四川地区雾的气候特征及变化趋势研究

Research on Climatic Characteristics and Change of Fog in Sichuan

利用1961~2011年四川142个代表站的逐月雾日数资料,通过一元回归线性倾向趋势分析等方法,研究了四川雾日数的时空分布特征及变化趋势,得出以下结论:(1)四川雾日数分布有明显的区域地理特征,川西高原雾日明显比四川盆地少,高原大部地区整年无雾出现(平均雾日<1d),四川盆地平均雾日达到37d,其中峨眉山常年处于雾的笼罩之中(平均雾日达311.8d);(2)雾日数季节变化与下垫面地理特征也有密切关系,盆地雾日最多的季节是冬季,高原雾日最多的季节是秋季;(3)四川雾日数具有明显的年代际变化特征,经历了偏少-偏多-偏少的过程,总体呈现随时间增加的趋势;(4)四川年均雾日变化趋势的分布具有明显的地理特征,高原为负变化趋势,盆地为正变化趋势。

Based on the Observational data of fog from 142 base stations of Sichuan in 51 years,used simple linear regression,the basic climatic characteristics of fog in our province in temporal and spatial distribution are analyzed.The flowing phenomena were found:1.Distribution of fog showed obviously regional geographical features,which showed that fog days in plateau were fewer than in basin.There are barely fog days all the year round in most regions of plateau(average<1 d).Average fog days in basin and mountainous terrain were up to 37 d.Emei Mountain was fogged all the year round(average up to 311.8 d).2.Seasonal change of fog was also connected with surface geographic feature.The maximum of fog in basin and mountainous terrain was winter,differently in plateau which was autumn.3.Fog days in Sichuan has obvious interdecadal variation characteristics,which experienced less-more-less process,and increased over time.4.Change of fog in Sichuan also has close connection with surface geographic feature.Change in plateau was negative,but positive in basin and mountainous regions.