摘要
根据中国大陆 1 954～ 1 998年 338站沙尘天气频次 (日数 )资料、 1 948～ 1 999年 NCEP/NCAR 850 h Pa位势高度资料、 1 950～ 1 998年中国 1 60站月降水和气温资料分析了中国沙尘天气与降水、气温及扰动涡旋的相关关系。分析发现 ,沙尘天气的出现与气温和扰动涡旋的关系密切 ,表现为沙尘天气频次与冬春气温存在显著的负相关 ,而与春季 850 h Pa上的扰动涡旋有显著的正相关。基于上述关系建立了一个描述中国沙尘天气特征的指数 :沙尘指数。通过分析发现沙尘指数能较好地反映中国北方除新疆以外地区沙尘天气的变化规律。
In this paper, the daily 850 hPa geopotential high data of NCEP/NCAR reanalysis for 1948～1999 are used to find the vortex fluctuations, which represent daily cyclone activity in northern China. Three data sets, the grid cyclone frequency for 1948～1999, the 160 station temperature and precipitation for 1950～1998 are used to calculate the correlation with the 338 station dust day frequency for 1954～1998 in China's mainland. The result shows that the frequency of dust day is strongly corresponded with the low air temperature in winter and cyclone activity in spring. Based on this relationship, an index describing dust day frequency has been formulated. This dust index can well calibrate against the variability of dust day in northern China, except for Xinjiang region in Northwest China.
出处
《地理学报》
EI
CSCD
北大核心
2001年第4期477-485,共9页
Acta Geographica Sinica
基金
国家重点基础研究发展规划项目 ( G1 9990 4 34 0 5)&&
