摘要
利用2006年7月14—15日的NECP/NCAR全球1°×1°再分析、站点降水和探空资料,研究了对流层中上层干空气对"碧利斯"台风造成的湖南暴雨的影响。结果表明,暴雨发生前对流层中上层500～200hPa有大片相对湿度低的干区,暴雨发生后干区减弱消失。干区与不稳定能量之间有一定的对应关系。受东风气流影响,干区向偏西方向移动;较强的水汽垂直输送也有利于暴雨发生前雨区上空干空气的减弱。敏感性试验证明对流层中上层干空气对不稳定能量有一定的积累作用;在增强干空气相对湿度的情况下,干空气的减弱对降水量的减少有一定影响。
By using the NCEP/NCAR reanalysis data（ 1°×1° ）, station precipitation and sounding data on 14--15 July 2006,a study on the effects of dry air in the upper troposphere on Bilis rainstorm in Hunan Province was conducted. The results show that there was a large area of dry air between 500 hPa and 200 hPa before the heavy rain occurred. The dry air weakened and disappeared after the heavy rain occurred. There are some correlations between the dry air and the instable energy. The dry air shifted westward with easterly air flow;it also weakened with the vertical vapor transport above the rain area. Sensitive experiments show that the dry air has some effect on the accumulation of instable energy, and its reduction has some influence on precipitation in the condition that its humidity increases.
出处
《大气科学学报》
CSCD
北大核心
2010年第1期98-109,共12页
Transactions of Atmospheric Sciences
基金
国家重点基础研究发展计划项目(2004CB418304)
江苏省六大人才高峰项目(07-A-012)
关键词
碧利斯
暴雨
干空气
数值模拟
Bilis
rainstorm
dry air
numerical simulation
