石家庄夏季持续高温灾害的气候特征及形成机理

Climate Characteristic and Formation Mechanism of Continuing High Temperature of Summer in Shijiazhuang

利用石家庄17个站1955-2007年逐日气温资料分析了持续高温出现的天气气候特征,对2002年和2005年的3个时段持续(强)高温出现时的环流形势特征及夏季高温天气的形成机理进行了分析。结果表明:20世纪90年代以后,石家庄持续高温频次明显增多,强度增强;6月中旬-7月上旬为持续高温的多发时段;稳定的大陆暖高压、河套中尺度高压系统及其下沉增温作用,造成西部干旱区强暖气团发展、维持和缓慢东移,是导致持续高温的主要因素;太行山东麓的焚风效应也加大了持续高温强度。

Based on the daily surface air temperature data of 17 stations in Shijiazhuang during 1955 and 2007, the climate and synoptic characteristics of persistent high temperature was analyzed. Circulation features and formation mechanism of three persistently strong high temperature cases were analyzed in detail. The results showed that persistent high temperature continuity and strong high temperature events increased from 1990＇s, while the persistent strong high temperature mostly occurred from second ten days of June to first ten days of July. The Continental warm high pressure and meso-scale high pressure system in Hetao with downdrafts brought about strong warm air masses developed and maintained, and lead to persistent high temperature in Shijiazhuang. The foehn effect in the east foot of the Taihang Moutain strengthened the high temperature as well.