On Forward Modeling And Parameter-retrieval Of Space Borne Atmospheric Remote Sensing Based On Microwave Radiative Transfer Model

The aim of atmospheric radiative transfer(RT)modeling is to understand the three kind of interactions between microwave radiation and the atmospheric environment,to build models,and to quantitatively calculate the intensity of radiation field.This research on how microwave radiation interacts with the atmosphere may contribute to our understanding of the relationship between physical parameters of the atmosphere,the ground surface,the sea surface together with the ice surface and the transfer of radiative energy,which makes this study an essential support for atmospheric remote sensing.Thanks to the complexity of multi-scattering effect of hydrometers,existing RT models perform badly in strong scattering situations such as rain and snow,which hampers the utilization of data collected in such areas.As a result,the better modeling of atmospheric scattering effect and the improvement of microwave RT model becomes one of the hot spots of atmospheric remote sensing.This paper reviewed the related work on atmospheric RT modeling and focused on its latest developments,summarized the expression of scattering based RT problem and the formulation of RT equation,studied the numerical solution of RT equation based on discrete ordinate method and multi-layer adding.By studying on the latest work on scattering based RT modeling,the forward modeling of observation was implemented to calculate the simulated brightness temperature of satellite based microwave radiometer.With the help of this forward model,performances of DOTLRT and RTTOV were evaluated on real observation data.Some more researches were conducted on the retrieval of atmospheric parameters,artificial neural network was trained on forward simulated data of RT model and the temperature and humidity profile,along with integrated cloud liquid water and integrated rain were successfully retrieved.By comparing the retrieved results of satellite-based microwave radiometer to that of ground-based microwave radiometer,the practicability of NN retrieval method was confirmed.