用AMSU资料反演西北太平洋海域大气湿度廓线的研究

Retrieving Atmospheric Water Vapor Profiles in the North-West Pacific Using AMSU Measurements

采用快速辐射传输模式RTTOV对AMSU所有通道进行水汽廓线的敏感性分析,并根据模式计算结果逐步剔除相关性小的预报通道,建立两种水汽廓线反演的统计回归模型;之后利用2006年7月NOAA-16卫星AMSU亮温资料,计算不同算法下的反演系数矩阵,回归得出大气水汽廓线。反演廓线经与NCEP廓线比较,得到0600UTC和1800UTC比湿反演的各层偏差(RMS)分别在1.4g/kg及1.7g/kg以内。个例分析发现,反演廓线与NCEP廓线趋势一致;反演比湿场可定位台风云区及水汽供应输送带,具有一定的揭示台风结构的能力。

Radiative transfer model for ATOVS （RTTOV） is used to simulate advanced microwave sounding unit （AMSU） channels＇ sensitivity to water vapor profile ; some of channels are eliminated step by step to establish two retrieving algorithms ; and then retrieving matrixes are calculated and applied to retrieve water vapor profiles from brightness temperatures in July 2006 from AMSU instrument aboard national oceanic and atmospheric administration （NOAA）-16. Compared with reanalysis humidity profiles form national centers for environmental prediction （NCEP）, root mean square （RMS） at 0600UTC and 1800UTC at every single level are within 1.4 g/kg and 1.7 g/kg, respectively. Retrieved water vapor profiles generally agree with NCEP ones; retrieved products can locate the eloud area and water supply of Typhoon; it can describe the structure of Typhoon at some level.