1961~2011 年中国降水时空变化特征分析

Analysis of the Characteristics of China Precipitation Changes during 1961-2011

摘要:

利用中国气象局国家气象信息中心 1961~2011 年的中国地面逐月降水量网格数据集，通过数据统计以及 EOF 分解对中国区域 51 年间的降水时空分布特征进行了分析，结果显示：1961~2011 年间，降水量总体上经过了先减少后增加再减少的过程，经历了两次较为明显的低谷，分别为 1963~1973 年以及 2003 年以来；我国降水量从东南向西北递减，在东南沿海地区分布较多，新疆、青海以及甘肃西北部地区降水分布较少，7 月和 10月降水量的高值区出现东南沿海偏内陆地区，出现多个降水大值中心；且在 EOF 分解中第一个主模态全国区域表现为相似的变化特征，我国东南沿海地区的变化特征为主要的变化特征区域；我国东南沿海的降水量变化可主导中国整个区域的降水量变化特征。

Abstract: Statistical and EOF analysis was conducted to investigate the 51 years (from 1961 to 2011) of temporal and spatial distribution of precipitation over China by using monthly gridded precipitation data from the National Meteoro- logical Information Center of China. Generally speaking, from 1961 to 2011, precipitation decreases from 1963 to 1973 then increases until 2003, after then precipitation decreases again. Precipitation amount decreases from the southeast of China to the northwest. Precipitation is more over the southeast coastal area of China, while it is less over Xinjiang, Qinhai and Gansu province. The high value zone of precipitation amount in July and October appears over the southeast coast inland. The first mode of EOF decomposition shows similar variation characteristics over the whole country. Southeast China is the primary variation characteristic area. The precipitation amount variation of Southeast China can dominate the precipitation variation characteristic of the entire country.