On the winter evolution of snow thermophysical properties over land-fast first-year sea ice

The geophysical, thermodynamic and dielectric properties of snow are important state variables that are known to be sensitive to Arctic climate variability and change. Given recent observations of changes in the Arctic physical system (Arctic Climate Impact Assessment, 2004), it is important to focus on the processes that give rise to variability in the horizontal, vertical and temporal dimensions of the life-history of snow on sea ice. The objectives in this study are to present these 'state' variables and to investigate the processes that govern variability in the vertical, horizontal and temporal dimension by using a case study over land-fast first-year sea ice for the period December 2003 to June 2004. Results from two sampling areas (thin and thick snowpacks) show that differences in snowpack thickness can substantially change the vertical and temporal evolution of snow properties. During the late fall and early winter (cooling period) we measured no significant changes in the physical properties, except for thin snow-cover salinity, which decreased throughout the period. Fall-snow. desalination was only observed under thin snowpacks with a rate of -0-12 ppt day(-1). Significant changes occurred in the late winter and early spring (warming period), especially for snow grain size. Snow grain kinetic growth of 0.25-0-48 mm(.)day(-1) was measured coincidently with increasing salinity and wetness for both thin and thick snowpacks. Copyright (c) 2006 John Wiley & Sons, Ltd.