2008年12月一次寒潮天气过程诊断分析

Diagnosis of a Cold Wave Weather Event in December 2008

利用国家气象中心实时预报业务数据库中的常规天气观测资料、美国国家环境预报中心和美国国家大气研究中心(NCEP/NCAR)1°×1°网格点逐6 h再分析资料,采用天气学原理和天气动力学诊断分析方法,对2008年12月3～6日寒潮天气过程进行分析和总结。结果表明,此次寒潮天气过程是500 hPa鄂霍茨克海附近强大的暖性高压脊阻挡冷空气东移,使冷空气堆积加强,形成横槽并转竖;泰梅尔半岛旋转南下的极涡南掉与转竖的低槽携带的冷空气合并,使冷空气势力增强并取西北路径从黄河流域大举南下,造成此次寒潮天气过程。强盛的冷平流是造成气温骤降的主要原因。

Using the national meteorological center real-time operational forecast weather observation data in the database, and （NCEP/ NCAR） 1°×1° 6h interval reanalyzed data of the United States conventional national center for environmental prediction and the national center for atmospheric research, by the way of the synoptic principle and dynamic diagnosis, the cold wave during 3 - 6 in December 2008 was analyzed. The results indicated that there was a powerful warm sex ridge at 500 hPa near the sea of Okhotsk, which held up cold air towards east, strengthen the cold air accumulation, formed horizontal slot and turned vertical; the polar vortex rotating southbound in Taymyr Peninsula southed off and merge the cold air of that low slot, intensified the cold air, which took northwest path from the Yellow River and swept south, brought about this cold weather process. The strong cold temperature advection is the main reason for air temperature dropping sharply.