Airborne springtime IOP measurements of radiative exchange and albedos in the Barrow, Alaska, region and comparisons to growing season results

On April 8, 1999, at approximately local solar noon, airborne measurements of longwave and shortwave radiation were conducted in the Barrow, Alaska, r egion. Over the pack ice (100 km north of Point Barrow), albedo averaged 0. 83, net radiation flux (average 32.4 W m(-2)) was into the surface, and sur face temperatures were positively correlated to observed cloudiness and mea sured sky temperatures. Over the coastal "fast" ice and tundra, albedo aver aged 0.90, net radiation flux (average 2.7 W m(-2)) was out of the surface, and surface temperatures were not significantly correlated to observed clo udiness or measured sky temperatures. Albedo was not a significant function of observed variation in cloudiness or sky temperature but may have been a ffected by measurable snowfall the previous day at Barrow. Compared to grow ing season albedos, springtime albedos had lower coefficients of variation.