Retrieving evaluation of spaceborne microwave hyperspectral sounder for atmospheric profiles in clear-sky

This paper demonstrated the advantages of spaceborne hyperspectral microwave radiometer in retrieving temperature and humidity profiles. Build a forward model using the Atmospheric Radiative Transfer Simulator (ARTS) and input profile datasets from the ECMWF 137 level short range forecasts to calculate simulated brightness temperature. A physical retrieval algorithm (Optimal Estimation Method, OEM) was used to retrieve temperature profiles ranging from 0-40 km and humidity profiles ranging from 0-10 km. The results showed that 10 MHz can more effectively retrieve temperature and humidity profiles. The mean values of root-meansquare error integrated over the height are 0.6096 K (0.6093 K) and 2.6373% (2.7210%) for land (ocean) temperature and relative humidity profiles, respectively. The information content (IC) of different spectral resolutions slightly differs from OEM retrieval results. 10 MHz and 100 MHz spectral resolutions have maximum channel IC for retrieving temperature and humidity profiles, respectively. In conclusion, spaceborne microwave hyperspectral sounder can improve the retrieval accuracy of temperature and humidity profiles by increasing spectral resolution.