North American and Eurasian snow cover co-variability

Abstract

The extent of snow cover over the Northern Hemisphere landmasses was computed over the period January 1973 to May 1996 using monthly data derived from the NOAA/NESDIS data set. A comparison has been made of the variability over the North American and Eurasian continents. We have found there to be significant memory in anomalies of snow cover for up to 3 months. We have also identified significant temporal associations between snow variability over North America and Eurasia, and these tended to be larger when North America was leading. Some suggestions for the link in variability are made. We have made a similar calculation using passive microwave sea-ice data from January 1979 to July 1995 in order to determine whether there is any link between the variability of sea-ice and that of continental snow cover. Over the period we have examined, there appeared to be a moderate connection between North American snow and Arctic sea-ice but no connection for Eurasia.