秦岭山地气候变化的地形效应

研究不同地形下的山地气候变化对于植被生长、不同动物种群的生存习性及对气候的应激性有重要意义。本文基于陕西秦岭地区1959—2016年32个国家站的日气温和降水资料,采用Anusplin插值法、标准化降水蒸散指数(SPEI)、稳健回归和Theil-sen回归法等方法分析了山区地形对气候变化的影响。结论如下:(1)58年来秦岭四个坡向上年均温度随着海拔的升高呈现显著下降趋势,年降水随着海拔的升高呈现不同程度的上升趋势。温度随坡度的增加表现出下降趋势;除秦岭南坡西段外,降水随着坡度的增加呈现出上升趋势,但均不显著。(2)年尺度上,秦岭山地南坡和南坡东段的气温呈显著增温趋势,南坡西段和北坡呈不显著增温趋势;四个方向上的降水均呈显著下降趋势。秦岭山地四个方向上的干湿等级为正常,北坡和南坡西段的干湿状况一致,58年年均SPEI均为0.07,南坡东段较暖湿(0.08),南坡较暖干(0.05)。(3)季节尺度上,秦岭山地四个方向上除了夏季外,其他季节的气温均表现出不同程度的升温趋势,降水均呈下降趋势。秦岭四个方向上四季干湿变化属于正常等级。秦岭北坡出现春季干暖化趋势;南坡秋季较暖湿;南坡东段和西段的冬季呈暖湿化特征;南坡西段夏季呈现暖干化特征。

Topographic Characteristic of Climate Change in the Qinling Mountains,China

The study of the impacts of climate change in mountainous area in different terrains,is of great significance to vegetation growth,habits of different animal populations and environment.Using 32 meteorological stations'daily observed temperature and precipitation since 1959 to 2016,the influence of mountain topography on climate change were studied with the Anusplin interpolation method,Standardized Precipitation Evapotranspiration Index(SPEI),Robust Regression method and Theil-sen regression method.The results showed that over the past 58 years,the annual average temperature of the four slopes in the Qinling Mountains had shown a significant decreasing trend with the elevation,while the annual precipitation had shown an increasing trend in varying degrees with the elevation.The temperature indicated a decreasing trend with the increase of slope.Except for the western section of southern slope,the precipitation demonstrated an increasing trend with increasing of slope,but it was not significant.On an annual scale,the temperature on the southern slope and eastern section of southern slopes in the Qinling Mountains manifested a significant warming trend,while the temperature on the western section of southern slope and northern slopes revealed insignificant warming trend.Precipitation on four slopes revealed a significant decreasing trend.The dry and wet grade of four slopes in the Qinling Mountains was normal.The dry and wet conditions of the northern slope and the western section of southern slope were the same,which the annual SPEI for 58 years was 0.07,the eastern section of southern slope was warmer and wetter(SPEI=0.08),and the southern slope was warmer and drier(SPEI=0.05).On the seasonal scale,except for summer,the temperature on four slopes of the Qinling Mountains,all indicated varying degrees of warming trend,and the precipitation indicated a decreasing trend.The four slopes of the Qinling Mountains had normal dry and wet changes.The northern slope of the Qinling Mountains manifested a trend of dry warming in spring.The southern slope was warmer and wetter in autumn.In the winter on the eastern and western sections of southern slopes were characterized by warm and humid.The western section of southern slope showed a warm and dry feature in summer.