Cloud radiative forcing over the Beaufort Sea and north slope of Alaska

The north slope of Alaska provides a unique opportunity to observe differences in surface cloud radiative forcing over land, snow, ice, and sea. Data collected during late summer 2000 from the Atmospheric Radiation Measurement (ARM) site at Barrow are compared with coincident shipboard measurements from the USCGC Polar Star and co-located remotely-sensed data, including MODIS, AVHRR, TOVS, SeaWiFS, and SSM/I. This combined data set is then used to evaluate the accuracy of several downwelling radiative parameterizations and test the sensitivity of radiative transfer models to changes in surface type, aerosol loading, cloud layering, and cloud microphysics. Further comparison with the SHEBA (Surface Heat Budget of the Arctic) data set underlines the considerable seasonal and interannual variability that defines the Alaskan Beaufort Coast.