近地表气温遥感反演方法综述

A review of methods for estimating near-surface airtemperature from remote sensing data

关键词:  近地表气温  大气廓线  TVX  数据统计  地表能量平衡

Key words:  near-surface air temperature  atmospheric profile method  TVX method  statistical model  surface energy balance method

摘要:

【目的】在农业研究中，近地表气温是影响作物发育速度的关键因子。尤其是在全球 气温变暖趋势下，对区域尺度气温进行实时监测具有十分重要的科学意义和实用价值。文章 对目前常用近地表气温遥感反演方法进行回顾和总结，对未来近地表气温遥感反演方向进行 展望。【方法】随着遥感技术的不断发展，遥感近地表气温反演已成为目前获取高时间/ 空 间分辨率区域气温的最有效方法。该文采用文献综述的方法，回顾和总结了近年来国内外近 地表气温遥感反演研究进展，将其归纳为4 类：大气廓线外推方法、地表温度—植被指数方 法、基于数据统计的方法以及基于地表能量平衡的方法。最后对这些方法的优缺点进行评述 和展望。【结果】近地表气温主要受辐射、湍流及平流等多种因素影响。因此，准确获取近 地表气温十分困难。尽管目前已有多个行之有效的遥感反演方法，但这些方法大多依赖地面 辅助数据，尤其是在有云情况下，由于无法有效获取诸如地表温度和地表反照率等气温反演 的重要参量，目前的方法很难有效得到应用。【结论】国内外学者针对近地表气温遥感反演 开展了大量研究，但是目前仍然缺乏独立于地面辅助数据的普适性方法。建议未来在有云条 件和不同地形条件下大气辐射传输过程以及大气流动对气温影响的量化建模等方面加强研 究，以提升近地表气温遥感反演精度和适用性。

Abstract:

［Purpose］Air temperature is a key factor affecting the growth rate of crops in agricultural study. Under the trend of global warming，it is significant to monitor changes of air temperature in regional scale. The article discusses the current methods for estimating nearsurface air temperature from remote sensing data and looks forward to the future development of retrievals methods.［Method］With the development of remote sensing science，remote sensing technology has become an effective way for obtaining spatial distribution of air temperature with high temporal-spatial resolution. The article reviews and summarizes the recent research progresses for estimating near-surface temperature from remote sensing measurements. In general，these methods can be roughly catalogued into four types：atmospheric profile method，temperature-vegetation index method，statistical method，surface energy balance method. Finally，the advantages and disadvantages of these methods are evaluated. ［Result］Air temperature is generally influenced by radiation，turbulence and advection，thus making it difficult to obtain. Although a number of methods have been developed，most of them rely on auxiliary data whatever the complexity of the model. Moreover，in the case of clouds，many important parameters cannot be obtained such as land surface temperature，land surface albedo and so on.［Conclusion］Various parameterization algorithms have been developed to estimate near-surface air temperature from remote sensing observations. However，there is a long way to develop a universal parameterization algorithm without auxiliary data. It is necessary to explore atmospheric radiation transmission under conditions of clouds and different topography. To improve the research of near-surface air temperature method，influence of atmosphere on air temperature should be taken into consideration.