Northern Great Plains snowpack hydrology from satellite passive microwave observations

The passive microwave emissions of the northern U.S. Great Plains snowpack vary greatly in time and space. An ensemble of snow depth, snow water equivalent, and air temperature observations defines the causes of these changes. Conditions early in the accumulation period set the spatial pattern of the microwave response for the entire winter. For 1997 but not for 1989, the strongest microwave signatures came from the regions containing thinner snowpacks, and there is a strong correlation between the signatures and a cumulative snowpack temperature gradient index