诱发渤海风暴潮的黄河气旋动力学诊断和机制分析  

Dynamic Diagnosis and Mechanism Analysis of Yellow River Cyclone Induced Bohai Storm Tide

作　　者：黄彬[1] 陈涛[1] 康志明[1] 向纯怡[1] 

机构地区：[1]中国气象局国家气象中心,北京100081

出　　处：《高原气象》2011年第4期901-912,共12页Plateau Meteorology

基　　金：黄渤海高影响天气预报中的关键技术研究项目(GYHY201106006);国家重点基础研究发展计划项目(973计划)(2009CB421504)共同资助

摘　　要：利用数字化6.7μm卫星水汽图像、NCEP/NCAR 1°×1°再分析资料,以及干侵入和位涡理论,对2007年3月3～5日诱发渤海罕见风暴潮过程的黄河气旋进行了天气动力学诊断和机制分析。结果表明,这次风暴潮是在欧亚中高纬度环流调整、高纬不稳定低槽东移发展及东亚大槽重建的过程中发生的,强烈发展的黄河气旋产生强偏北大风,导致渤海潮位暴涨。对流层顶附近的干冷空气伴随着大位涡舌区、水汽图像上暗区向对流层中低层侵入;当干侵入与输送带的暖湿空气汇合成强水平变形区,形成斧形干区时,气旋移到上下连通的大位涡区中爆发性发展;干湿汇合的核区形成的螺旋型结构是气旋发展的成熟阶段。在气旋中心区低θw值的干侵入空气叠加在高θw值的暖湿空气上,出现了位势不稳定层结;干侵入空气下沉,静力稳定度变小,绝对涡度增大是引发气旋爆发性发展的热力和动力的强迫机制。变压梯度、气压梯度、高空风动量下传和超低空急流的偏差风辐散共同作用,形成渤海风暴潮的强风。Using the digital 6.7 μm satellite water vapor image and NCEP/NCAR 1°×1° reanalysis data,the synoptic and dynamic processes of Yellow River cyclone induced Bohai storm tide is diagnosed based on the dry intrusion and potential vorticity theories.The result shows that the storm tide occurred during the adjustment of Eurasia mid-and high-latitude circulations,east moving and development of unstable low tough and the rebuilding of East Asian trough.Northerly gale wind induced by strongly developed Yellow River cyclone forced the sharp increase of tide over Bohai tide sharply bloomed.Dry cold air from tropopause with high potential vorticity intruded into lower level troposphere shown as dark area in vapor image,when the dry cold air encountered with warm moist and wet air from low troposphere,it was distorted into an axe-shaped dry air area which manifested a strong horizontal deformation.Then the cyclone rapidly strengthened when it moved to the area with bigger potential vorticity from upper to lower levels.It followed by the mature of cyclone when the spiral structure can be found in the dry and wet area.In the center of cyclone where the dry air with lower θw superposed the warm air with higher θw,which increased the potential instability.The mechanism of rapid intensification of cyclone can be shown as follows： Firstly,the downward intrusion of dry air into low level;secondly the reduction of static stability of atmosphere and augmentation of absolute vorticity;finally,the quick development of cyclone.The isallobairc gradient,pressure gradient,downward propagation of upper level momentum and divergence of super-low-level jet all contributed to the gale wind during the Bohai storm tide.

关 键 词：黄河气旋 风暴潮 干侵入 位涡 

分 类 号：P434.3[天文地球—大气科学及气象学]