北大西洋爆发性气旋的研究

Explosive cyclone refers to the rapidly-developing cyclonic system that has the maximum deepening rate of central pressure greater than 1hPa/h and the sea level wind speed greater than 25m/s. As explosive cyclones often cause severe weather such as strong wind and heavy rainfall/snowfall, they are thought to be one of the most dangerous weather systems. They frequently occurred over the Northern Atlantic in cold season, and had complicated spatial-temporal structures as well as development mechanisms. This program aims to study explosive cyclones over the Northern Atlanic by using almost all available observational data during the recent 20-year (1997-2017), such as FNL (Final Analyses, 1°× 1°), CFSR (Climate Forecast System Reanalysis, 0.5°×0.5°), ECMWF(European Centre for Medium-Range Weather Forecasts) ERA-Interim (0.25°×0.25°), COSMIC (The Constellation Observing System for Meteorology, Ionosphere, and the Climate), MTSAT-1 (Multifunctional Transport the Satellite-1) infrared satellite data, MODIS (Moderate-resolution Imaging, Spectroradiometer) visible satellite data, as well as the coupled ocean-atmosphere model of WRF (the Weather Research and Forecasting model) / ROMS (the Regional the Ocean model System). The main contents include: (1) Relationship between the moving tracks, the spatial-temporal structures of various explosive cyclones over the Northern Atlantic and the large-scale atmospheric and oceanic environments in cold season; (2) Comparative analyses of different development mechanisms of various explosive cyclones over the Northern Atlantic; (3) Influences of sea surface temperature field and the diabatic heating field on the development mechanisms of various explosive cyclones over the Northern Atlantic; (4) Structures and evolutionary processes of the frontal system associated with various explosive cyclones over the Northern Atlantic; This program seeks to enhance a deeper understanding on the development mechanisms of various explosive cyclones over the Northern Atlantic, and has important academic and practical value to ensure the maritime navigation safety over the Northern Atlantic.

爆发性气旋是指气旋中心气压加深率大于1hPa/h, 且至少有一个时刻的海表面最大风度大于25m/s的气旋系统。本项目拟利用近20年(1997年-2017年)来的最新观测资料,如FNL, CFSR, ECMWF ERA-Interim, COSMIC, MTSAT-1和MODIS 卫星资料, 以及WRF/ROMS 海气耦合模式, 采用资料分析、数值模拟和理论研究相结合的研究手段，开展近20年来北大西洋(100°W-10°E,20°N-80°N)爆发性气旋的时空演变特征及发展机理研究。主要内容有：(1)爆发性气旋的移动路径、时空结构与大尺度大气和海洋环境场关系研究；(2)爆发性气旋不同发展机理的分析比较；(3)海表面温度场和非绝热加热场对爆发性气旋发展机理影响的研究；(4)爆发性气旋所伴随的锋面系统结构和演变过程研究。本项目对于提高对北大西洋爆发性气旋的认识水平具有重要的学术和实践价值。

“爆发性气旋” (explosive extratropical cyclone),是在冷季中高纬度海洋上迅猛发展的温带气旋,也被学者们称为“气象炸弹” (meteorological bomb),具有短时间内中心气压迅速降低、强度急剧增大的特点,其发展机理一直是国际学术界关注的前沿问题之一。申请人从2018年开始在国家自然科学基金《北大西洋爆发性气旋的研究》(41775042)的支持下,利用2000年以后的最新观测资料和卫星资料,采用资料分析、数值模拟和理论研究相结合的研究手段,开展北大西洋(100°W-10°E, 20°N-80°N)上爆发性气旋的时空演变特征及发展机理研究。取得以下主要研究成果：(1)对1979年至2016年共3916个爆发性气旋的初始生成经度、纬度、初始生成时刻、生命史、中心最低气压、最大加深率时刻、最低中心气压时刻、移动路径等信息进行了登记。(2)修正了爆发性气旋的传统定义,即不仅考虑气旋中心气压要在24小时内下降达到24hPa以上,而且10m高度上最大风速要大于17.2m/s。(3) 分析了北大西洋爆发性气旋的时空结构及典型个例的演变特征, 并对与爆发性气旋关系密切的东亚地区“大气河”时空结构进行了初步分析。(4) 出版学术专著《爆发性气旋》一部(2021年,科学出版社, ISBN:978-7-03-071058-1),在国内外学术刊物上发表论文25篇,还有2篇论文已定稿,1篇英文论文在修改中,1篇英文论文已投稿。已发表论文总数为原设定目标数(10篇)2倍多。(5)培养毕业博士研究生2人(张树钦、孙雅文),硕士研究生6人(刘珊、井苗苗、李昱薇、张雪贝、孙柏堂、宋佳凝),还有1名博士研究生(陈莅佳)和5名硕士研究生(鄢珅、倪晶、彭永茂、王忠石、孙维康)在读。无论是培养研究生的数量、还是发表论文的数量都全面超额完成了本基金项目设定的目标。