AIRS红外高光谱卫星数据反演卷云光学厚度和云顶高度  

Retrieval of the Optical Thickness and Cloud Top Height of Cirrus Clouds Based on AIRS IR High Spectral Resolution Data

作　　者：曹亚楠[1,2] 魏合理[1,3] 戴聪明[1] 张学海[1,2] 

机构地区：[1]中国科学院安徽光学精密机械研究所中国科学院大气成分与光学重点实验室,安徽合肥230031 [2]中国科学院大学,北京100049 [3]中国科学技术大学环境光学学院,安徽合肥230031

出　　处：《光谱学与光谱分析》2015年第5期1208-1213,共6页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(61077081)资助

摘　　要：基于大气红外探测器L1B红外高光谱辐射观测资料,结合中分辨率成像光谱仪（moderate resolution imaging spectroradiometer,MODIS）云产品数据,利用通用大气辐射传输模式（combined atmospheric radiative transfer model,CART）,根据模式模拟和AIRS实际观测亮温的亮温差,研究从AIRS红外波段1 070～1 135cm^-1高光谱数据反演卷云的光学厚度和云顶高度。将反演的卷云光学厚度与云顶高度作为输入参数模拟计算650～1 150cm^-1波段卷云大气顶的辐射亮温谱,并将模拟值与AIRS观测亮温谱进行了对比分析。将反演的卷云光学厚度和云顶高度和AIRS的760通道（900.56cm^-1,11.1μm）的亮温以及MODIS卷云反射率进行了对比分析。最后将反演的卷云云顶高度和MODIS云顶高度进行了对比分析。研究结果表明：反演所使用的650～1 150cm^-1波段模式模拟和观测亮温谱吻合得很好,说明CART可以较好的模拟AIRS亮温谱。反演的卷云参数与AIRS在大气窗口区的760通道（900.56cm^-1,11.1μm）的亮温的分布满足低亮温对应较大的卷云光学厚度和高云顶高度。反演的卷云参数和MODIS卷云的反射率分布满足高卷云光学厚度和云顶高度对应高卷云反射率。反演的卷云云顶高度和MODIS的卷云云顶高度之间线性相关系数相对较高,且都在8.5～11.5km的概率较高,两者的概率分布趋势一致。说明CART可以用于反演卷云的性质,反演结果具有一定的可靠性。A study was carried out to retrieve optical thickness and cloud top height of cirrus clouds from the Atmospheric Infrared Sounder（AIRS）high spectral resolution data in 1 070～1 135cm^-1 IR band using a Combined Atmospheric Radiative Transfer model（CART）by brightness temperature difference between model simulation and AIRS observation.The research is based on AIRS L1 Bhigh spectral infrared observation data combined with Moderate Resolution Imaging Spectroradiometer（MODIS）cloud product data.Brightness temperature spectra based on the retrieved cirrus optical thickness and cloud top height were simulated and compared with brightness temperature spectra of AIRS observation in the 650～1 150cm^-1 band.The cirrus optical thickness and cloud top height retrieved were compared with brightness temperature of AIRS for channel 760（900.56cm^-1,11.1μm）and cirrus reflectance of MODIS cloud product.And cloud top height retrieved was compared with cloud top height from MODIS.Results show that the brightness temperature spectra simulated were basically consistent with AIRS observation under the condition of retrieval in the 650～1 150cm^-1 band.It means that CART can be used to simulate AIRS brightness temperature spectra.The retrieved cirrus parameters are consistent with brightness temperature of AIRS for channel 11.1μm with low brightness temperature corresponding to large cirrus optical thickness and high cloud top height.And the retrieved cirrus parameters are consistent with cirrus reflectance of MODIS cloud product with high cirrus reflectance corresponding to large cirrus optical thickness and high cloud top height.Correlation coefficient of brightness temperature between retrieved cloud top height and MODIS cloud top height was relatively high.They are mostly located in the range of 8.5～11.5km,and their probability distribution trend is approximately identical.CART model is feasible to retrieve cirrus properties,and the retrieval is reliable.

关 键 词：卷云 红外高光谱 AIRS 光学厚度 云高 反演 

分 类 号：O43[机械工程—光学工程] P351.3[理学—光学]