Earth and Atmospheric Sciences, Department of

 

Date of this Version

2001

Comments

Published in Annals of Glaciology (2001) 33: 79-84. Copyright 2001, International Glaciology Society. Used by permission. http://www.igsoc.org/annals/33/

Abstract

The snowmelt-onset date represents an important transitional point in the Arctic surface energy balance, when albedo decreases and energy absorption increases rapidly in response to the appearance of liquid water. Interannual variations in snowmelt onset are likely related to large-scale variations in atmospheric circulation, such as described by the Arctic Oscillation (AO). This research therefore examines the relationship between monthly-averaged AO values and mean annual snowmelt-onset dates over Arctic sea ice in 13 regions, from 1979 to 1998. The objective is to statistically relate variations in mean annual regional snowmelt-onset dates to variations in the AO. Additionally, monthly-averaged 500 hPa heights and 2 m air temperatures are used to illustrate a physical link between snowmelt-onset and a positive AO phase. Regression analyses demonstrate that variations in the AO explain a significant portion of the variations in snowmelt onset in the West Central Arctic, Laptev Sea, East Siberian Sea, Hudson Bay and Baffin Bay. Synoptic analyses suggest earlier (later) than average snowmelt onset occurs where warm (cold) air advection and increased (decreased) cyclonic activity are present.