CAREER: Impacts of Convective and Stratiform Processes on Tropical Cyclone Intensity Change

职业：对流和层状过程对热带气旋强度变化的影响

• 批准号: 1349881
• 负责人: Michael Bell
• 金额: $ 78.33万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2016-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1349881&HistoricalAwards=false
• 关键词: CAREER; Impacts; Convective; Stratiform; Processes

This study will investigate the impacts of convective and stratiform processes on tropical cyclone (TC) intensity change through analysis of mesoscale observations, with a focus on aircraft and Doppler radar data. Our ability to skillfully predict changes in TC intensity is still limited, but recent studies have suggested that the radial location of deep convective bursts and stratiform precipitation relative to the radius of maximum wind (RMW) may play an important role in intensification efficiency. Testing these new hypotheses using mesoscale observations is needed to diagnose the most important physical processes responsible for intensity change and improve TC intensity forecasts.Intellectual Merit:Analysis of Doppler radar, dropsonde, satellite, and other observations will be used to examine TC convective and stratiform structures, their thermodynamic and dynamic environment, and their impacts on the TC circulation. Previous theoretical and numerical studies have suggested that convective heating and associated low-level convergence inside the RMW can efficiently intensify the maximum winds. Outside the RMW, mid-level inflow associated with stratiform precipitation can efficiently spin-up the broader circulation through convergence of absolute angular momentum above the frictional boundary layer. The research will use existing research observations at different stages of the TC lifecycle from intensifying and non-intensifying storms to test these hypotheses. A new variational analysis technique called SAMURAI developed by the Principal Investigator will be used to integrate aircraft and radar observations into three-dimensional thermodynamic and kinematic fields for analysis. High-resolution Cartesian and low-wavenumber cylindrical analyses with improved radar thermodynamic retrievals will be conducted and augmented with numerical simulations to improve our understanding of TC intensification.Broader Impacts:This study integrates research and education by developing a new graduate radar meteorology course with a digital, interactive textbook, and incorporating mesoscale TC observations into physical meteorology curricula to train and encourage students to test scientific hypotheses using field observations. The open source SAMURAI analysis software and material from the digital radar meteorology textbook will be available to the atmospheric science community to enhance research and education infrastructure. The University of Hawaii at Manoa represents a demographically and geographically unique state in an EPSCoR jurisdiction, and the Principal Investigator is committed to improving diversity by including women and underrepresented minorities such as Pacific Islanders and Native Hawaiians in the project. Improvements in our understanding of TC intensity change can have a significant positive impact on society. The application of the findings from continued research on hurricanes and typhoons can ultimately help to improve our forecast ability and reduce life and property loss throughout the globe.

本研究将通过分析中尺度观测，重点关注飞机和多普勒雷达数据，研究对流和层状过程对热带气旋（TC）强度变化的影响。我们熟练预测TC强度变化的能力仍然有限，但最近的研究表明，深对流爆发和层状降水相对于最大风半径（RMW）的径向位置可能在强化效率中发挥重要作用。需要使用中尺度观测来测试这些新假设，以诊断导致强度变化的最重要的物理过程，并改进热带气旋强度预报。智力价值：分析多普勒雷达、下投式探空仪、卫星和其他观测数据将用于检查热带气旋对流和层状结构、它们的热力学和动力环境以及它们对热带气旋环流的影响。先前的理论和数值研究表明，RMW 内部的对流加热和相关的低层辐合可以有效地增强最大风速。在 RMW 之外，与层状降水相关的中层流入可以通过摩擦边界层上方绝对角动量的收敛有效地旋转更广泛的环流。该研究将利用热带气旋生命周期不同阶段（从加强风暴到非加强风暴）的现有研究观测来检验这些假设。首席研究员开发的一种名为 SAMURAI 的新型变分分析技术将用于将飞机和雷达观测整合到三维热力学和运动学领域中进行分析。将进行高分辨率笛卡尔和低波数柱面分析以及改进的雷达热力学反演，并通过数值模拟进行增强，以提高我们对 TC 增强的理解。更广泛的影响：这项研究通过开发新的研究生雷达气象学课程和数字交互式教科书，并将中尺度 TC 观测纳入物理气象学课程来培训和培训，从而将研究和教育融为一体。 鼓励学生通过实地观察来检验科学假设。开源 SAMURAI 分析软件和数字雷达气象学教科书中的材料将提供给大气科学界，以加强研究和教育基础设施。夏威夷大学马诺阿分校代表了 EPSCoR 管辖范围内人口和地理上独特的州，首席研究员致力于通过在项目中纳入妇女和代表性不足的少数群体（如太平洋岛民和夏威夷原住民）来提高多样性。提高我们对热带气旋强度变化的认识可以对社会产生重大的积极影响。应用对飓风和台风持续研究的结果最终可以帮助提高我们的预测能力并减少全球范围内的生命和财产损失。