地形对黄河流域太阳辐射影响的分析研究

起伏地形中太阳总辐射由直接辐射、散射辐射、周围地形反射辐射三部分组成，依据各部分太阳辐射产生机理的不同，分别设计模型以综合考虑天文因素、大气因素、宏观地理因素、局地地形因素（坡向、坡度、地形相互遮蔽）是必须的。基于数字高程模型（DEM）数据和遥感影像，在全面考虑各种因素的基础上，建立了依托常规气象站观测资料的起伏地形下太阳总辐射计算模型，完成了黄河流域1km×1km分辨率太阳总辐射分布式模拟。结果表明：受坡地自身遮蔽和周围山地相互遮蔽的影响，总体平均而言，山地接收的太阳总辐射较平地少；局地地形对太阳辐射的影响程度随季节而变，在太阳高度角较低的季节，局地地形的影响较为显著。

Distributed Modeling of Global Solar Radiation over Rugged Terrain of the Yellow River Basin

In rugged terrain, the global solar radiation (GSR) reaching on the surface is composed of three parts, i.e. direct solar radiation, diffuse solar radiation and terrain reflected solar radiation. The theories of these three kinds of solar radiation are different. Respective models are established which necessarily take integrated consideration of astronomical and geographic factors, local topographic factors (i.e. slope, aspect and terrain inter shielding effect) and atmospheric physics factors are needed. Based on DEM (Digital Elevation Model) data and remote sensing data, a distributed model for calculating GSR over rugged terrain is developed, with routine meteorological observations as input. This model takes all consideration of factors influencing GSR. Using the established model, normals of annual GSR quantity with resolution of 1 km×1 km for the Yellow river basin was generated. Results suggest that influenced by local topographic factors, i.e. azimuth, slope and terrain inter shielding effect, annual GSR quantity over mountainous areas is smaller than that over plains generally. The influences of local topographic factors on GSR are changing with seasons and are more obvious in seasons that have a lower solar elevation angle.