Abstract: Based on the radiation transfer equation and a optimized retrieval method proposed by Dennis Chesters et al., this paper describes the general formula of retrieving precipitable water(PW) by the different absorption in the split channel. The feasibility of using radiosonde observations or ground based water vapor radiometer to calibrate the absorption coefficients is researched, and the field of PW is retrieved with the coefficients.

Key words: water vapor, remote sensing, GMS-5, split window

摘要： 从辐射传输方程出发，参照Dennis Chesters等提出的方法，推导了利用水汽在分裂窗两通道吸收的差异来反演水汽总量的一般公式，研究了以探空数据或微波辐射计取得“地面真值”来校准反演公式参数的可行性方法，利用得到的参数反演了同时刻的水汽场。

关键词: 水汽, 遥感, GMS5, 分裂窗