索渺清,丁一汇,鲁亚斌,唐盛,樊炫君,李婧华. 2018. 中国南方准静止锋对冬季大范围冻雨的影响[J]. 气象学报, 76(4):525-538, doi:10.11676/qxxb2018.023
中国南方准静止锋对冬季大范围冻雨的影响
Effects of quasi-stationary fronts in southern China on large-scale freezing rain in winter
投稿时间:2017-09-15  修订日期:2018-05-03
DOI:10.11676/qxxb2018.023
中文关键词:  中国南方准静止锋  冷空气堆积  冻结层与融化层  锋区结构  冬季大范围冻雨
英文关键词:Southern China quasi-stationary front  Cold-air damming  Frozen and melt layers  Frontal structure  Large-scale freezing rain in winter
基金项目:国家自然科学基金重大研究计划项目(91637105)、高原与盆地暴雨旱涝灾害四川省重点实验室开放研究基金项目(SZKT201704)、国家自然科学基金面上项目(41475041)。
作者单位E-mail
索渺清 中国气象局气象干部培训学院, 北京, 100081  
丁一汇 国家气候中心, 北京, 100081 dingyh@cma.gov.cn 
鲁亚斌 云南省气象台, 昆明, 650034  
唐盛 云南省气象服务中心, 昆明, 650034  
樊炫君 华云信息技术工程有限公司, 北京, 100081  
李婧华 中国气象局气象干部培训学院, 北京, 100081  
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中文摘要:
      利用1979—2016年1月逐日0.125°×0.125° ERA-Interim再分析资料及冻雨观测资料,通过个例合成等方法,探讨了中国南方准静止锋和冬季大范围冻雨的关系。结果表明:(1)中国南方大范围冻雨受昆明和华南准静止锋共同影响呈东西带状分布;(2)青藏高原东侧逆温之强,范围之广以及水汽之充沛的主要原因,一是冷空气常堆积在横断山脉以东和南岭山脉以北等中国广大的南方地区,其形成机制主要为冷平流和绝热冷却,地势较高地带非绝热冷却也较明显;二是700和850 hPa暖平流形成的暖层也十分宽广;三是850 hPa源自中国南海和西太平洋的湿平流输送;(3)500 hPa东亚大槽、700 hPa南支槽、850 hPa反气旋和地面蒙古冷高压为青藏高原东侧对流层低层极地大陆性气团与热带海洋性气团和热带大陆性气团交绥创造了必要的环流条件;(4)东亚冷空气爆发从青藏高原东侧南下,迫使近地面暖湿气团抬升形成华南准静止锋。同时,受青藏高原东部地形的阻挡产生冷空气堆积。当冷空气堆积到一定厚度向西爬上低纬高原时,又与南支西风相遇形成昆明准静止锋。由昆明和华南准静止锋形成的复杂锋面结构,伴随宽广而强烈的逆温有利于中国南方大范围冻雨的产生。
英文摘要:
      Using daily ERA-Interim reanalysis data in global 0.125°×0.125° grids and freezing rain observations in January from 1979 to 2016, quasi-stationary fronts in southern China and their effects on the formation of large-scale freezing rain in the winter are analyzed based on composite analysis of several typical cases. The results are as follows:(1) Under the joint effects of the Kunming Quasi-stationary Front and South China Quasi-stationary Front, large-scale freezing rain over southern China often exhibits a zonal distribution pattern. (2) Three mechanisms are responsible for the intense temperature inversion, the vast area affected by the freezing rain and the abundance of water vapor in southern China. First, cold-air damming (CAD) along the eastern Tibetan Plateau usually leads to cold air mass accumulation to the east of Hengduan Mountains and north of Nanling Mountains, affecting vast areas of southern China. The CAD is mainly caused by cold advection and adiabatic cooling, although diabatic cooling can also be observed on high-altitude region. Second, the warm layer formed by warm advection at 700 hPa and 850 hPa can be widespread as well. Third, moisture advection from South China Sea and the Western Pacific at 850 hPa leads to abundant water vapor in southern China. (3) The joint effects of the East Asian trough at 500 hPa, the southern branch trough at 700 hPa, the anticyclone at 850 hPa and the Mongolian High near the surface provide necessary circulation conditions for the convergence of polar continental air mass, tropical oceanic air mass and tropical continental air mass in the low-level troposphere to the east of the Tibetan Plateau. (4) The cold air outbreak in East Asia moves southward along the eastern border of the Tibetan Plateau, forcing the near-surface warm moist air to rise and leading to the formation the South China Quasi-stationary Front. Once the cold air mass accumulates to a certain thickness, it would climb up along the estern slope of the Plateau in low latitudes and converge with the westerly winds of the southern branch, forming the Kunming Quasi-stationary Front. The complicated frontal structure in the Kunming Quasi-stationary front and South China Quasi-stationary front accompanied with the extensive and intense inversion is favorable for the formation of extensive freezing rain.
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