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对冠层热红外出射辐射的精确物理描述，是利用遥感技术反演植被覆盖区域地表温度工作中的关键一环．侧重于零散射近似下表达连续植被冠层热辐射特征的间隙率模型，包括基本模型与附加光照修正项并考虑热点效应的光照模型，分别对应夜间和白天的冠层热辐射特征；并着重研究辐射的方向性分布，及其与叶面积指数、叶倾角等因子的关系；由于冠层内部温差，如叶片与土壤温差、光照叶片或土壤与处于阴影中的叶片或土壤之间的温差等，引起的冠层方向辐射特性．模型的理论计算值与地面实验实测数据吻合较好，证明模型能在一定范围内较好地反映植被冠层的热辐射特征．
The accurate physical description of the canopy thermal infrared radiation is a key part of the work of using the remote sensing technology to retrieve the surface temperature of the vegetation coverage area. Focus on the zero-scattering approximation of the thermal radiation characteristics of canopy continuous vegetative cover model, including the basic model and additional light correction term and consider the hot spot effect of the illumination model, respectively, corresponding to nighttime and daytime canopy thermal radiation characteristics; and focus on The radiation directivity distribution and its relationship with the leaf area index and leaf inclination angle; as a result of the temperature differences within the canopy, such as the temperature difference between leaves and soil, the temperature difference between light leaves or soil and the shadowed leaves or soil, Caused by the canopy radiation characteristics. The theoretical calculation of the model is in good agreement with the measured data of the ground experiment, which proves that the model can well reflect the thermal radiation characteristics of the vegetation canopy within a certain range.