摘要
利用NCEP每6 h 1次的1°×1°格点资料和中尺度模式WRF(V3.2),对2010年舟曲"0808"特大泥石流暴雨天气进行了数值模拟,运用模式输出资料对此次天气过程发生发展的机制进行了诊断分析。结果表明:舟曲强暴雨发生在高原短波槽、低涡切变线和副热带高压等共同作用的有利天气形势下,三重嵌套的WRF模式对此次暴雨具有良好的模拟能力。低层强辐合、中层无辐散和高层强辐散的配置,以及强烈的上升运动是此次暴雨发生的主要动力条件。从低层向上延伸的等θse线高能舌和水平风垂直切变为暴雨的发生输送了大量的不稳定能量。中低层水汽辐合上升为暴雨的发生创造了有利的水汽条件。
Based on the NCEP 1°×1° data with 6 h interval and the meso-scale WRF(V3.2) model,the physical mechanism of severe rainstorm caused by debris flow disaster on August 8,2010 was diagnosed.The results indicated that the severe rainstorm happened under the common action of short-wave trough at high altitudes,low vortex with shear line,the subtropical high and so on.The triple nested WRF model has simulated this rainstorm event quite well.The prime dynamic conditions of this process include strong convergence in the lower level,non-divergence in the middle level and strong divergence in the upper level as well as strong ascending motion.A lot of instability energy that rainstorm needs is transported by vertical wind shear and high energy tongue of pseudo equivalent potential temperature(θse) isoline which extends upward from the lower level.Convergence of water vapor in the middle and lower levels is favorable to rainstorm occurrence.
出处
《气象与环境学报》
2012年第2期54-59,共6页
Journal of Meteorology and Environment
基金
国家自然科学基金(41005074和40705020)资助
关键词
舟曲特大暴雨
WRF模式
数值模拟
诊断分析
Severe rainstorm in Zhouqu
WRF model
Numeric simulation
Diagnostic analysis