice Charts of the Northern Hemisphere, which had been prepared by the National Earth Satellite Service, were analyzed for the period November 1966 through December 1980. Several snow cover climatologies were created from this digitized archive. Computed monthly snow-cover maps were produced for each month in the study period. Weekly snow-cover-frequency maps were created to illustrate the average frequency of snow cover during the 14-year period for each week. An annual snow-cover-frequency map was created for each snow-cover season. A map illustrating the overall frequency of snow cover for the entire study period was created by averaging all digitized weekly snow-cover charts for the 14-year period. Yearly snow-cover-frequency maps were then compared to the map of overall average snow cover frequency in order to create annual anomaly maps. Weekly snow-cover areas were computed and graphically compared with the average weekly snow cover amounts.