近50年来秦岭南北气候分异研究

Study on Climatic Differentiation in the South and North Qinling Mountains in Recent 50 Years

全球变化就区域性而言,重点集中在脆弱生态区和自然地理区域的过渡地带,如海岸线、水分条件充足的堤度带及山地。秦岭南北的气候变迁是全球气候研究的重点。研究表明:近50年来,秦岭南北平均气温呈上升趋势,但在突变时间与幅度存在一定的差异。秦岭北部在1989年发生突变,升温幅度为0.03℃/a,夏冬两季升温幅度大;秦岭南部在1992年发生突变,升温幅度为0.01℃/a,同样夏冬两季升温幅度大。降水量秦岭南北呈减少趋势,北部与南部降水量减少幅度分别为1.36 mm/a和2.66 mm/a,北部夏秋季减少幅度大,南部春秋季减少幅度大。

As for regionality,the study emphases of global climate change are always in the ecological fragile regions and the transitional zones of physical geographic areas,such as the coastlines,mountains and the gradient zones with sufficient moisture.The Study on climate change in the south and north Qinling Mountains is of important significance in studying global climate change.In this study,the values of mean annual and seasonal temperature and precipitation were calculated based on the data observed by the meteorological stations in the south and north Qinling Mountains so as to analyze the climate change trend from the aspects of temperature and precipitation anomalies,5-year sliding tendency and long-term sliding tendency.In order to investigate the sharp climate change,the Mann-Kendall,sliding T and Yamamoto test method were plied.The results reveal that the average temperature in the south and north Qinling Mountains was in an increase trend,but there was a certain difference in the sharp change time and range： the sharp temperature increase（0.034 ℃/a） in the north Qinling Mountains occurred in 1989,especially in summer and winter,but that（0.014 ℃/a） in the south Qinling Mountains occurred in 1992,especially in summer and winter similarly.Precipitation in the south and north Qinling Mountains was decreased,it was decreased by 2.66 mm/a in the north Qinling Mountains and by 1.36 mm/a in the south Qinling Mountains,respectively,and its reduction was high in summer and autumn in the northern Qinling Mountains but in spring and autumn in the south Qinling Mountains.