起伏地形下天文辐射分布式估算模型

基于数字高程模型（DEM），建立了起伏地形下天文辐射分布式估算模型.模型全面考虑了地形因子对天文辐射的影响，只需DEM数据作为输入项，适用于遥感图像处理、地理信息系统等数据处理平台.以1km×1km分辨率的DEM数据作为地形的综合反映，计算了我国全年各月天文辐射的空间分布.结果表明：我国年天文辐射总量有明显的纬向分布特点，随着纬度的降低，年天文辐射总量由北向南增加；由于受坡向、坡度和地形遮蔽因子影响，山区天文辐射表现出非地带性分布特征.本文所提供的我国天文辐射数据产品，可作为基础地理数据供相关研究应用.

Distributed modeling of extraterrestrial solar radiation over rugged terrains

Based on DEM (digital elevation model) data, a distributed model for calculating extraterrestrial solar radiation (ESR) over rugged terrains is developed. This model gives an all sided consideration on factors influencing ESR. Besides, the proposed model taking the DEM data as input has ability to process mass of data and is applicable to satellite image processing platforms or GIS (Geographic Information System). Using DEM data as the general characterization of terrains, ESR quantity with resolution of 1 km×1 km for the rugged terrains of China is calculated. The results suggest that the annual ESR quantity has clear latitude dependent variation characteristics and a progressive increase trend from north to south. The annual ESR quantity azonal distribution characteristics appear in mountainous areas owing to the effects of topographical factors such as aspect, slope and terrain inter shielding. The calculated ESR of China in this work can be employed as basic geographic data for relevant studies.