摘要
本文提出了一个表示降水与地形、海拔高度及地区气候条件关系的数学模式。通过计算和分析表明:地形对降水的最大影响是发生在盛行风向与向风坡坡向的交角σ接近于0°而向风面地形坡度α=45°左右时。σ愈小,地形对降水的增幅作用愈大。当α<45°时,α愈大,地形对降水的增幅作用愈大,背风面的降水比向风面减小愈少。当α>45°时,则正好相反。但是,当σ<45°和α在30°和60°之间时,地形对降水增幅作用随σ和α的变化并不很明显。在地形坡度均一的情况下,向风面降水的高度分布一般是先增后减,有一最大降水高度h_M出现,且气候愈干燥,h_M愈高。在气候很潮湿时,h_m→0,即最大降水高度出现在山麓。当向风面的地形呈阶梯形时,也可出现两个或两个以上最大降水高度。
In this paper, a model of simulating the effects of topography and elevation on precipi-tation is presented. The topography has the max num effects on precipitation when the angle a between wind direction and slope direction approaches aero and inclination a of slope is near 45. The smaller the angle a, the greater the in luence of slope on precipitation. In case of a<45, the larger the inclination, the greater the influence of slope on precipitation and the less the difference in precipitation between the w ndward slope and the leeward slope. When a> 45? the reverse holds. But the influences when a varying under 45?and a changing between 22皸68?upon precipitation are not so evident and can be neglected in general. In case of uni-form slope inclination, the precipitation on windward slope increases at first and then decreases in general, there appears a maximum precipitation height (hM) and the drier the climate, the greater the hM will be..If the mountain area is very moist, hM?, it means that the maximum pre-cipitation will fall on the foot of mountain, When the terrain on windward side is ladder like in shape, it is possible to have more than one maximun precipitation heights.
出处
《地理学报》
EI
CSSCI
CSCD
北大核心
1992年第4期302-314,共13页
Acta Geographica Sinica
基金
国家自然科学基金资助项目
关键词
地形
海拔
高度
降水
背风坡
Topography
Elevation
recipitation
Windward slope
Leeward slope
