云南高原临沧市城市相对湿度和干岛效应分析

Analysis of Urban Relative Humidity and Dry Island Effect in Lingcang City,Yunnan Plateau

利用临沧市市区和郊区1961-2010年气象观测资料进行对比分析,得出临沧市相对湿度和干岛强度的年代际、年际、月、日变化规律。结果表明：临沧市的相对湿度年变化呈下降趋势,季节变化夏季最大、春季最小,日变化08时最大、14时最小;临沧市从1971年开始干岛强度呈增强趋势,日变化08时左右较弱、20时达到最强,干岛强度月变化6月最弱、10月最强。利用灰色关联度分析影响临沧市干岛强度的人文因子和自然因子,结果得到对临沧市城市干岛强度影响最大的自然因子是低云量,对城市干岛强度影响最大的人文因子是城区人口,且人文因子大于自然因子的影响。

Based on the meteorological data of Lincang City and its suburbs during 1961~2010,this paper analyzed its regulations of interdecadal variation,annual variation,monthly variation and daily variation.The results showed that the annual variation of relative humidity has been declining,the most seasonal variation of relative humidity appears in summer,and the least appears in spring,and the most daily variation of relative humidity appears at 8o＇clock,and the least appears at 14o＇clock. Lingcang dry island intensity has begun to increase since 1971.At about 8o＇clock,the intensity of dry island effect is weak, and the most dry island effect appears at 20o＇clock.On the other hand,the least intensity of dry island effect appears in June, and the highest intensity of dry island effect appears in October.Through grey relationship analysis of the man-induced factors and natural factors which influence the intensity of dry island effect,we have drawn such a conclusion that the best part which influences the intensity of dry island effect in natural factors is the low cloud cover,and the best part which influences the intensity of dry island effect in man-induced factors is the urban population.Moreover,man-induced factors are more influential than natural factors.