Climatic Change Tendency in Qinling Mountains from 1959 to 2009

The trends and characteristics of temperature and precipitation on north and south slopes of Qinling Mountains were analyzed based on temperature and rainfall data from 1959 to 2009 collected from 39 meteorological sites in Qinling Mountains.Results showed as follows:(1) Temperature presented an increasing trend over the last 50 years.The temperature tendency rate was 0.24 ℃/10 a for the north slope and 0.15 ℃/10 a for the south slope.After the middle of 1980s,the annually averaged temperature appeared an obvious climbing trend and the temperature tendency rate for the north slope,in particular,reached up to 0.74 ℃/10 a.After 1993,Qingling region witnessed an apparent climate warming trend.(2) Over the 50 years,the average temperature in the study area presented a very remarkable rising trend in spring,autumn,and winter,with a slight downward trend in summer(p0.01).Particularly,the rising trend of the average temperature was more notable in winter and spring.Temperature in summer showed an increasing trend in the 27 years from 1983 to 2009.(3) In the past 50 years,the annually averaged precipitation on the north slope increased,while it decreased on the south slope,which led to the reduction in the precipitation difference between the north slope and the south slope.However,in the last 15 years,both of the average precipitations on the north and south slopes increased slightly,with a faster pace on north slope of Qinling Mountains(230.4 mm/10 a).This indicated that the climate over the north slope of Qinling Mountains possessed a warming and wetting trend.