微地形上太阳辐射模拟及与地表温度关系研究

Simulation of the total solar radiation over micro-landform and correlation between the solar radiation and the land surface temperature

在微地形上进行太阳辐射模拟对于探讨起伏地表微气候因素分布具有重要意义,为分析微地形对太阳辐射的影响及对地表温度的影响,利用实时动态差分仪(real-time kinematic,RTK)实地测量实验样区的微地形,生成分辨率为0.1 m×0.1 m的分米级高精度数字高程模型(digital elevation model,DEM),模拟微地形下太阳总辐射的时空分布;同时结合地面温度实测数据,建立地表温度与太阳辐射的关系。结果表明:微地形下太阳辐射具有明显的空间分布特征,表现为沟脊大,沟底小;阳坡大,阴坡小;坡度越大接受的太阳辐射量越少;实验样区接受太阳辐射量大小依次为夏季>春季>秋季>冬季;地形遮蔽效应对太阳辐射影响程度依次为冬季>秋季>春季>夏季;地表温度与太阳辐射呈显著相关,相关系数为0.622。

Solar radiation is the most important energy source in the Earth. The Yangxin＇s research shows that the effect of DEM scale causes great uncertainty to the simulation of solar radiation, and the impacts of DEM resolution on the simulation of the solar radiation are much greater in hilly area than in the mountainous area. To estimate the solar radiation model （ SRAD）, the authors measured the micro terrains with the help of real - time kinematic （RTK） and achieved the 0. 1 m × 0.1 m high - resolution DEM by TGO and ArcGIS10.0 software. Then the authors analyzed the correlation between the solar radiation and the land surface temperature. It is found that the solar radiation is differently distributed on the micro - landform. Groove ridge, sunny and gentle slopes accept more solar radiation than groove bottom, shady and steep slopes. The radiation is in descending order of summer（2 149.96 MJ/m2）, spring（ 1 903.97 MJ/m2）, autumn （1 461.86 MJ/m2） and winter （1 093. 11 MJ/m2）, and solar radiation is reduced gradually with the increase of the grade of slope. The results show that the land surface temperature is significantly correlated to solar radiation （0.622）.