摘要
对蒙古国４０个气象站１９６１—１９９０年平均压、风、温资料作了分析，其结果表明：①冬季地形“中脊线”东西两侧的气候截然不同。西侧自由大气的暖平流很少触到地面，中小型地形的热力差异明显：气压场上为“多中心”，相应的盛行风场为多种多样；东侧为冷平流，可触及地面，中小型地形的热力差异不明显，气压场为相对少变，山脉影响一般形成不了闭合中心，西北风占绝对优势。不同地形坡向间温度差异较小。②夏季，高空控制气流（行星西风）减弱，“中脊线”以东的各地形性气压中心得以发展，向风面为高压（或脊）、背风面为低压，其中“色得格低压”和“克鲁伦河低压”为统流低压，而“呼伦贝尔低压”和“浑善达克低压”为背风下沉低压，干燥少雨成为沙漠区。夏季河套灌区近地层为一高压，其成因与人工灌溉关系极大。气温可用地理要素较好表达。
By analysing the mean pressure, dominent wind and temperature data of 40 observations in Mongolia from 1961 - 1990, some conclusions are as below: (1) The climate in the east and the west side to main ridge in winter are completely different. The warm advection in free atmosphere hardly reaches the ground in the west (weatern part of Mongolia and northern part of Xinjiang). The thermodynamic differences of various meso-and micro-tropography appear significent. there are 'multicenters' in air pressure field. and the dominant wind field is 'disorder', the temperature in convex concave orography and sun shade slope are different significent: there is cold advection in the east side. and it can reaches the ground. the thermodynamic differences of meso-and micro-orography are not significent. The air pressure field is as a 'unity'. The mountains can only produce high pressure ridge and low pressure trough. but closed centers. The wind field is dominated by the west, seldom are by south and the northeast. The temperature differences of venous slope directions is small. and it becomes smaller with height.(2) In summer. upper dominant flow (planetary west wind) become weaker, and the orographic air pressure centers in the east to the main fidge develop. The high preessure is in the windward side of mountain, and low pressure in the lee sides, and in which 'Selenge low' and 'Kelulun river low' in Kent mountain are flowing arround low, Hurn Buir low and Hunshandake low are lee sinking low. These areas become desert for dryness and lack of rainfall. In summer, there is a high pressure in boundary layer in Hetao irrigation region. it closely relate to artificial irrigation. Air temperature in summer can be expressed by latitude. longitude and elevation.
出处
《气象学报》
CSCD
北大核心
1996年第1期121-128,共8页
Acta Meteorologica Sinica
基金
国家攀登计划KJ185-03-03课题
关键词
蒙古高原
地面风
气压
温场
基本特征
Mongolian Plateau, Wind field, Field of pressure. Temperature field.Basic characteristic.
