Analysis on Characteristics of Climate Change in Last 49 Yearsin Southeastern Guizhou

The climate characteristics including temperature,precipitation,relative humidity and sunshine hours was analyzed by using conventional statistical methods and Mexican hat wavelet transform,based on the daily meteorological data of 16 meteorological stations in southeastern Guizhou from 1961 to 2009.The results showed that the annual average minimum temperature increased at the rate of 0.146℃ per 10 years,while the average temperature and average maximum temperature had no significant change trend.The annual average temperature decreased gradually from southeast to northwest,and its oscillation period was 3 years,17 years and 36 years.The annual average precipitation had no significant change trend but the days with rainstorm had a increasing trend.The annual precipitation decreased gradually from east to south and from west to north.Its oscillation period was 3 years and 18 years.The annual average relative humidity had no significant change trend but its oscillation period was 3 years,8 years and 11 years.The average sunshine hours decreased at the rate of 25.835 hours per 10 years,and its oscillation period was 4 years,10 years and 20 years.Totally,climate changed warmer and drier in last 49 years in southeastern Guizhou.