Collaborative Research: The Relationships between Sheared Convective Clouds and Tropical Cyclone Evolution

尽管观测和计算资源有所改善，但热带气旋结构和强度演变的预报仍然是一个重大挑战。可预测性的限制涉及到一个TC的多尺度动力学和它的环境之间的非线性相互作用。最近的研究强调了TC的演化是如何受到潜热细节的强烈影响的。因此，正确地解释tc中的对流过程是对tc进行更完整的物理理解和改进预测的关键一步。然而，对流尺度动力学的潜在基本方面仍未得到解决。在tc中发现的运动学和热力学性质的详细结构可以提供广泛的不同局部环境，从而产生各种对流和中尺度云形态。每一种对流模式对TC的演变可能有独特的影响。知识价值：为了促进对对流尺度过程的理解，这项多框架研究将研究垂直和水平风切变与孤立对流云和更有组织的雨带的相互作用。通过这项研究的努力，将检查以下问题：1。强水平风切变和背景绝对垂直涡度如何影响孤立对流云和雨带？在水平和垂直剪切和对流之间发生的主要相互作用是什么？对流对三维切变的响应如何随tc内环境热力学条件的变化而变化？由运动学和热力学变化引起的各种对流模式对整体TC动力学的影响是什么？本研究的多个框架将包括一个理想的云模型、高分辨率飞行水平多普勒雷达和TC的现场观测，以及两个全物理TC模拟。云模型的敏感性实验将用于了解tc内的三维风切变和热力学变率如何控制孤立的对流云和对流系统。剪切对流对平均气流的影响也将记录在云模式中。观测分析和TC模拟将提供真实的环境来评估理想的云模拟结果，并推断各种剪切对流模式、雨带和TC动力学之间的反馈和关系。涡度、位涡度、热力学预算以及云、降水和冷池性质的一般统计分析将成为阐明与剪切TC对流相关的开放性问题的主要分析工具。更广泛的影响：本研究将揭示与TC强度和结构变化相关的基本内部动力学过程，并将在TC研究之外产生更广泛的理论影响。由此产生的同行评审出版物将提供应用和理论背景，研究人员和预报员可以在其中解释对流尺度过程。改进对热带气旋和热带气旋中的对流尺度过程的预测将对社会有益。研究小组将与飓风加强和登陆调查中心以及有才华和积极进取的本科生/研究生合作，他们将为研究的重要方面和随后的同行评审出版物做出贡献。一个包含关键实验结果动画的网页将补充研究文章，也将有助于大学课堂教学和其他推广工作，如科学高中讲习班。

Despite improving observational and computational resources, the forecasting of tropical cyclone (TC) structural and intensity evolution is still a significant challenge. The limits of predictability relate to the nonlinear interactions between a TC's multi-scale dynamics and its environment. Recent research underscores how TC evolution is influenced strongly by the details of latent heating. As such, properly accounting for convective processes in TCs is a key step towards a more complete physical understanding of TCs and improved prediction. Yet, potentially essential aspects of convective-scale dynamics remain unresolved. The detailed structure of kinematic and thermodynamic properties found within TCs can provide a broad spectrum of distinct local environments resulting in a variety of convective and mesoscale cloud morphologies. Each convective mode may have unique impacts on TC evolution.Intellectual merit:To advance the understanding of convective-scale processes in TCs, this multi-framework study will investigate the interactions of vertical and horizontal wind shear with both isolated convective clouds and more organized rainbands. Through this research effort, the following questions will be examined:1. How do strong horizontal wind shear and background absolute vertical vorticity impact isolated convective clouds and rainbands?2. What are the primary interactions that occur between horizontal and vertical shears and convection?3. How does the response of convection to three-dimensional shear vary given the variations of ambient thermodynamic conditions within TCs?4. What are the implications of the various convective modes resulting from kinematic and thermodynamic variability on overall TC dynamics?The multiple frameworks for this study will include an idealized cloud model, high-resolution flight-level Doppler radar and in situ observations of TCs, and two full-physics TC simulations. Sensitivity experiments with a cloud model will be used to understand how three-dimensional wind shear and thermodynamic variability within TCs govern isolated convective clouds and convective systems. The impacts of sheared convection on the mean flow will also be documented in the cloud model. The observational analyses and TC simulations will provide realistic settings to evaluate the idealized cloud modeling results and to deduce feedbacks and relationships between the various sheared convective modes, rainbands, and TC dynamics. Vorticity, potential vorticity, and thermodynamic budgets and general statistical analysis of cloud, precipitation, and cold pool properties will be the primary tools of analysis for elucidating open questions related to sheared TC convection.Broader impacts:The research will shed new light into basic internal dynamical processes related to TC intensity and structure change and it will have more general theoretical impacts outside of TC research. The resulting peer-reviewed publications will provide both applied and theoretical contexts in which both researchers and forecasters can interpret convective scale processes in TCs. Improvement in forecasting TCs and convective-scale processes in TCs will in turn be beneficial to society. The research team will work with the Center for Hurricane Intensification and Landfall Investigation and talented and motivated undergraduate/graduate students who will contribute to significant aspects of the research and subsequent, peer-reviewed publications. A webpage containing animations of key experimental results will supplement research articles and will also aid in college classroom instruction and other outreach efforts such as scientific high school workshops.