Historical variability in Northern Hetnisphere spring snow-covered area

Observed and reconstructed snow-cover duration data from stat ions covering southern Canada, the Great Plains, the former Soviet Union and China were used to reconstruct spring snow-covered area over North America (NA) and Eurasia from 1915 to 1985. A combination o[nine regions from NA and five from Euras ia were able to explain 81 % and 67%, respectively, of the variance in satellite-derived spr ing SI10Wcovered area (SCA ) [or each continent. The resu lts suggested spring SCA had decreased significan tl y in Eurasia this century, but there was no evidence ofa simil ar long-term decrease in NA spring SCA. Considerable caution should be used when interpreting these results because of the short period of ca libration, and because of the less-than-optimal distribution of station data. :'Ironetheless, the reconstructed results are cons istent with observed spring-temperature trends, which show a significant increase over Eurasia, but none over NA.