1964-2017年秦岭山地降水时空变化特征及其南北差异
刘 荷1, 邓晨晖3, 邵景安1,2, 郭 跃1,2

(1.重庆师范大学 地理与旅游学院, 重庆 401331; 2.重庆师范大学 三峡库区地表过程与环境遥感重庆市重点实验室, 重庆 401331; 3.咸阳师范学院 资源环境与历史文化学院, 陕西 咸阳 712000)

降水变化; 南北差异; 气温突变前后; 秦岭山地

Spatiotemporal Variations of Precipitation and the North-South Differences in the Qinling Mountains from 1964 to 2017
LIU He1, DENG Chenhui3, SHAO Jingan1,2, GUO Yue1,2

(1.College of Geography and Tourism, Chongqing Normal University, Chongqing 401331, China; 2.Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area, Chongqing Normal University, Chongqing 401331, China; 3.College of Resources, Environment, History and Culture, Xianyang Normal University, Xianyang, Shaanxi 712000, China)

precipitation changes; north-south differences; before and after the abrupt temperature changes; Qinling Mountains

备注

为了明确秦岭山地降水时空变化的特征,为秦岭生态环境保护提供气候依据,基于秦岭地区1964—2017年32个气象站的逐月降水数据资料并采用AUSPLIN插值法将其转为区域面上数据,结合小波分析、趋势分析等方法,研究了不同时空尺度下秦岭山地1964—2017年降水变化特征及其南北差异性。结果 表明:(1)近54年秦岭全区年均降水量呈减少趋势,速率为-11.95 mm/10 a,降水变化存在明显的周期性及显著的空间差异,降水主要集中在中南部。(2)季尺度上,近54年秦岭山地的降水变化存在显著的季节差异,空间上尤以春季在高海拔区的减少趋势最为显著。(3)秦岭山地降水变化存在着明显的南北差异,近54年北坡年均降水呈减少趋势,平均速率为-7.1 mm/10 a,南坡则呈增加趋势,速率为35.1 mm/10 a; 气温突变前,北坡降水变化趋势不明显而南坡以增加趋势为主; 气温突变后,南北坡均以增加为主,而北坡全区均呈增加趋势。54 a来,秦岭以南地区降水强度大,夏冬两季容易导致干旱、极端降水等自然灾害,进而对生命财产安全造成威胁,应增强旱涝灾害的预防。

In order to clarify the characteristics of the temporal and spatial changes of precipitation in the Qinling Mountains, provide a climate basis for the ecological environment, based on the monthly precipitation data of 32 meteorological stations in the Qinling area from 1964 to 2017, AUSPLIN interpolation method was used to convert those data to regional surface data. The characteristics of precipitation changes and the differences between North and South in the Qinling Mountainous area under different time and space scales from 1964 to 2017 were studied by using wavelet analysis and trend analysis methods. The results show that:(1)the average annual precipitation in the Qinling Mountains had decreased in the past 54 years, with a rate of -11.95 mm/decade; there is an obvious periodicity and significant spatial difference in precipitation changes. The precipitation is mainly concentrated in the central and southern regions.(2)on the seasonal scale, there had been a significant seasonal difference in precipitation changes in the Qinling Mountains in the past 54 years; the spatial reduction trend was particularly significant in spring at high altitudes.(3)the precipitation change in Qinling Mountain had obvious difference before and after the sudden temperature change; before the sudden temperature change, the decreasing trend was dominant, which reached the significance level in 82.21% of area; after the sudden change, the increasing trend was dominant, which accounted for 65.60% of the area;(4)there was a clear north-south difference in precipitation changes in the Qinling Mountains; in the past 54 years, the average annual precipitation on the northern slope had decreased, with an average rate of -7.1 mm/decade, and it had an increasing trend the southern slope, with a rate of 35.1 mm/decade; before the mutation, the change trend of precipitation on the north slope was not obvious and the increasing trend was mainly on the south slope. In the past 54 years, the south area of the Qinling Mountains had experienced high rainfall intensity. Natural disasters such as drought and extreme precipitation were likely to occur in the summer and winter, which threatened the safety of life and property. The prevention of droughts and floods should be strengthened.