基于MODIS数据的金塔绿洲上空大气水汽含量反演研究

2004年夏季,选择天气状况较好的时段在金塔县施放探空气球,采集高空温、压、湿等气象要素计算整层大气水汽含量。同时选取EOS-MODIS遥感资料近红外波段,反演整层大气水汽含量。反演结果与实测结果对比表明:最大相对误差为8.02%、最小相对误差为0.70%,平均相对误差为4.5%,反演结果可信。从绿洲上空水汽含量区域分布及沿着探空站南北向和东西向剖面看,水汽含量在空间分布上存在较大差异。戈壁沙漠上空水汽含量相对较少,绿洲上空水汽含量相对较大;绿洲边缘或通过沙漠的窄长护林带、河流以及水渠附近,存在着影响绿洲稳定和发展的“晒衣绳效应”。

MODIS-based reversion of atmospheric water vapor content over Jinta Oasis

During the Jinta experiment in 2004,sounding balloons were set free to collect the meteorological data in the upper air,such as temperature,pressure,and humidity to calculate the total water content in the air.Then,the remote sensing data of EOS-MODIS are used to revert the total water vapor content.The retrievals are compared with the observed ones,as a result,the maximal relative error is 8.02%,the minimal is 0.70% and the average relative error is 4.5%,which shows that the reversions are believable.According to the regional distribution of the water vapor content and the section plane along the sounding site from East-West and South-North,there is biggish difference in the spatial distribution of the water vapor content.The water vapor content,in all,is relatively less over the gobi and hungriness and more over the oasis;there is "the clothesline effect"which influences the stabilization and development of the oasis at the margin of the oasis or the long and narrow protection forest through the deserts or in the neighborhood of the river and the aqueduct.