Land Intercalibration and Drift Monitoring of MWR Radiometer on Board SAC-D/Aquarius

CINTIA BRUSCANTINI; MARTÍN MAAS; FRANCISCO GRINGS; HAYDEE KARSZENBAUM

IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2015

1939-1404

?The microwave radiometer (MWR) on board theSAC-D/Aquarius mission is a Dicke radiometer operating at 23.8(H-Pol) and 36.5 GHz (H/V-Pol), which can provide ancillary datafor the various retrievals to be performed with Aquarius regardingocean and land applications. In this study, we report calibrationresults obtained by a land cross-calibration between Windsatand MWR. Moreover, MWR drifts were monitored using vicariouscold methodology. Results were generated for the 2011?2012period using version V5.0 S of MWR data. MWR and Windsatcross-calibration was carried out over selected homogeneous targetswhich include tropical and boreal forests, desert, grassland,and the Sahel. As a result, biases were identified and correctionswere proposed. Drifts in MWR observations were identified byimplementing the vicarious cold method, which is a statisticalapproach that estimates the coldest value of the brightness temperature(Tb) (over ocean) histogram. Time series of such coldvalues are closely related to drifts in the instrument. In general,it was observed that MWR drifts tend to stabilize within 1 Kafter June 2012, when the software of the on-board computer wasupdated.