大连地区2008年“倒春寒”成因分析

Analysis on Causes for "Late Spring Coldness" in Dalian in 2008

利用NCEP资料,对2008年4月下旬、5月中旬大连地区2次"倒春寒"天气的成因进行分析。结果表明,500hPa贝加尔湖高压脊稳定维持或加强,脊前堆积的冷空气沿脊前西北气流向东南方输送,因此,贝加尔湖高压脊为冷空气南下提供通道,使得冷空气可以持续的下滑,导致4月下旬出现低温,形成"倒春寒";5月中旬东北冷涡活动频繁,大连地区多雨、低温天气比较显著,再次出现"倒春寒"。

The NCEP data was applied to analyze causes of two times ＂late spring coldness＂ in Dalian in late April and middle May of 2008. The results showed that 500hPa Baikal ridge of high pressure to maintain or enhance stability,ridge along the ridge before the accumulation of cold air flow northwest to southeast before transmission,therefore,Lake Baikal ridge of high pressure provide access for the cold air southward,so cold air can continue to decline,result in low-temperature in late April,form a ＂late spring coldness＂ ; cold vortex occurred frequency in northeast in middle May,rainy and low temperature weather was significant in Dalian,the phenomenon of ＂late spring coldness＂ appeared again.