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SEBS模型为研究高原非均匀地表区域蒸散量估算提供了一种新的方法,为高原气象台站稀少地区蒸散量变化研究提供一定的参考依据。应用SEBS模型,利用MODIS遥感数据反演所需的地表物理参数(如反照率、比辐射率、地表温度和植被覆盖度等),再结合气象站地面观测数据,包括温度、相对湿度、风速、气压等,对藏北那曲地表能量通量和蒸散量进行估算;最后分析了蒸散量与气象因子、NDVI之间的关系。结果表明:2010年藏北那曲蒸散量呈春夏季高,秋冬季低的变化趋势,蒸散量较大区域为研究区南部、东北部和区域内的水体;中部和西北部地区蒸散量较小。气温和地表温度对蒸散量的影响较明显,随着气温和地表温度的升高蒸散量不断增大,NDVI对蒸散量也有一定的影响。所以,SEBS模型在估算高原地区蒸散量方面具有一定的精度,可以满足区域日蒸散发估算的需要。
The SEBS model provides a new method for the study of regional evapotranspiration estimation on non-uniform plateau and provides some reference for the study on evapotranspiration in the rare area of meteorological station. The SEBS model is used to retrieve the surface physical parameters (such as albedo, emissivity, surface temperature and vegetation coverage) needed by MODIS remote sensing data. Combined with the observational data of weather stations, including temperature, relative humidity, wind speed, Atmospheric pressure and so on, to estimate the surface energy flux and evapotranspiration in Nagqu, northern Tibet; finally, the relationship between evapotranspiration and meteorological factors and NDVI is analyzed. The results show that the evapotranspiration of Nagqu in Tibet in the spring is high in spring and summer, low in autumn and winter. The areas with large evapotranspiration are the water bodies in the south, northeast and area of the study area. The evapotranspiration is small in the central and northwestern areas. The effect of temperature and surface temperature on evapotranspiration is obvious. With the increase of temperature and surface temperature, the evapotranspiration is increasing, and the NDVI also has certain influence on evapotranspiration. Therefore, the SEBS model has certain accuracy in estimating the evapotranspiration in the plateau, which can meet the needs of regional evapotranspiration estimation.