A non-iterative linear retrieval for infrared high-resolutionlimb sounders

[摘要] Currently, most of the high-spectral-resolution infrared limb sounders usesubsets of the recorded spectra (microwindows) in their retrieval schemes toreduce the computing time of rerunning the radiative transfer model. A fastlinear retrieval scheme is described which allows the whole spectralsignature of the target molecule to be used. We determine that pressure andtemperature retrievals can be treated linearly up to a 20% differencebetween the atmospheric state and the linearisation point for a 3% errormargin and up to 10 K "difference" for a 3 K error margin near thestratopause and less than 0.5 K elsewhere. Assuming perfectpTknowledge, CH₄ retrievals can be be treated linearly up to a 20% CH₄concentration "difference" for a 2% error margin. As an example, thistechnique is implemented for the Michelson Interferometer for PassiveAtmospheric Sounding instrument, but it is applicable to any high-resolutionlimb sounder.

[学科分类] 几何与拓扑