基于Kriging空间插值气象数据、IGBP土地覆盖和AVHRR NDVI数据,利用Shuttleworth-Wallace模型估算韩江流域2000—2006年的潜在蒸散发(PET).结果表明:流域PET空间分布呈显著的非均匀性,其值在496.6~1741.8 mm/a范围内变化,标准差为165.9 mm/a,主要受区域的气候和植被类型影响;PET随气候的变化和植被的生长呈季节性变化;低分辨率的输入数据会使PET模拟结果在相同尺度的范围内被一定程度地均化;气象站点密度对PET的计算结果有影响,Kriging插值气象数据的站点密度远大于CRU数据,两种数据计算的PET结果的空间分布和季节变化的对比显示,前者计算的PET精度高于后者.%Based on meteorological data generated by Kriging spatial interpolation, International Geosphere-Biosphere Program ( IGBP) land cover data, and Normalized Difference Vegetation Index data observed by the Advanced Very High Resolution Radiometer ( AVHRR NDVI) , the potential evapotranspiration ( PET) in the Hanjiang River Basin during the period from 2000 to 2006 was estimated with the Shuttleworth-Wallace ( S-W) model. The results show that the spatial distribution of PET over the basin is significantly non-uniform, with annual PET values ranging from 496. 6 to 1741. 8 mm/a and an annual standard deviation of 165. 9 mm/a. The non-uniform distribution of PET is mainly caused by local climate and vegetation types. PET changes seasonally with climate and the growth of vegetation. Input data with low resolution may homogenize the PET results to a certain extent in the same coverage. The density of the meteorological stations will affect the estimated results of PET. The density of meteorological data from Kriging spatial interpolation is much higher than that of the Climatic Research Unit ( CRU ) data. The spatial distribution and seasonal change of PET calculated using the Kriging interpolation data and CRU data were compared, and the results show that the PET data calculated using the Kriging interpolation data are more accurate than those using the CRU data.
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