AIRS辐射亮温在中亚地区的偏差分析及适用性  

Bias analysis and applicability evaluation of the atmospheric infrared sounder(AIRS)radiance in Central Asia

作　　者：马玉芬[1,2] 李如琦 张萌 买买提艾力·买买提依明 张广兴[1,2] MA Yufen;LI Ruqi;ZHANG Meng;Ali Mamtimin;ZHANG Guangxing(Institute of Desert Meteorology,CMA,Urumqi 830002,Xinjiang,China;Central Asia Atmospheric Science Research Center,Urumqi 830002,Xinjiang,China;Xinjiang Meteorological Observatory,Urumqi 830002,Xinjiang,China)

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002 [2]中亚大气科学研究中心,新疆乌鲁木齐830002 [3]新疆气象台,新疆乌鲁木齐830002

出　　处：《干旱区研究》2021年第1期12-21,共10页Arid Zone Research

基　　金：国家自然科学基金(41805075,41875023);国家重点研发计划项目(2018YFC1507105)资助。

摘　　要：中亚地区常规观测站点稀少,需借助星载高光谱AIRS资料分析出该地区数值预报最优初始场。以CRTM中输入探空模拟出的AIRS辐射亮温为参考值,分析了AIRS观测亮温偏差,并评估了AIRS卫星资料在中亚数值天气预报业务系统中的适用性。结果表明:(1)各通道模拟所选站点上空亮温最大正偏差的平均值约为3.3 K,最大负偏差的绝对值约为2.6 K。(2)多个站点平均的AIRS观测辐射亮温整体略高于模拟亮温,其概率密度分布比单个站点更加接近正态分布曲线。(3)AIRS的同化改善了RMAPS-CA对位势高度、温度、比湿等高空要素的预报效果,并未改善高空风速的预报。对各个要素,AIRS的同化改善幅度在低层较高层大。同化后,位势高度、温度、比湿和风速的预报RMSE分别小于20 gpm、2 K、8×10^-4 kg·kg^-1以及5 m·s^-1。Due to a scarcity of observation sites,only a small amount of conventional observation data on the temporal and spatial distribution of temperature and humidity in Central Asia can be obtained,which makes analysis difficult.High-resolution air infrared detector(AIRS)data can effectively fill the gap.In this paper,the radiance temperature of AIRS simulated by the input radiosonde in the Community Radiative Transfer Model was utilized as the reference value,deviations in the brightness temperature of the AIRS observation were analyzed,and the applicability of AIRS satellite data in the Central Asia numerical weather forecast operation system was evaluated.First,it shows that the average value of the maximum positive deviation of brightness temperature over the selected stations was approximately 3.3 K,and the absolute value of the maximum negative deviation was approximately 2.6 K.Second,the average brightness temperature of the AIRS observation in multiple stations was slightly higher than the overall simulated brightness temperature,and its probability density distribution was closer to the normal distribution curve than that of a single station.Finally,the assimilation of AIRS improved the prediction effect of RMAPS-CA on the geopotential height,temperature,specific humidity,and other high-altitude elements,but did not improve the prediction of high-altitude wind speed.For each factor,the assimilation improvement range of AIRS was larger at the lower and higher levels.After assimilation,the root mean square error of the geopotential height,temperature,specific humidity,and wind speed were less than 20 gpm,2 K,8×10^-4 kg·kg^-1 and 5 m·s^-1,respectively.It should be noted that,due to the time limitations imposed on the encrypted sounding experiment,only one full month in July 2016 was selected as the research time period in the deviation analysis of this study.Due to the relatively less vegetation coverage on the underlying surface in Central Asia,the surface radiation was large in summer,while the area without

关 键 词：AIRS 中亚 辐射亮温 偏差分析 适用性 

分 类 号：P412.27[天文地球—大气科学及气象学]