Influence of Oceanic Parameters on Aquarius L-Band Sea Surface Emissivity

Abstract

A systematic assessment of the effects of various oceanic parameters on sea surface emissivity based on Aquarius measurements is presented in this paper. The results show that the influence of wind speed on wind-driven emissivity increment ΔE is most significant. The magnitude of change in ΔE related to W can be as large as 8.02 K. The wind direction signal has been found to be small at low and moderate wind speeds, whereas it is significant at high wind speed and reaches a maximum of 1.37 K at 22.5 m/s. The influence of backscatter under HH polarization is notable and as large as, or larger than backscatter under VV polarization. The effects of the SST and SWH on ΔE are relatively small with the max magnitude of change in ΔE of 0.86 K and 0.49 K, respectively. Furthermore, strong correlations are found among wind speed, microwave backscatter under VV and HH polarization, which are higher than ninety percent. Therefore, the decorrelation of oceanic parameters is recommended to be considered in the process of emissivity correction because of the high correlations among oceanic parameters.