我国东部极端降水时空分布及其概率特征  

Extreme Precipitation Experimentation over Eastern China Based on L-moment Estimation

作　　者：蔡敏[1] 丁裕国[1] 江志红[1] 

机构地区：[1]南京信息工程大学江苏省气象灾害重点实验室,江苏南京210044

出　　处：《高原气象》2007年第2期309-318,共10页Plateau Meteorology

基　　金：江苏省气象灾害重点实验室基金项目(KLME050209);国家自然科学基金项目(40675043)联合资助

摘　　要：利用我国105°E以东地区210个测站近50年（1953-2002年）逐日降水资料，在REOF客观分区的基础上，确定各分区的极端降水最佳采样期为1～2日。进而研究了日极端降水量的气候特征。采用具有优良特性的L-矩参数估计方法对我国东部极端降水拟合Gumbel分布。结果表明，L-矩参数估计方法的拟合优度比其它方法有进一步提高，近50年来，极端降水趋势虽无明显变化，但其时空差异较大。符合Gumbel分布的极端降水重现期的地理空间分布，大致特征是，东南大、西北小，两湖盆地、黄海海湾及辽东半岛也有高值区。Based on the 210 stations data of daily precipitation over Eastern regions are divided by REOF. The best sampling time length of extreme event China defined in 1953-2002, 12 is 1～2 days, and then analysis the climatic characteristic of extreme precipitation during the time length. The asymptotic distribution is fitted using the Gumbel Distributions, L-moment is an effective method to parameter estimation, with which the fitting precision are improved. The results show that, in past 50 years the trend of extreme precipitation over Eastern China changes little, but large difference is exsit between different decads and regions. The spatial distribution of current extreme precipitation and extreme value with a return period indicate in two-lakes ba that extreme precipitation decreases from southeast to northwest, there is also a high value sin, Huanghai bay and Liaotung peninsula.

关 键 词：我国东部 极端降水 L-矩估计 Gumbel分布 重现期 区域极值 

分 类 号：P426.6[天文地球—大气科学及气象学]