陕西省大气稳定度分布特征研究

根据陕西省97个气象台站2006—2011年逐时气象观测资料进行陕西省大气稳定度分类，统计计算各站四季及年不稳定类、稳定类和中性类稳定度出现的频率，利用GIS系统分别绘制关中区域分布图，分析了四季及年三大类稳定度出现频率的区域分布特征。结果表明稳定类和不稳定类均以秦岭腹地中西部和关中盆地中西部出现的频率为最高，其次是渭北及陕北黄土高原区，宝鸡西南部的凤县和太白，汉中市及安康西南部出现的频率较低；中性类明显以宝鸡西南部秦岭山区的凤县、太白，陕南汉中和安康西南部出现的频率为最高，关中盆地中西部和渭北东部最少；冬季稳定类出现频率最高，秋季次之，夏季最低；夏季不稳定类出现频率最高，春季次之，冬季最低；中性类以秋季为最高，夏季次之，冬、春季最少；不稳定类出现频率高的区域，稳定类出现频率亦高。

Distribution Characteristics of Atmospheric Stability in Shaanxi Province

Atmospheric stability was classified according to hourly observation of the 97 meteorological stations in Shaanxi Province from 2006 to 2011, frequency of occurrence of each station four seasons and years of instability, stability class, and neutral stability was calculated, regional maps of the Guanzhong area was drawed using GIS system, the distribution characteristics of the three categories of stability in seasonal and annual frequency was analyzed. Result show that the highest frequency of stable the class and unstable class are in the Qinling hinterland Midwest and Guanzhong Basin Midwest, followed by Weibei Loess Plateau,northern Shaanxi, Fengxian and Taibai county; Hanzhong City and Ankang southwest are lower frequency. The highest frequency of neutral class significantly are in Fengxian and Taibai county which situated in Baoji southwest Qinling Mountain,Hanzhong and Ankang southwest, The least frequency are in Guanzhong Basin Midwest and eastern Weibei. For stable class, winter appear most frequently, followed by autumn, and lowest in summer; For summer appear the highest frequency, followed by spring, lowest in winter; For the neutral class, the highest frequency appear in autumn, followed in summer, winter and spring is minimum. The high-frequency region of unstable class also are the region which have high-frequency of stable class.