Local and regional albedo observations of arctic first-year sea ice duringmelt ponding

The shortwave surface albedo is a critical climatological parameter for sea ice, especially during the spring melt period when the ice contains a mixt ure of highly reflective (snow) and absorptive (melt ponds) surfaces. Broad band and spectral albedo measurements were made over numerous surface types on first-year sea ice during the melt period in Wellington Channel, Nunavu t during the Collaborative-Interdisciplinary Cryospheric Experiment 1997. A lbedo measurements ranged from 0.75 (moist snow) to 0.21 (dark melt ponds) with many unique intermediate surfaces. Aircraft videography collected thro ughout Wellington Channel and Lancaster Sound was processed to reveal four main surface cover types (wet snow: mixed type, light ponds, and dark ponds ). Surface albedo data were applied to the aircraft observations to upscale surface albedo measurements to regional scales. Aircraft video-derived reg ional albedo (mean = 0.55+/-0.02) were comparable to helicopter and satelli te-derived (Advanced Very High Resolution Radiometer) albedo estimates.