Derivation of snow thickness information on sea ice using in-situ and satellite based multi-frequency polarimetric synthetic aperture radar data

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Considerable attention has focused on the satellite measured decline of sea ice extent in the Arctic Ocean over the past 10+ years. Sea ice makes up approximately 11% of the Earth's surface area and is a critical variable in the global radiation and energy balances and to determining the Earth's response to climate change. The snow cover on sea ice is an important physical variable that plays a central role in mass and energy exchange across the ocean-sea ice-atmosphere interface. Because of the high albedo of snow, the shortwave radiative exchange dominates the sea ice-albedo feedback mechanism during the spring transition season. The onset of spring melt and the eventual formation of liquid water melt ponds on the surface of the sea ice cause rapid decreases in the surface albedo, and as such, cause an increase in the rate of ice melt. Spring melt on Arctic sea ice is highly variable in both space and time and is largely governed by the timing and magnitude of snow thickness on the sea ice prior to sufficient atmospheric warming. Information of snow on sea ice is scarce. This is because of the inherent difficulties in measuring snow distributions remotely and/or the lack of representativeness of High Arctic climate and precipitation reporting stations. Historical data on snow thickness distributions and their relationship to types of sea ice are also rare. Evidence from both observational and modeling studies indicate that snow on sea ice plays a central role in the interaction of visible and microwave energy at the surface and within the volume. My research addresses a number of key questions to understand the inter-relationship between the visible and microwave EM interactions of snow covered sea ice using a combination of surface and satellite based remote sensing data during the spring melt transition period. Observations of snow thickness will be collected annually from both a cold environment laboratory setting and in-situ High Arctic environments coincident with other climate and sea ice measurements along with surface and satellite based remote sensing data for the purpose of quantifying the role snow plays in manifesting sea ice extent and thickness at a variety of spatial and temporal scales.