任珂,何金海,祁莉. 2010. 东亚副热带季风雨带建立特征及其降水性质分析[J]. 气象学报, 68(4):550-558, doi:10.11676/qxxb2010.053
东亚副热带季风雨带建立特征及其降水性质分析
The establishment characteristics of the East Asian subtropical monsoon rain belt and an analysis of its nature of precipitation
投稿时间:2008-02-13  修订日期:2008-05-26
DOI:10.11676/qxxb2010.053
中文关键词:  东亚副热带季风雨季, 南海夏季风, 低层水汽输送, 大气加热率
英文关键词:East Asian subtropical monsoon rain season  South China Sea summer monsoon  Moisture transport in the lower troposphere  Atmospheric heating rate
基金项目:国家重点基础研究发展规划项目(2006CB403607)、国家公益性行业(气象)科研专项项目(GYHY200706005)、国家重点基础研究发展规划项目“973”课题(2004CB418303)
作者单位
任珂 南京信息工程大学气象灾害省部共建教育部重点实验室, 南京, 210044 
何金海 南京信息工程大学气象灾害省部共建教育部重点实验室, 南京, 210044 
祁莉 南京信息工程大学气象灾害省部共建教育部重点实验室, 南京, 210044 
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中文摘要:
      利用1961—2006年NCEP/NCAR再分析数据集和TRMM、CMAP多年平均逐候降水资料,分析了中国东部副热带季风雨季的起始时间、建立特征及其降水性质。结果表明,第16—18候,在中国江南南部和华南北部地区(25°—30°N)日降水率达到6 mm/d,且范围较大,在低层该雨带的水汽主要来源于西太平洋副热带高压南侧转向的西南水汽输送,其源地即为西太平洋副热带季风雨季开始。雨带建立同时,东亚副热带地区—中东太平洋的纬向海平面气压梯度首先在中纬度发生反转,即西低东高(相应于西暖东冷)。中国东部副热带地区出现加热中心并伴有上升运动,强度逐渐增强,并伸展至对流层顶,其强度及对流高度与热带地区相当,对流层中低层大气呈对流不稳定,降水已具有对流性降水性质。与此同时,南海—西太平洋地区仍在副热带高压控制之下,盛行下沉运动,无降水产生,南海夏季风及其相应的水汽输送尚未建立。东亚副热带季风雨带的建立(3月底4月初)早于热带夏季风雨带,两雨带分别具有独立的热源中心和上升运动。南海夏季风即将爆发之际,赤道地区加热中心快速北移至南海地区,与副热带地区热源相互作用。
英文摘要:
      The initiation and distinctive establishment of the East Asian subtropical rainy season and its nature of precipitation are discussed based on the 1961-2006 NCEP/NCAR reanalysis data, the TRMM rain data and the CMAP rain data. The results show that at the end of March a wide range of strong precipitation begins to appear in the subtropical areas in eastern China with the daily precipitation more than 6 mm with the water vapor in the lower levels (from ground to 700 hPa) coming mainly from the southwest moisture transport turned in the south of the western Pacific subtropical high suggesting that the subtropical monsoon rain season is beginning. Meanwhile the seasonal reversal of the zonal pressure gradient (the land sea thermal contrast) between East Asia and the middle eastern Pacific takes place. The subtropical regions in East China begin to hold a heating centre accompanied by ascending motion. Several pentads later the intensity of the heating and the convective height which are gradually increasing are equivalent to those in the tropics. The convective instability atmosphere in the middle low levels is of. At the same time the South China Sea the western Pacific region is still under the control of the subtropical high with sinking motion prevailing without precipitation, and the South China Sea Summer Monsoon (SCSM) and its related water vapor passage have not been established yet. The establishment of the East Asian subtropical monsoon rain belt is earlier than that of the tropical monsoon rain belt. In addition, the two rain bands show the respective independent heating centers as well as the associated ascending motion. At the time of the onset of the SCSM, the heating center over the South China Sea rapidly moves northward to the subtropical area.
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