遥感技术和SEBAL模型在干旱区腾发量估算中的应用

陆地表面的腾发量分布具有很大的空间变异性,而传统方法只能进行点上的计算。为反映表面腾发量的空间特征,引入遥感技术和SEBAL(surface energy balance algorithm for land)模型。遥感技术能够方便、快捷地获取地面信息,而SEBAL模型则利用Landsat TM/ETM影像获取的遥感信息计算区域腾发量。该文在SEBAL模型的基础上,针对具体研究区域的客观情况进行参数改进,在ERDAS软件支持下,计算获得了研究区域地面反照率、地面温度以及各能量分量的空间分布。结果分析表明,参数改进后模型计算过程简捷,结果基本合理,具有广阔的应用前景,尤其对于缺乏观测资料的地区,更是一种行之有效的方法。

Remote sensing and the SEBAL model for estimating evapotranspiration in arid regions

Surface evapotranspiration has obvious spatial variability, but traditional measurement methods are based on point measurements. Remote sensing and the surface energy balance algorithm for land (SEBAL) model were developed to show the spatial variability of surface evapotranspiration. The remote sensing provides extensive surface information. The SEBAL model used the Landsat TM/ETM images as the main data source to calculate regional evapotranspiration with an improved model incorporating parameters for the specific study region. The calculated distribution of the spatial albedo, the temperature and the energy flux in the region were calculated in conjunction with the ERDAS software. The examples show that the results are reasonable. The model can be applied extensively, especially in areas where data is scarce.