Climate Change Characteristics Analysis Of Lu’an District In Recent50Years

Lu’an is located in the center of Anhui Province,115°20’-117°14’E,31°01’-32°40’N, belongs to the transition band of the northern subtropical converse to temperate belt. The annual mean temperature is15.6℃, annual mean precipitation is1145.7mm, average annual sunshine hours is2017hours. In this paper, using the data of temperatures, precipitation and sunshine hours observed in the six observing station (Lu’an, Shou County, Shucheng, Jinzhai, Huoshan and Huoqiu) in Lu’an from1959to2008, analysis the annual, seasonal, monthly variation characteristics of temperatures, precipitation and sunshine hours, and the the simple correlation coefficient and partial correlation coefficient with a linear trend analysis; adds up the high-temperature days recent50years in Lu’an; check the abrupt change with sliding t-test, Cramer’s method, Mann-Kendall method; Finally, analysis the temperature and precipitation changes large and small period statistical by the wavelet analysis method, and to predict the variation law. The main results show that:(1) average temperature is increased generally and a larger increase after1996;spring, autumn and winter, the average temperature showed an increasing tendency, but declining slightly in summer. Temperature probably jumped in the period from1988to1998. In the50years, the temperature before the mid-1980s exited5-7years and quasi-15years periodic variation, after the mid-1980s exited quasi-7and quasi-3years variation.(2) average annual rainfall is1145.7mm, spring precipitation is25.22%of the total rainfall and summer44.50%, fall19.61%, winter10.67%.The correlation between precipitation and temperature or sunshine hours is negatively; temperature effect precipitation is mainly concentrated in the summer and autumn, and sunshine affection is more in the spring and fall. Annual variation trend of precipitation was not obvious, probably in the1980s has a catastrophe point. During the50years exited a quasi-20years periodic variation, and3-8years variation before the end of20th century, no obviously period in21th century.(3) annual average sunshine hours is2017hours, spring512hours,summer612hours, autumn482hours, winter408hours, average sunshine hours is168hours monthly. Annual sunshine hours has a downward trend, especially after1996began a larger decline. Summer, autumn and winter sunshine hours change showed a downward trend, while rise slightly in spring. Sunshine hours catastrophe appeared about in the late1980s to the early1990s...