东亚地区硝酸盐湿沉降的数值模拟

Numerical Simulation of Seasonal Variation in Nitrate Wet Deposition over East Asia

利用多尺度空气质量模式系统(RAMS-CMAQ),模拟了2005年东亚地区降水和硝酸盐湿沉降的时空分布。模拟结果显示:1月份湿沉降主要分布在我国长江以南地区和日本海,最大值出现在云南、广西、贵州及日本松江附近海面,可达600mg/m2以上;4月份沉降量最小,主要分布在我国东北、华东、西南和华南地区以及泰国等,最大值在350mg/m2以上;7月份分布最广,最大值达650mg/m2以上;10月份酸沉降主要分布在我国西南等地区和东南亚地区,最大值达600mg/m2。

The Models-3 community multi-scale air quality modeling sys- tem （CMAQ） coupled with the regional atmospheric modeling system （RAMS） was used to simulate the nitrate wet deposition from January 1st to December 31, 2005 to over East Asia to investigate its seasonal variation. The precipitation and wet deposition in January, April, July and October were presented. The results showed noticeable differences among the four seasons. Generally the nitrate deposition was higher in summer and lower in other seasons, which reflected the seasonal variation of precipitation. In winter, it mainly distributed in south of the Yangtze River and Japan Sea and the maximum was 600 mg/m^2, appearing in Yurman, Guangxi, Guizhou and south of Japan Sea. While in Spring, the maximum reduced to 350 mg/m^2, which occured in Northeast China, South China and Thailand, respectively. The magnitude of wet-deposition of nitrate reached its maximum （650 mg/m^2） and its distribution was the most extensive in summer, with subsequent decrease in autumn.