Sea surface salinity observed from the HY-2A satellite
DOI:
https://doi.org/10.18063/SOM.2017.01.004Keywords:
Sea surface salinity, microwave radiometer, HY-2A satellite, SMOS, Aquarius, emissivity modelAbstract
Motivated by the shortcomings of radio frequency interferences (RFI) associated with the spaceborne L-band radiometers near the Northwest Pacific and previous study near the Amazon plume, this study presents a sea surface salinity (SSS) retrieval algorithm from the microwave radiometer onboard the HY-2A satellite. The SSS signal is improved by differentiating the reflectance between the C and X band. A reflectance calibration method is proposed by using a combination of radiative transfer model (RTM) and the Klein-Swift emissivity model. Evaluations of the retrieved SSS from the HY-2A satellite indicate that the root mean square error (RMSE) is about 0.35 psu on 0.5 degree grid spacing and monthly time scale which is comparable to the accuracy of SMOS and Aquarius-SAC/D satellites.References
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