The climate regionalization in China for 1981-2010

Abstract

The scheme of climate regionalization in China was conducted by the classification criteria of temperature zone, arid/humid region and climatic sub-region, and the variables used in the criteria were calculated as mean values of the 30 years by using the daily meteorological data of 658 stations from 1981 to 2010. In the classification criteria, the temperature zones were classified by the general guideline of the days with daily temperature steady above 10℃, and the secondary guideline of January mean temperature, or by their referenced variables including the accumulated temperature with daily temperature steady above 10℃ and annual minimum temperature, respectively. The arid/humid regions were classified by the annual aridity index and annual precipitation amount in turn. The climatic sub-regions were classified by the July mean temperature. The result shows that China can be divided into 12 temperature zones, 24 arid/humid regions and 56 climatic sub-regions. Compared with the climate regionalization scheme for the period of 1951- 1980, several boundaries of temperature zones in eastern China shifted northward in 1981-2010 due to the climate warming. The east part of the northern boundary of warm temperate zone shifted more than 1.0° at a maximum. On average, the east part of the northern boundary of north subtropical zone shifted 1.0°. The middle part of the northern boundary of mid-subtropical zone shifted 2.0° at a maximum. The west part of the northern boundary of south subtropical zone shifted 0.5°-2.0°. In West China, the shift of temperature zone was not significant in horizontal due to the vertical landform. However, the plateau sub-cold zone was shrunk while the plateau temperate zone was enlarged in the Tibetan Plateau. Because precipitation decreased in North China, southeastern part of Northeast China and eastern part of Northwest China, the boundary of the semi-arid and sub-humid region in Northern China shifted eastward and southward, and in which, the boundary between 36°-41°N shifted 0.5°-2.5°at longitude. Moreover, the climate in the most of arid regions and semi-arid regions in Hexi Corridor, Xinjiang and the Tibetan Plateau changed to be more humid.