摘要
利用实况观测数据和NCEP/NCAR再分析资料,对2011年江苏出梅日的界定进行探讨,并将7月4—20日的低温高湿多雨、寡照的异常气候判定为"倒黄梅",在此基础上,对比分析了2011年和2009年的两次"倒黄梅"天气过程。结果表明:(1)2011年江苏出梅日为6月30日;(2)出梅后的7月4—20日是"倒黄梅"天气过程;(3)北上台风对梅雨和"倒黄梅"结束具有重要的指示意义;(4)"倒黄梅"和梅雨(含"二度梅")的天气特点为:前者冷暖空气频繁交替、雨带多经向分布、中低空温湿场反位相配置,常为低温高湿的局地对流性降水;而后者冷暖空气稳定对峙、雨带多纬向分布、中低空温湿场同位相配置,常为高温高湿的大范围稳定性降水。
By using the station-observed data and NCEP/NCAR daily reanalyzed data,the end date of Meiyu period in 2011 in Jiangsu is preliminarily studied.The abnormal climate process from July 4 to July 20 in 2011 is regarded as the ＇reoccurrence of Meiyu＇ period and has been analyzed in comparison with 2009,which are both caused by the southward movement of the rain band when the Meiyu period is considered to be over.Results show that：（1） June 30,2011 is considered as the end date of Meiyu period.（2）The period from July 4 to July 20 in 2011 is the ＇reoccurrence of-Meiyu＇ period which is due to the southward movement of the rain band.（3） The northward typhoon has an important significance for judging the end date of the Meiyu period or ＇reoccurrence of Meiyu＇ period.（4） There are some differences in atmospheric circulation between the ＇reoccurrence of Meiyu＇ period and Meiyu period.The former has a rain band by obvious meridional distribution and is usually local convective precipitation with low temperature and high humidity which is the anti-phase of temperature and humidity fields at the low and middle level because of frequent occurrence of cold air,while the latter has a rain band by obvious zonal distribution and is usually steady precipitation on a large scale with high temperature and high humidity which is the same phase of temperature and humidity fields at the low and middle level.
出处
《气象科学》
CSCD
北大核心
2012年第5期559-564,共6页
Journal of the Meteorological Sciences
基金
江苏省青年气象科研基金(Q201116)
关键词
出梅日
倒黄梅
温湿场
End date of Meiyu period
Reoccunrence of Meiyu
Temperature and humidity fields
