卫星多通道红外信息反演大气可降水业务方法

OPERATIONAL METHOD OF TOTAL PRECIPITABLE WATER RETRIEVED FROM SATELLITE MULTI-CHANNELS’ INFRARED DATA

利用GMS-5多通道资料和MODTRAN辐射传输模式设计并实现了用卫星红外分裂窗通道反演大气可降水的物理反演算法.采用1998年夏季的资料进行了大气可降水反演试验,并使用探空资料对反演结果进行检验,其均方根误差为3.30mm.为了在业务上实现大气可降水物理反演算法,设计了通过利用GMS-5资料、数值预报资料以及RTTOV7快速辐射传输模式的反演大气可降水的物理算法,并用探空资料对反演结果进行检验,其均方根误差为4.09mm.结果表明:RTTOV7快速辐射传输模式的引入,使反演速度有显著的提高,能够满足业务要求.

A physical retrieval method of total precipitable water （TPW） by GMS-5 satellite infrared-split window channels and MODTRAN radiative transfer model was developed. TPW retrieval tests by using data of summer in 1998 were performed and the verification of retrieved results by using radiosonde data was given, whose RMSE was about 3.30mm. To apply a physical retrieval method operationally, a scheme different from one method above was designed, which was performed through GMS-5 multi-infrared channels＇ data and RTTOV7- a fast radiative trasfer model, and whose RMSE was about 4.09mm. The results show that computation cost of the method for RTTOV7 is reduced greatly, which is satisfied for operation purpose.