陆面蒸散的双源遥感模型及其在华北平原的应用

Dual-source remote sensing model for estimating land surface evapotranspiration and its application in North China Plain

建立了一个计算陆面蒸散的双源遥感模型,利用多光谱和热红外遥感数据估算地表土壤缺水状况,并计算蒸散通量。本模型利用2000-2002年的13期Landsat TM和ETM+遥感数据计算了栾城地区1 000 km2范围的蒸散通量。通过与地面同步微气象观测值的对比,显示利用笔者建立的双源蒸散模型和简化的植被指数-地表温度梯形法确定土壤水分状况,在华北平原能够获得比较满意的计算结果。

Based on the theory of linear dual-source model for estimating the land surface ET. The remote evapotranspiration （ET） model, this paper develops sensing model has two characteristics： to （1） simplify a remote sensing the VITT method and improve the accuracy of determining soil water status in a semiarid irrigation area, and （2） introduc the dual-source model in calculating land surface ET and improve the calculation accuracy of the mixed pixels. The remote sensing model is applied for calculating the land surface ET about a 1000 km^2 in North China Plain by using 13 Landsat TM and ETM ＋ images during the period 2000 - 2002. It is illustrated that the remote sensing model based on dual-source linear concept can get good estimates when applied in semiarid irrigated area.