摘要
基于1 km×1 km分辨率的数字高程模型(DEM)数据,利用建立的起伏地形下天文辐射分布式计算模型,计算了黄河流域1 km×1 km分辨率各月天文辐射的空间分布.结果表明:局部地形对黄河流域年和四季天文辐射的空间分布影响明显;在太阳高度角较低的冬季,地理和地形因子对天文辐射的影响相当强烈,山区天文辐射的空间差异大,1月份向阳山坡(偏南坡)天文辐射可为背阴山坡(偏北坡)的2～3倍,极端天文辐射的差异可达10倍以上;而在太阳高度角较高的夏季,天文辐射空间差异较小,7月份不同地形极端天文辐射的差异仅在16%左右;四季中,地形对天文辐射影响的程度为冬季＞秋季＞春季＞夏季.
Based on a distributed model for calculating astronomical solar radiation (ASR), monthly ASR with a resolution of 1 km×1 km for the rugged topography of the Yellow River Basin is calculated, with DEM data as the general characterization of terrain. This model gives an all-sided consideration on factors that influence the ASR. Results suggest that (1) the annual ASR has a progressive decreasing trend from south to north; (2) the order of seasonal ASR is summer>spring>autumn>winter; (3) the geographical and topographical factors have robust effects on the spatial distribution of ASR, particularly in winter where a lower sun elevation angle exists; (4) the ASR magnitude for slopes with a sunny exposure is generally 2 or 3 times that of slopes with a shading exposure in January and the extreme difference of ASR for different terrains is over 10 times; (5) the spatial differences of ASR are relatively small in summer where a higher sun elevation angle exists and the extreme difference of ASR for different terrains is only 16% in July; and (6) the sequence of influence strength for topography is winter>autumn>spring>summer.
出处
《地理学报》
EI
CSCD
北大核心
2003年第6期810-816,共7页
Acta Geographica Sinica
基金
国家重点基础研究发展规划项目(G19990436-01) ~~
