Sun Glint Contamination in ATSR-2 Data: Comparison of Observations and Values Calculated from the Measured 1.6-μm Reflectivities

Abstract The effect of radiation from the sun reflected at the sea surface on the 11- and 12-μm brightness temperatures measured by the Along-Track Scanning Radiometer ATSR-2 has been investigated. An attempt was made to determine its magnitude by comparing nadir-view and forward-view brightness temperature differences in glint and nonglint regions, and the results are compared with theoretical predictions computed by using the 1.6-μm reflectivity data. Atmospheric absorption and the polarization sensitivity of the instrument have been fully taken into account. The results show that temperature increases of a few tens of millikelvins are possible even over the open ocean, and that they correlate well with the measured 1.6-μm reflectivity values. A scheme for correcting the sun glint contamination is proposed.

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