The climate information system of China

Abstract

The Climate Information System of China (CISC) was built using Visual C++ and Java to perform 4 main functions: (1) to describe the variation in the spatial distribution of particular climatic variables with minimal digital information; (2) to separate the impacts of large-scale factors and local factors on climatic distribution and generate a raster database from the data collected from dispersed stations; (3) to share the climatic data on the Internet; and (4) to evaluate the impact of global change on Chinese water conditions under a number of prescribed climate scenarios. The establishment of CISC is described in detail. A digital elevation model and some meteorological (climatic) equations were used to calculate raster radiation data. Trend surface analysis and the interpolation method were used to analyze the spatial distribution of temperature, precipitation, relative humidity, sunshine fraction, and wind velocity and to generate the raster database. Penman's equation was amended and parameterized to calculate the potential evapotranspiration over China. An aridity index was calculated under present situations and 12 prescribed climate scenarios (raising mean temperature by 1.5, 3.0 and 4.5°C and changing precipitation by 0, +10, +20 and -10%) to assess the sensitivity of Chinese water conditions to global change. Some Java applets were written to make it possible to share Chinese climate information on the Internet.