Method for Retrieval of the HDO/H2O Ratio Vertical Profile in the Atmosphere from Satellite Spectra Simultaneously Measured in Thermal and Near-IR Ranges

An original method is suggested for solving the inverse problem of hyperspectral satellite sounding of the atmosphere for retrieving the HDO/H2O ratio vertical profile in the atmosphere with simultaneous inversion of thermal and near-IR spectra. A computational experiment was performed to retrieve the vertical profile of the relative content of the HDO isotopologue in atmospheric water vapor from high-resolution spectra simulated with parameters of the TANSO-FTS spectrometer onboard the GOSAT-2 satellite. The inverse problem was solved by the optimal estimation method with simultaneous inversion of thermal and near-IR spectra. The output data of the isotopic version of the ECHAM6-wiso atmospheric general circulation model were used as an a priori statistical set of water vapor isotopologue vertical profiles.