Variability of northern hemisphere spring snowmelt dates using the AVHRR polar pathfinder snow cover during 1982-2004

Abstract

A new daily 5 km resolution Northern Hemisphere (NH) snow cover product derived from AVHRR Polar Pathfinder data (APP), available from 1982 to 2004, has enabled the investigation of the variability of the spring snowmelt dates at continental and hemispheric scales in association with variability of circumpolar climate parameters. Continentally averaged and latitude band averaged snowmelt date time series were analyzed together with melting season temperatures, preceding winter precipitation and atmospheric circulations. Snowmelt dates over northern Eurasia and North America did not show a statistically significant trend but rather a strong interannual variability related to anomalously large-scale atmospheric circulations. The average North American snowmelt date was observed to be later than that of northern Eurasia except the year of 1998. Snowmelt dates co-varied on interannual timescales between North America and the northern Eurasia before 1998. After 1998, snowmelt dates between the two continents are poorly related. The change in regime may be associated with the interdecadal coupling in climate variability between North pacific and North Atlantic. Finally, the less contribution in interannual variability of snow factor to snow albedo feedback was explained by analyzing seasonal snow-temperature sensitivity regions. © 2010 Springer Science+Business Media B.V.