GOASEX Workshop Results from the Seasat-1 Scanning Multichannel Microwave Radiometer

The results for the SEASAT-1 Scanning Multichannel Microwave Radiometer (SMMR) from the Gulf of Alaska Seasat Experiment (GOASEX) Workshop held 22-26 January 1979 at JPL are quite encouraging, especially when the immaturity of all the data processing algorithms is considered. Specifically, for open ocean cells of highest quality surface truth in which no algorithmic rain is indicated, wind determinations exhibit standard deviations of about 3 m/sec about a bias near 1.5 m/sec. Highest quality surface truth estimates are probably accurate to m/sec. This strongly suggests that the SEASAT-1 SMMR design goal of m/sec wind speed measurement accuracy can be-reached. Possibly only somewhat higher quality surface truth data combined with algorithm refinement and recalibration are required. The SST determination had cold biases of C and standard deviations about the bias of approximately C. The stability of the SMMR temperature estimates over the nine day period 16-25 September 1978 investigated in the GOASEX workshop provides encouraging evidence that the instrument and particularly one of the algorithms are operating well, under a variety of changing meteorological conditions. Furthermore, the entry estimates on the amount of rain that would invalidate SST determination appear somewhat conservative. The algorithms determined integrated atmospheric water vapor, altimeter path length corrections, and SASS attenuation estimates that are quite consistent with the limited surface truth provided by a set of five radiosonde ascents over weather station PAPA and R/V Oceanographer. The rain rate determinations are consistent with the observed weather, but integrated liquid water determinations in many cells are physically uninterprettable (small but negative). The biases in wind speed and SST determination had some variations with S/C pass and with location in swath. This could be attributable to problems in decou- - pling horizontal and vertical polarizations that were uncovered during the workshop.