Retrieval of Emissivity and Temperature Profile in Polar Regions

Polar regions are composed of different surface types, e.g., open water, land ice and different types of sea ice. As a consequence the retrieval of near surface atmospheric parameters (temperature, humidity etc..) is restricted due to the high and highly variable surface emissivity except for open water. The surface emissivities are retrieved using the brightness temperatures at window channels of the cross-track scanning advanced microwave sounding unit (AMSU) satellite radiometer. The emissivities are practically constant up to local zenith angles of 45deg. Comparison of temperature profiles retrieved from AMSU is done with the radiosonde measurements. The root mean square deviations from the measurements is 2 K. Near the surface it increases up to 6 K.