Toward Improved Understanding of Rapid Intensification (RI) of Tropical Cyclones

加深对热带气旋快速增强 (RI) 的了解

• 批准号: 1326524
• 负责人: Yuqing Wang
• 金额: $ 30.35万
• 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: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1326524&HistoricalAwards=false
• 关键词: Toward; Improved; Understanding; Rapid; Intensification

The rapid intensification (RI), which involves interactions between the inner core dynamics and the large-scale environment and among different spatial and temporal scales, is still one of the least understood phases of a tropical cyclone (TC). Previous studies have already shown that the rapid formation of a warm core in the upper troposphere is the key to the RI onset of a TC. In this study, processes that lead to the rapid formation of the upper-tropospheric warm core in TCs will be explored through on idealized and real-case simulations and diagnostic and budget analyses using cloud-resolving models. In particular, the following three scientific questions will be addressed:1) Given favorable tropical ocean conditions, is the intensification rate of a TC externally or internally determined and can an environmental flow or synoptic-scale forcing increase the intensification rate that a TC could have without these forcing?2) How do the three-dimensional (3D) structure (including the size) and intensity of a TC vortex determine the efficiency of the upper-tropospheric warming and thus the intensification rate of the TC itself?3) How are convective bursts and hot towers triggered and how do they lead to the upper tropospheric warming over the storm core prior to and during the RI?To answer these questions, we will use the TC model (TCM4) developed by the PI and the advanced Weather Research and Forecasting (WRF) model developed at National Center for Atmospheric Research (NCAR) to conduct a series of idealized and real-case simulations and perform diagnostic and budget analyses to verify our hypotheses, identify the physical mechanisms responsible for the RI. Intellectual Merit:Results from this research will improve our understanding of the dynamics of the RI of tropical cyclones and factors that determine the potential intensification rate of a TC.Broader Impacts:The research will lead to a set of parameters/factors that determine the potential intensification rate of tropical cyclones. This will contribute to improved ability to predict TC intensity change. Results from this research will also demonstrate what parameters of the three-dimensional structure of the initial TC are critical to the intensity prediction by numerical models, thus potentially leading to improved prediction of TC structure and intensity. In the course of this project, a female graduate student will receive training in the science of TCs, especially in the area of TC dynamics and modeling.

热带气旋的快速增强（RI）涉及到内核动力学与大尺度环境之间以及不同时空尺度之间的相互作用，至今仍是人们对热带气旋（TC）了解最少的阶段之一。 以往的研究已经表明，对流层上层暖核的快速形成是热带气旋RI爆发的关键。 在这项研究中，将通过使用云解析模型的理想化和真实情况模拟以及诊断和预算分析来探索导致TC中上层对流层暖核快速形成的过程。 特别是，以下三个科学问题将得到解决：1）给定有利的热带海洋条件下，是外部或内部确定的TC的强化率和环境流或天气尺度强迫可以增加TC可能没有这些强迫的强化率？2)TC涡旋的三维结构（包括大小）和强度如何决定对流层上层增暖的效率，从而决定TC本身的增强率？3)对流爆发和热塔是如何触发的，它们是如何导致RI之前和RI期间风暴核心上方对流层上层变暖的？为了回答这些问题，我们将使用PI开发的TC模式（TCM 4）和美国国家大气研究中心（NCAR）开发的高级天气研究和预报（WRF）模式进行一系列理想化和真实情况下的模拟，并进行诊断和预算分析，以验证我们的假设，确定负责RI的物理机制。智力优点：这项研究的结果将提高我们对热带气旋RI的动态和决定TC潜在强化率的因素的理解。更广泛的影响：这项研究将导致一组参数/因素，决定热带气旋的潜在强化率。 这将有助于提高预测TC强度变化的能力。 从这项研究的结果也将证明初始TC的三维结构的参数是至关重要的强度预测的数值模式，从而可能导致改进的TC结构和强度的预测。在该项目的过程中，一名女研究生将接受TC科学方面的培训，特别是TC动力学和建模方面的培训。