针对中国人多地碎的特点，将AVHRR图像和高空间分辨率图像配准，利用一种气象－遥感综合模型分别计算AVHRR像元整体及对应高分辨图图像中作物区的蒸散，给出两者之间的差异，分析并检验利用AVHRR图像计算大区域蒸散中由非单一地表产生的误差，并给出一种适用于所研究区域的相应的统计订正方法。

Mixed pixels constitutre AVHRR image. Evapotranspiration (ET) calculated based on AVHRR image certainly includes some errorous information of ground objects which have no meaning as far as ET is concerned. Registration of AVHRR image and high spatial resolution image is carried out. A meteorology-RS combination model is used to calculate the ET of the AVHRR image and that of the cropping area of the corresponding high resolution image respectively. The difference of these two ETs is given. The error is analysed and a corresponding statistical calibration method adaptable to the test region is given.