中国近30年气候要素时空变化特征

Spatio-temporal patterns of climatic change in China in recent 30 years

利用1971-2000年中国603个气象站点逐日平均温度和降水量数据,借助ArcGIS空间分析工具,采用自组织特征映射模型（SOFM）,对中国气候变化的时空特征进行分析。研究结果表明：近30年中国气候变化的总体特征以增温为主,增温增湿的地区面积最为广大;季节变化构型也以增温增湿为主,秋季略有异常;从年代际变化来看,1971-1980年间,中国的气候以降温为主,而从1981年开始的20年间,全国的气候变化转为增温占主导。SOFM网络分类结果可以描述为缓增温少降水、剧增温平降水、缓增温缓降水和剧增温剧降水等四种类型。

Based on daily temperature and precipitation data of 603 meteorological stations from 1971 to 2000, the spatio-temporal patterns of climatic change in China were analyzed using ArcGIS and Self-organizing Feature Map （SOFM） neural network model. The results show that the overall trend of climatic change in China from 1971 to 2000 was warming, and characterized by warmer and wetter in most areas except for the Sichuan basin, a small part of the Yunnan-Guizhou Plateau and the northeast of the Tibetan Plateau. Similar to the annual trends, seasonal patterns of climatic change also exhibited warmer and wetter variation except for autumn. In autumn, the climatic change could be warmer and drier. Besides, it was hard to identify the areas that turned colder in autumn. No area was found to turn colder and drier in winter. The climatic change in China in recent 30 years showed there were significant interdecadal differences. The general trend of climatic change was dominated by temperature decrease from 1971 to 1980, while from 1981 to 2000, it reversed. The area that turned wetter during the period of 1981-1990 tended to be drier in the following 10 years. To compare with the results using Kriging Interpolation, we divided the meteorological stations into four types using SOFM. Based on the One-Way ANOVA test and statistical analysis of the properties, the clustering result of climatic change using SOFM was identified in four types, small warming rate with negative precipitation rate, dramatic warming rate with stable precipitation, small warming and precipitation rate, as well as dramatic warming and precipitation rate. There were two distribution areas of the first type. One included the North China Plain, the Loess Plateau and the Sichuan Basin, and the other concentrated in southern China. The second type consisted of Jilin and Liaoning provinces, the central part of Inner Mongolia, the Loess Plateau, the northeast of the Tibetan Plateau, some parts of Xinjiang and most parts of southern China. The third type was distributed in the northern part of Northeast China, the southeast of the Tibetan Plateau, most parts of the Yunnan-Guizhou Plateau and the north of Xinjiang. The fourth type was the most concentrated one and it had the least hes of thstations as well. It was located in the middle and lower reace Yangtze River plain and Central China.