运用热惯量估算大气下行长波辐射的遥感方法——以Landsat/TM为例  

Estimation of Downward Atmospheric Long-Wave Radiation Using Thermal Inertia based on Remote Sensing

作　　者：黄妙芬[1] 邢旭峰[2] 刘素红[3] 于凯[3] 程灿[3] 

机构地区：[1]中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室,北京100101 [2]大连水产学院海洋工程学院,大连116023 [3]北京师范大学地理学与遥感科学学院,北京100875

出　　处：《资源科学》2006年第3期37-43,共7页Resources Science

基　　金：中国科学院陆地水循环及地表过程重点实验室开放研究基金项目"基于热惯量用全遥感信息估算小流域蒸散量方法研究"(编号:WL2005002);大连水产学院院科研项目"利用MODIS数据源估算大气下行辐射方法研究"(编号:015692);北京市自然科学基金重点基金"北京城市绿地对水热CO2通量调节功能的遥感定量研究"(编号:4051003)

摘　　要：利用2004年北京小汤山精准农业示范基地星地同步试验中获取的自动气象站和红外辐射计观测资料,建立Landsat卫星过境时刻地表辐射温度T和空气温度T0的关系式,利用北京21个常规气象站观测资料,以及2004年5景TM图像,建立热惯量与大气水汽压的经验关系式,将获取的两个关系式代入得到广泛引用的Izionmon(2003)晴天大气下行辐射估算模型中,率先提出了根据像元的热惯量、地表辐射温度等遥感参数反演像元大气下行辐射的空间估算模型。通过利用实际测量值,对一个点的大气下行辐射估算值反演的地表净辐射通量和利用逐个像元估算的大气下行辐射估算值反演结果精度验证表明:利用逐个像元的大气下行辐射值估算地表净辐射通量,比利用单一大气下行辐射值来估算,精度提高了9.5%。这表明利用热惯量和地表辐射温度等遥感参数来估算非遥感参数大气下行辐射的思路是可行的,而且有应用前景。It becomes difficult to study the remote sensing quantificationally in the domain of geology and geography nowadays. As one of the important contents in studying the interaction between the land surface and the atmosphere, the determination and retrieval of the surface temperature and the surface net radiation fluxes will be directly impacted by the downward atmospheric radiation in terms of the precision of the retrieval. In this paper a new model describes the retrieval of the downward atmospheric radiation based on the thermal inertia of the pixel and the surface radiometric temperature which resolved the errors introduced by the unequally distribution of the atmosphere temperature and water vapor, and the replacement of the region with point. The correlation expression has been established between surface radiometric temperature （T） at the time of Landsat/TM passing by the study area and atmosphere temperature （ T0 ）, which has made full use of the observation datum acquired from the experiments of the agriculture demonstration field in Xiaotangshan, Beijing. The datum includes those recoeded by automatic weather stations and thermal infrared thermometers（80 samples）. The expression is, T0= 0.5087 ＊ T ＋ 9.5414（ R^2=0.78）. Through analyzing the datum from 21 regular weather stations in Beijing and 5 scenes TM TM images in 2004, beijing, the experience expression between the thermal inertia （P） and air vapor pressure （e0） was created（ 105 samples）, namely e0= 10.395 ＊ P ＋ 14.09（ R^2 = 0.78）. Furthermore, the model of Izionmon（2003） was used based on the two expressions, and the spatial model was given that retrieve the pixel downward atmospheric radiation （Rta） under clear day using the remote sensing factors, such as thermal inertia and surface net radiation fluxes, namely R1d=[1-0.35exp（-10^（10.395P＋14.09）/（0.5087T＋9.5414））]σ（.0.5087T＋9.5414）^4 The retrieval results were validated using experiment-measuring data in practice. The ret

关 键 词：Landsat/TM 热惯量 大气下行长波辐射 地表净辐射通量 

分 类 号：P422[天文地球—大气科学及气象学]