North Atlantic Tropical Cyclone Genesis Pathways

该项目由2009年《美国复苏和再投资法》（公法111-5）资助，将利用目前计划于2010年8月和9月进行的热带地区云系大萧条前调查（PREDICT）现场实验提供的机会，调查北大西洋热带气旋（TC）的前期和成因。这项工作的动机是以前的研究，确定了六个不同的客观定义的北大西洋TC成因途径。 拟议研究的一个独特方面是TC成因/零事件将根据先前确定的六条成因路径分层，并在几个完整的TC季节进行分析，以帮助揭示独特的路径依赖动力学特征。项目任务将是：（i）建立最近北大西洋热带气旋季节的热带气旋气候学（不只是TC病例，因为无效事件很重要，并且将超过TC发展）;（二）通过分析最近北大西洋热带气旋季节，开发一个诊断参数，指示一个地区的首选成因途径，供预测期间使用，并确定（iii）在PREDICT之前和期间对TC成因/零事件进行详细的诊断分析，以确定成因路径依赖的控制物理关系;（iv）使用集合卡尔曼滤波器（EnKF）技术创建成因路径复合分析集合，以突出路径依赖的环境特征和动态重要特征和关系;及（v）在PREDICT期间进行原型TC事件的高分辨率模式研究，以评估路径依赖模式的敏感性。在智力价值标准方面，研究将通过分离控制TC沿着个别成因路径发展的各种环境和动力因素，建立适用于个别TC成因路径的主导动力和动力过程，在更广泛的影响标准方面，科学认识方面的预期进展将转化为对北方TC成因的中期和短期预报的改进;有助于对该项目支助的两名研究生进行专门研究培训和高等教育;丰富和提高PI及其同事在天气动力学和热带气象学领域的教学和学术研究。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This project will use the opportunity afforded by the PRE-Depression Investigation of Cloud-systems in the Tropics (PREDICT) field experiment, currently planned for August and September 2010, to investigate the pre-genesis and genesis of North Atlantic tropical cyclones (TCs). The proposed work is motivated by previous research that identified six distinct objectively defined North Atlantic TC genesis pathways. A distinctive aspect of the proposed research is that TC genesis/null events will be stratified by the six previously identified genesis pathways and analyzed over several complete TC seasons to facilitate uncovering distinctive pathway-dependent dynamical signatures.The project tasks will be: (i) construct a TC climatology over recent North Atlantic TC seasons (not justTC cases since null events are important and will outnumber TC developments) for each of the identified six genesis pathways;(ii) develop a diagnostic parameter indicating the preferred genesis pathway in a region from analysis of recent North Atlantic TC seasons for use during PREDICT and establish which genesis parameters are important for TC development depending on genesis path;(iii) perform detailed diagnostic analyses of TC genesis/null events prior to and during PREDICT to identify genesis pathway-dependent governing physical relationships;(iv) create genesis pathway composite analysis ensembles using ensemble Kalman filter (EnKF) techniques to highlight pathway-dependent environmental signatures and dynamically important features and relationships; and (v) conduct high-resolution modeling studies of archetype TC events during PREDICT to evaluate pathway-dependent model sensitivity.With respect to the intellectual-merit criterion, the research will advance scientific understanding by isolating the various environmental and dynamical factors that control TC development along individual genesis pathways; establishing the governing dynamical and thermodynamical processes applicable to the individual TC genesis pathways; and increasing our understanding of the physical mechanisms that control TC predictability and error growth along different genesis pathways.With respect to the broader impact criterion, the anticipated advances in scientific understanding will translate into improved medium- and short-range forecasts of TC genesis over the North; contribute to the specialized research training and advanced education of the two graduate students to be supported by this project; and enrich and enhance the teaching and scholarship of the PI and his colleagues in the areas of synoptic-dynamic and tropical meteorology.