PATH-LENGTH VARIATIONS CAUSED BY ATMOSPHERIC WATER-VAPOR AND THEIR EFFECTS ON THE MEASUREMENT OF MESOSCALE OCEAN CIRCULATION FEATURES BY A RADAR ALTIMETER

Scanning multichannel microwave radiometer (SMMR) data from the entire 3-month lifetime of the Seasat satellite are used to estimate water vapor path length corrections and to assess the probability that water vapor will significantly degrade the interpretation of Geosat altimeter data. Cumulative distributions describing water vapor statistics for a variety of spatial scales and in specific geographical regions, as well as the entire globe, are presented. It is demonstrated that FNOC-derived water vapor path lengths, although providing a good mean correction, will not serve to compensate for small horizontal scale changes in water vapor. -from Author