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

本研究将以飞机和多普勒雷达资料为主要资料，通过中尺度观测分析，探讨对流和层状过程对热带气旋强度变化的影响。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，相对于最大风半径（RMW）的深对流爆发和层状降水的径向位置可能对增强效率起重要作用。需要利用中尺度观测对这些新假设进行检验，以诊断导致强度变化的最重要物理过程，并改进TC强度预报。智力优势：分析多普勒雷达、落差探空仪、卫星和其他观测将用于检查TC对流和层状结构，它们的热力学和动力环境，以及它们对TC环流的影响。以往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。在RMW外，与层状降水相关的中层流入可以有效地通过摩擦边界层上方绝对角动量的辐合使更广泛的环流旋转起来。该研究将利用现有的研究观测，在TC生命周期的不同阶段，从强化风暴和非强化风暴，来检验这些假设。由首席研究员开发的一种名为SAMURAI的新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进行分析。利用改进的雷达热力学检索进行高分辨率笛卡尔和低波数圆柱分析，并辅以数值模拟，以提高我们对TC增强的理解。更广泛的影响：本研究将研究和教育结合起来，开发了一门新的研究生雷达气象学课程，其中包括数字互动教科书，并将中尺度TC观测纳入物理气象学课程，以训练和鼓励学生使用实地观测来检验科学假设。开放源代码的SAMURAI分析软件和数字雷达气象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将妇女和代表性不足的少数民族（如太平洋岛民和夏威夷原住民）纳入该项目来改善多样性。提高我们对TC强度变化的理解可以对社会产生重大的积极影响。对飓风和台风的持续研究成果的应用，最终将有助于提高我们的预报能力，减少全球范围内的生命和财产损失。

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.