Characterize the uncertainties in the use of radiosonde data for satellite atmospheric sounding validation

Balloon-borne radiosonde observations (RAOBs) are commonly used as targets in the calibration/validation (cal/val) of satellite infrared sounder atmospheric temperature and water vapor retrievals. Uncertainties, however, are present in this cal/val approach arising from the different spatial and temporal characteristics including mismatch of the collocated RAOB and satellite data, the RAOB measurement error, and inconsistencies between the RAOB and satellite sounding vertical resolution. Analysis to quantify these uncertainty components using a large sample of collocations of global conventional RAOBs with satellite data including GNSSRO data combined with a relatively small number of collocations of error-traceable GRUAN and dedicated RAOB (i.e., synchronized with satellite overpass) with satellite data, is presented.