Spatial and temporal variability of satellite-derived cloud and surface characteristics during FIRE-ACE

Advanced very high resolution radiometer (AVHRR) products calculated for th e western Arctic for April-July 1998 are used to investigate spatial, tempo ral, and regional patterns and variability in energy budget parameters asso ciated with ocean-ice-atmosphere interactions over the Arctic Ocean during the Surface Heat Budget of the Arctic Ocean (SHEBA) project and the First I SCCP (Internatonal Satellite Cloud Climatology Project) Regional Experiment - Arctic Cloud Experiment (FIRE-ACE). The AVHRR-derived parameters include cloud fraction, clear-sky and all-sky skin temperature and broadband albed o, upwelling and downwelling shortwave and longwave radiation, cloud top pr essure and temperature, and cloud optical depth. The remotely sensed produc ts generally agree well with field observations at the SHEBA site, which in turn is shown to be representative of a surrounding region comparable in s ize to a climate-model grid cell. Time series of products for other locatio ns in the western Arctic illustrate the magnitude of spatial variability du ring the study period and provide spatial and temporal detail useful for st udying regional processes. The data illustrate the progression of reduction in cloud cover, albedo decrease, and the considerable heating of the open ocean associated with the anomalous decrease in sea ice cover in the easter n Beaufort Sea that be.-an in late spring. Above-freezing temperatures are also recorded within the ice pack, suggesting warming of the open water are as within the ice cover,