Journal of Arid Meteorology

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Comparative Analysis of Two High Impact Cold-air  Snowfall over the Liaodong Peninsula

LIANG Jun 1, ZHANG Shengjun 2, HUANG Ting 1, ZHANG Lihong 1, HUANG Zhen 1

  1. 1. Dalian Meteorological Observatory of Liaoning Province, Dalian 116001,China;2.Chinese Academy of Meteorological Sciences/Lasw, Beijing 100081, China
  • Online:2015-06-30 Published:2015-06-30



  1. 1. 辽宁省大连市气象台,辽宁大连116001;2. 中国气象科学研究院灾害天气国家重点实验室,北京100081
  • 作者简介:梁军(1967-),女,正研级高工,主要从事短期天气预报和研究工作
  • 基金资助:



Based on NCEP final operational global analysis data, conventional observing data, satellite source, hourly precipitation from automatic weather stations (AWS) and radar data in Dalian, the diagnostic analysis were made about two cold-air snowfall processes in the Liaodong Peninsula on 27 November and 19 December 2013.The results show that both of high impact cold-air snowfall processes occurred during the revising period of transverse trough and snowfall appeared in the south of Dalian where the sea surfac temperature was relatively warm, both of 850 hPa temperatures dropped to -15 ℃ or lower, and both of air-sea temperature differences were more than 17 ℃. On the Doppler radar echo intensity field, the intensity of cumulus echo was about 15 to 25 dBZ, and the maximum echo height was less than 3 km. But when the Liaodong Peninsula was located in different areas of 500 hPa trough, it had different dynamic and thermodynamic environmental conditions. That is to say, when it was located in front of 500 hPa trough, its moist supply was plenty due to moisture transport from the Shandong Peninsula. Interaction between warm air and cold air was prone to formation of θse frontal zone with just beginning decrease of temperature in low-level, Dalian was located in the area of energy front and coastal front, and a positive vorticity advection in front of 500 hPa trough was just above the front zone, which caused strong upward motion in the lower and middle troposphere, and the low-level moisture was lifted to the high level, and the snowfall in that area enhanced. While when the Liaodong Peninsula was located in the southwest of 500 hPa trough, it transformed into cold core in low-level, and there was no formation of energy front and coastal front over that area, where the northerly wind produced downward motion and dynamic lifting was reduced. Correspondingly, the intensity of snowfall was relatively weak.

Key words: high impact, cold-air snowfall, comparative analysis, upper-level transverse trough, mesoscale coastal front


利用自动站、卫星、雷达和常规气象观测资料及NCEP 1°×1°再分析资料,对2013年11月27日和12月19日辽东半岛南部地区2次高影响冷流降雪过程的成因进行了对比分析。结果表明:2次冷流降雪均发生在横槽转竖的过程中;降雪落区均位于大连南部沿海暖水区域;降雪期间辽东半岛南部850 hPa气温均降至-15 ℃,海气温差均超过17 ℃,多普勒雷达上显示为15~25 dBZ的积云,回波高度不超过3 km。但辽东半岛相对于高空槽的位置不同,其降雪期间环境场的动力、热力条件有所差异。辽东半岛位于高空槽前,其与山东半岛的西南气流相连获得较多的水汽;降雪期间,低层处于降温初期,能量锋和海岸锋锋生,中层的正涡度平流输送,增强了上升运动和水汽抬升,降雪强度大。辽东半岛位于高空槽后,低层已为冷中心,无锋生过程,受下沉气流控制,大气层结稳定,动力抬升条件较弱,降雪强度弱。

关键词: 高影响, 冷流降雪, 对比分析, 高空横槽, 中尺度海岸锋

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