A Parameterized Multi-Frequency-Polarization Surface Emission Model
多频率多极化地表辐射参数化模型

This study develops a parameterized bare surface emission model for the applications in analyses of the passive microwave satellite measurements from the Advanced Microwave Scanning Radiometer-Earth Observing System(AMSR-E).We first evaluated the capability of the Advanced Integral Equation Model(AIEM) in simulating wide band and high incidence surface emission signals in comparison with the INRA's field experimental data obtained in 1993.The evaluation results showed a very good agreement.With the confirmed confidence,we generated a bare surface emission database for a wide range of surface dielectric and roughness properties under AMSR-E sensor configurations using the AIEM model.Through the evaluations of the commonly used semi-empirical models with both the AIEM simulated and the field experimental data,we developed a parameterized multi-frequency-polarization surface emission model-the Q_p model.This model relates the effects of the surface roughness on the emission signals through the roughness variable Q_p at the polarization p.The Q_p can be simply described as a single surface roughness property-the ratio of the surface rms.height and the correlation length.The comparison of the emissivity simulations by the Q_p and AIEM models indicated that the absolute error is extremely small at the magnitude of 10~(-3).The newly developed surface emission model should be very useful in modeling,improving our understanding,analyses,and predictions of the AMSR-E measurements.