Analysis of Climatic Variations of Linfen Basin in Recent 40 Years

Based on the observation data of climatic factors in 17 meteorological observation stations in Linfen basin from 1977 to 2015, the climatic variations of Linfen basin were analyzed by means of linear tendency estimation and cumulative statistical analysis. The results show that the annual average atmospheric temperature and the annual average precipitation was 498.3mm in the past 40 years was 11.5 ̊C. The atmospheric temperature and precipitation of the Linfen basin both have showed an upward trend. The climatic change rate of annual temperature was 0.29 ̊C/10a, which passes the reliability test and accords with global warming climate background. The climatic change rate of annual precipitation was 5.40mm/10a, and the trend was not obvious, which accords with the average precipitation in China. The average atmospheric temperature in spring, summer, autumn and winter was 12.7 ̊C, 23.5 ̊C, 11.3 ̊C and −0.7 ̊C. The average temperature in spring, the annual average atmospheric temperature was 12.4 ̊C, which was closest to the average temperature in spring. The average precipitation in spring, summer, autumn and winter which accounted for 17.2%, 54.7%, 24.7% and 3.4% of the annual precipitation respectively. The summer precipitation contributed the most to the precipitation, followed by autumn, spring and winter. The inter-decadal variation of annual mean atmospheric temperature in Linfen basin showed a trend of “increasing-stabilizing”, and the inter-decadal variation of annual mean precipitation showed a trend of “decreasing-increasing”. The interdecadal variation of atmospheric temperature in the spring showed a trend of “stabilization-reduction” and a trend of “increasing-stabilizing” in summer, which also showed a consistent increase trend in autumn and winter. The interdecadal variation of precipitation in spring and summer presented a decrease trend, which showed a trend of “decreasing-increasing” in autumn and winter.