Recently, JIN Xuchen, a master's student in our laboratory, established a salinity remote sensing vector transmission model under non-rainfall conditions. The results were published in the International Journal of Remote Sensing, and the corresponding author is researcher HE Xianqiang.
Based on the vector radiative transfer equation and matrix algorithm, a radiative transfer model based on the L-band that can be used to calculate the outgoing radiation intensity at the top of the atmosphere at different observation angles is proposed and verified. This vector radiative transfer model uses the matrix operator method to describe the impact of wind-induced rough seas on the radiative transfer process (including the emission process and the reflection and scattering of atmospheric downward radiation). Its wave surface slope distribution is based on the Cox-Munk Gaussian Distribution function model; the reflection matrix is obtained by the geometric optics approximation (GO), and the shadowing effect between wave surfaces is taken into account. The model calculation verification results show that the calculation results of the established radiative transfer model are quite consistent with other models (RT4 calm sea surface model, ESA forward modeling model); at the same time, they are consistent with SMOS satellite observation data and ESA forward modeling. A three-way comparison of the model data showed that, with the same input parameters, the horizontal polarization and vertical polarization brightness temperature fields calculated by the model established in this study are consistent with the satellite SMOS measurement data, and the results are better than the ESA forward model. result. At the same time, the model has high computational efficiency. Under the Intel Core 2 computing platform with a core frequency of 2.83GHz, the average computing CPU time for each computing point is about 9 seconds.
Figure 1. Comparison of radiative transfer model predictions, ESA forward model calculations and SMOS detection brightness temperatures in the North Pacific on August 1, 2015. The upper part: the comparison results of the radiative transfer model predictions and the SMOS detection brightness temperature; the lower part: the comparison results of the ESA forward model and the SMOS detection brightness temperature.
Citation: Jin, X., D. Pan, X. He, Y. Bai, P. Shanmugama, F. Gong, Q. Zhu. A vector radiative transfer model for sea-surface salinity retrieval from space: a non-raining case. International Journal of Remote Sensing, 2018.
