基于能量平衡的遥感蒸散模型研究进展

Advance in Surface Energy Balance Model for Estimation of Evapotranspiration Through Remote Sensing

近30年来遥感技术的迅猛发展,使陆地生态系统遥感蒸散模型在区域甚至更大尺度上的定量估算中处绝对优势。其中基于能量平衡的蒸散模型机理明确,应用最为广泛。根据基本原理与假设对比几种典型单、双层模型的优缺点及适用条件,指出在操作过程中模型面临的问题及误差来源,如时空尺度效应、"干""湿"限选取、地表温度反演等。对现阶段模型精度验证亟待解决的问题进行简要说明,认为应以在提高精度与简化步骤中寻找平衡点的辩证思想开发、选取模型。提出使用高分辨率、强指向性遥感数据、选取高效像元提取方法、开发适宜于遥感模型的气象数据插值方法等驱动模型发展、提高模型使用效果的设想。

Remote sensing technology has developed rapidly over the last 30 years. On the basis of this,a variety of algorithms have been proposed and applied to estimate land surface ET on field,regional and large scales,based mainly on energy balance theory which is welldefined. This paper reviewed and compared the advantages,disadvantages and application conditions of several typical single and dual-source models from basic principles and assumptions to indicate the problems and sources of errors,such as spatial and temporal scaling effects,selection of cold and hot anchor pixels,surface temperature,etc. And the paper also explained the difficulties of model accuracy verification.Newly-developed and selected models with dialectical thought between results and processes should be the future trends and prospects. Using high resolution and great expertise remote sensing data,selecting efficient pixel extraction methods,developing physically statistic or dynamic-feedback interpolation methods based on remote sensing data or making use of atmospheric reanalysis data at high spatial-resolution may be the promising subjects in the future for regional ET estimates.