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为检验TESEBS(Topographical Enhanced Surface Energy Balance System)模型在高原地区的适用性,利用2014年高原9个站点的实测资料对TESEBS模型进行适用性检验,鉴于模型估算的感热通量偏差较大,提出利用地表温度_植被指数(LST-NDVI)特征空间法来确定蒸散发率,并将模型估算的卫星过境时刻瞬时蒸散发与实测值进行比较.结果表明:TESEBS模型估算高原不同下垫面的蒸散发与实测值之间的偏差较大;利用LST-NDVI特征空间法确定蒸散发率能很好地改善模型对蒸散发的估算精度,相关系数从0.65提高至0.83,均方根误差从144 减小至80 W?m-2,相对误差从67 %减小至39 %.特征空间法引入后,TESEBS模型估算的地表蒸散发明显小于原模型的估算结果,且模型给出的研究区地表蒸散发分布特征与植被指数NDVI的分布特征相一致.“,”The regional evapotranspiration can be estimated easily and quickly by using the Topographical Enhanced Surface Energy Balance System(TESEBS) model which has a great potential in the land surface process research.However,the accuracy of model was verified by using only two stations in the plateau.The applicability of the TESEBS model in different underlying surfaces remains to be verified.Based on the remote sensing data of Landsat7 and Landsat8,the simulation accuracy of TESEBS model was validated using the measured data of 9 sites over Tibetan plateau in the summer of 2014.Because the deviation of the sensible heat flux was larger,we used the LST-NDVI triangular method to estimate the rate of evapotranspiration in this paper.Compared to the observed value,the result showed that the deviation between the estimated evapotranspiration of the original TESEBS model and observed data was larger over the different underlying surface.But the accuracy of model was improved greatly by using the LST-NDVI triangular method in the model,the correlation coefficient was increased from 0.65 to 0.83,and the root mean square error was reduced from 144 to 80 W?m-2,and the mean absolute percent error was reduced from 67% to 39%.The evapotranspiration estimated by modified model was smaller than the result of original model,and the regional distribution characteristics of evapotranspiration estimated by the modified model were consisted with the NDVI index.