Airborne Measurement of Snow Thickness over Sea Ice

Snow cover on sea ice plays an important role in the climate of the polar regions. Snow on the sea ice reduces the heat exchange between the ocean and the atmosphere by its high albedo and low thermal conductivity. The lower the albedo, the less solar energy is reflected back into the atmosphere. Data on the extent and thickness of snow cover is needed to understand the condition and future behavior of sea ice. Remote sensing is a commonly used means of observing snow cover over sea ice. The advanced microwave scanning radiometer (AMSR-E) is one instrument for accomplishing this objective. To validate measurements made by AMSR-E, the University of Kansas developed an ultrawideband frequency-modulated continuouswave (FM-CW) airborne radar to measure snow thickness over sea ice. The University of Kansas tested their radar system on board the NASA P-3 aircraft during the NASA Arctic 2006 Field Campaign over the Alaskan coastal region. The objective of this field campaign was to acquire a comprehensive data set that will enable validation of the snow thickness retrieval algorithm AMSR-E passive microwave sensor measurements on board NASA's AQUA satellite. This paper contains the preliminary results of resolving the air/snow interface and the snow/ice interface.