山东省不同强度降水日数年际变化及趋势分布特征

Distribution of Climatic Trends and Inter-annual Variation Feature of Rainy Days in Different Grades in Shandong Province

采用山东省82个地面气象站1961～2005年日降水量资料,分析了降水量和不同强度降水日数的长期变化、突变特征及各地的气候趋势特征。结果表明,年降水量及中等强度以上雨日数的转折年大都出现在1976年前后,微量降水日数、0.1～4.9mm/d降水日数的转折年出现在1986年全球气候显著变暖背景下,其中暴雨、大暴雨日数在1989年也出现转折,增加趋势明显。在全球气候显著变暖背景下,中雨以上降水日数与1976～1986年相比都有不同程度的增加,强度越强的降水日数增加幅度越大,降水量的增加主要是由于强降水日数的增多引起的;年降水量、微量雨日数及小雨日数的线性负趋势区主要集中在山东高纬度地区,微量雨日数及小雨日数的负趋势区范围广,而中雨以上雨日数变化趋势大部分地区为正趋势,且趋势中心不固定。除鲁西南、鲁东南的气候变得更加湿润、暴雨洪涝灾害减少外,全省大部分地区干旱化趋势及洪涝灾害都有加重趋势。

Based on the daily rainfall data of 82 stations in Shandong Province during 1961-2005,the long-term variation and the sudden change characteristic of annual precipitation and rainy days in different grades,and climatic trends in different region of Shandong Province were analyzed by means of accumulative anomaly,skids the T-test,trend forecast and other statistical techniques.The result indicated that,in the variable of the rainy days test,a sudden change of moderate rainy days above spot in the mid 1970s,whereas the small and little rainy days have sudden change in 1986 under the global warming background.After the sudden change,fewer rainy days in all grades appear frequently,while the strong rainy days increase obviously.This causes the drought and the rainstorm flooding disaster is more frequent;under the nation-wide warming background the change tendency distribution of annual precipitation and rainy days in all grades has the obvious provincial characteristics：the negative tendency of the annual precipitation and total rainy days mainly displays in the high latitude area of Shandong,and the negative tendency of the small and little rainy days is more wide.Nevertheless the positive tendency of the strong rainy days is extensive.The phenomena showed that the climate becomes drought and rainstorm flooding disaster increases in mostly area of Shandong.