| 摘要: |
| 本文利用多种观测资料、再分析资料及WRF（Weather Research and Forecasting Model）模式，对2017年12月23—25日发生于中国东部沿海入海加强的一个强暴发性气旋进行了研究，并探讨了海陆地形和热力差异对暴发性气旋发展的影响。该暴发性气旋的最大加深率为1.7Bergerons，其下垫面经历的“海洋-陆地-海洋”的复杂变化对其发展过程产生了显著影响。该气旋登陆朝鲜半岛时，气温降低，水平风速减小，上升运动增强，降水增加；而离开朝鲜半岛后，气温升高，上升运动减弱，降水减少。海陆差异的敏感性试验表明，陆地下垫面对气旋发展的动力作用主要是通过地面摩擦和地形抬升来实现的，而海洋对气旋发展的作用则主要表现在海表面热量和水汽传输方面。当气旋经过陆地时，由于陆地表面摩擦较大，气旋中心近地面水平风速减小。而较高的地形则会产生较强的上升运动，形成较强降水，促进类CISK（Conditional Instability of Second Kind）机制，使气旋加强。当气旋位于海面上时，冬季海面温度高于陆地，海洋向气旋输送更多的热量和水汽，从而更有利于气旋的发展。 |
| 关键词: 爆发性气旋 海陆差异 WRF模式 敏感性试验 |
| DOI：10.11693/hyhz20200200045 |
| 分类号:P732.2 |
| 基金项目:广东海洋大学“创新强校工程”科研项目，230419106号；广东海洋大学大学生创新训练项目，580520052号；广东海洋大学“创新强校”资助项目，230419053号；广东海洋大学科研启动费资助项目，R19045号。 |
附件 |
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| THE IMPACT OF SEA-LAND DIFFERENCE ON A STRONG EXPLOSIVE CYCLONE USING NUMERICAL SIMULATION |
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GAO Xiao-Yu1, TANG Ruo-Ying2, ZHANG Shu-Qin3, CHEN Jin-Long4, Xu Hong-Lei5
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1.Department of Earth System Science, Tsinghua University, Beijing 100081, China;2.College of Agriculture, Guangdong Ocean University, Zhanjiang 524088, China;3.College of Oceanography and Meteorology, South China Sea Institute of Marine Meteorology, Guangdong Ocean University, and Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang), Zhanjiang 524088, China;4.92020 Unit of the People's Liberation Army of China, Qingdao 266100, China;5.91208 Unit of the People's Liberation Army of China, Qingdao 266100, China
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| Abstract: |
| A strong explosive cyclone happened off East China coast during Dec. 23–25, 2017 was studied using multiple observation and reanalysis data in WRF model. The cyclone was intensified after moving into the ocean. The effects of land-and-sea topography and thermal difference on the development of the explosive cyclones were explored. The highest deepening rate of the cyclone was >1.7Bergerons, and the underlying surface experienced a complicated “sea-land-sea” transform, which had an important impact on the explosive developing process. When the cyclone landed on the Korean Peninsula, air temperature decreased, horizontal wind was weakened, ascending motion was strengthened, and precipitation increased. When the cyclone left the peninsula, air temperature increased, ascending motion was weakened, and precipitation decreased. Results of the sensitivity experiments of sea-land differences indicate that the dynamic effects of land manifested as ground friction and topographic uplift. Stronger surface friction of land led to weaker horizontal wind, while the increasing topography led to a stronger ascending motion, producing more precipitation, which promoted the positive feedback mechanism similar to CISK and deepened the cyclone. The thermal effects of sea manifested as heat and water vapor transport over the sea surface. The temperature of sea surface was higher than that of land surface, so that the ocean could transport more heat and vapor to the cyclone, which was more favorable for the development of cyclones. |
| Key words: explosive cyclone sea-land difference WRF model sensitivity experiment |
