高原气象
高原氣象
고원기상
PLATEAU METEOROLOGY
2001年
1期
58-65
,共8页
干旱区%绿洲%中尺度运动%关键因子%敏感性实验
榦旱區%綠洲%中呎度運動%關鍵因子%敏感性實驗
간한구%록주%중척도운동%관건인자%민감성실험
利用一个非静力平衡的、高分辨的、二维中尺度大气数值模式, 并在仅考虑简单陆面过程的情况下, 模拟了干旱区中绿洲所诱发的中尺度运动, 并进行了这种中尺度大气运动的强度对绿洲水平尺度、绿洲与周围环境的水平热力差异、大尺度背景场水平风速和大尺度地表加热率等一些重要物理参数关系的敏感性实验研究。研究发现:中尺度大气运动强度随水平热力差异的增大而加强,随背景场水平风速和大尺度地表加热率增强而分别减弱。但随绿洲水平尺度的变化并不像前三个因子一样为单调函数,而是在绿洲水平尺度为20km时中尺度大气运动最强,绿洲水平尺度更大或更小时中尺度大气运动强度均会减弱。通过统计甘肃省河西地区的绿洲水平尺度分布规律,发现绿洲分布最集中的尺度在15~25km,与模拟所得到的能激发最强中尺度运动的绿洲水平尺度基本一致。
利用一箇非靜力平衡的、高分辨的、二維中呎度大氣數值模式, 併在僅攷慮簡單陸麵過程的情況下, 模擬瞭榦旱區中綠洲所誘髮的中呎度運動, 併進行瞭這種中呎度大氣運動的彊度對綠洲水平呎度、綠洲與週圍環境的水平熱力差異、大呎度揹景場水平風速和大呎度地錶加熱率等一些重要物理參數關繫的敏感性實驗研究。研究髮現:中呎度大氣運動彊度隨水平熱力差異的增大而加彊,隨揹景場水平風速和大呎度地錶加熱率增彊而分彆減弱。但隨綠洲水平呎度的變化併不像前三箇因子一樣為單調函數,而是在綠洲水平呎度為20km時中呎度大氣運動最彊,綠洲水平呎度更大或更小時中呎度大氣運動彊度均會減弱。通過統計甘肅省河西地區的綠洲水平呎度分佈規律,髮現綠洲分佈最集中的呎度在15~25km,與模擬所得到的能激髮最彊中呎度運動的綠洲水平呎度基本一緻。
이용일개비정력평형적、고분변적、이유중척도대기수치모식, 병재부고필간단륙면과정적정황하, 모의료간한구중록주소유발적중척도운동, 병진행료저충중척도대기운동적강도대록주수평척도、록주여주위배경적수평열력차이、대척도배경장수평풍속화대척도지표가열솔등일사중요물리삼수관계적민감성실험연구。연구발현:중척도대기운동강도수수평열력차이적증대이가강,수배경장수평풍속화대척도지표가열솔증강이분별감약。단수록주수평척도적변화병불상전삼개인자일양위단조함수,이시재록주수평척도위20km시중척도대기운동최강,록주수평척도경대혹경소시중척도대기운동강도균회감약。통과통계감숙성하서지구적록주수평척도분포규률,발현록주분포최집중적척도재15~25km,여모의소득도적능격발최강중척도운동적록주수평척도기본일치。
Using a non-hydrostatic, high-resolutional and two dimensionalmesoscale atmospheric numerical model, to take account of the condition of a simple land surface process, oasis-induced mesoscale atmospheric flow is simulated. The sensitivities of the mesoscale atmospheric flow to oasis horizontal spatial scale, thermodynamical difference between oasis and near desert, large-scale horizontal wind speed, large-scale surface sensible heat flux are studied. It is found that the oasis-induced mesoscale atmospheric flow becomes strong with an increase of thermodynamical difference between oasis and near desert, and it becomes weak with an increase of large-scale horizontal wind speed and large-scale surface sensible heat flux, but change of intensity of the mesoscale atmospheric flow with horizontal spatial scale of oasis isn't a monotonous function. The mesoscale atmospheric flow shall be the strongest when horizontal spatial scale of oasis is about 20 km, and it shall become weak when oasis horizontal spatial scale is smaller or larger. At the same time, the distribution of horizontal spatial scales of the oases in Hexi region is analysed, and it is found that the scale in which oases come in great numbers is 15~25 km. This scale is mainly identical with the scale in which oasis can induce the strongest mesoscale atmospheric flow.