Mutations and cycle analysis of temperature in Yuzhong in recent 42 years

The characteristics of climate changes in Yuzhong was analyzed with the methods of the linear regression method, cumulative anomaly method, Mann-Kendall test method and Morlet wavelets analysis method based on daily average air temperature data observed at Yuzhong meteorological station from 1971 to 2012. The authors analyzed the climate changing characteristics and abrupt changes over the last 42 years in the area. The results showed that the climate in this region showed a warming trend, the annual mean temperature varied between 5.73 and 8.04 ℃, and the annual temperature has increased by 0.26 ℃·10 a-1 in recent 42 years, and an abrupt change occurred in 1995-1996.In addition, the seasonal temperature showed the same trend, and the increase of temperature in winter were higher (0.28 ℃·10 a-1) than in the spring (0.25 ℃·10 a-1). The climate change interval analysis that the annual mean temperature fluctuated significantly with the interval of 28 years,14 years and 6 years. There is an upward trend of temperatures in Yuzhong, with a certain period and the regularity of variation.