Quantitative Study On Simulation Error Of Microwave Radiative Brightness Temperature With Soil Effective Temperature

In this paper,the soil equivalent temperature was studied at the bright temperature level in passive microwave soil water retrieval.Firstly,the current research status,development trend and existing problems of soil water retrieval in China and abroad are discussed.A brief introduction to the basic principle of soil moisture retrieval with passive microwave and comparative analysis about calculation model are carried out,according to the amount and characteristics of the existing auxiliary data,build a set of applicable to SMOS(Soil Moisture Ocean Salinity)radiation brightness temperature simulation method.(1)For effective soil temperature model error,take error analysis of error sources in size,put forward a new model with error correction by introducing a dynamic temperature layer into soil effective temperature model.The new model can reduce the probability of the big error in soil effective temperature calculation effectively and performs well in the applicability of time and space.(2)Aiming at the data source error of soil effective temperature calculating,the error of effective temperature is estimated by comparing the difference between the measured data source and the model data source.Then,the error estimation of the simulated brightness temperature is carried out by the radiation transfer model.Finally,the effect of the soil effective temperature error was quantitatively analyzed.(3)Through quantitative analysis model error and data sources in soil effective temperature calculation,and then estimates the two error at simulation brightness temperature level.It is concluded that soil effective temperature error can excert a big influence on brightness temperature soil moisture retreval results.This study has certain guiding significance on improvement of soil water retrieval model.