温室气体监测仪星上光谱定标及不确定度分析

On-Orbit Spectral Calibration and Uncertainty Analysis of Greenhouse Gases Monitoring Instrument

大气主要温室气体监测仪(greenhouse gases monitoring instrument,GMI)采用空间外差干涉技术,能有效探测759~2058 nm波段大气高分辨率吸收光谱信息.星上定标是GMI光谱图像数据定量化应用的基础,在阐述了GMI成像和光谱定标原理的基础上,探讨了星上光谱定标方法,确定了外部光源特征谱线法的星上光谱定标方案。通过对模拟数据的计算,进一步分析了定标不确定度,得出星上光谱定标不确定度为0.030 nm.定标结果显示定标不确定度主要受定标光源不确定度,以及回归不确定度影响,该方法满足仪器的定标要求,为大气主要温室气体的定量化反演提供了依据.

Greenhouse gases monitoring instrument （GMI） uses spatial heterodyne interference technology which can effectively detect atmospheric high-resolution absorption spectra during 759~2058 nm. And the calibration is the base of GMI spectral image data quantitative application. Based on the principle of GMI imaging and spectral calibration, the methods of on-orbit spectral calibration are discussed, and spectral cali- bration scheme of the external light source characteristic spectral is presented. Through the calculation of the simulation data, the uncertainty of calibration is further analyzed, and the uncertainty of on-orbit the spectral calibration is 0.030 nm. The calibration results show that the calibration uncertainty is mainly affected by the light source calibration uncertainty and regression uncertainty. The method meets the calibration requirements of the instrument and provides the basis for quantitative inversion of atmospheric main greenhouse gases.