Mechanisms for Hurricane Motion and Intensity Change Grant

Mechanisms for Hurricane Motion and Intensity Change .

abstract

  • The factors that impact hurricane motion and intensity have been deeply studied over the past few decades, with resulting improvement in knowledge and forecasting ability. However, there are still basic questions about processes in the inner core of a hurricane and the role they may play in determining the strength and track of tropical systems. This project will focus on atmospheric waves that move around the center of a hurricane and potentially impact intensification and rain bands. The main societal impact of this work will be to improve understanding of a basic process in tropical cyclones with a goal of improving intensity and track forecasts. A student will be directly involved with the project, thus ensuring the transfer of knowledge to the next generation of scientists.The research team will conduct a theoretical and modeling study into the small-scale motions within a hurricane which may affect their direction and intensity change. The project is focused on Vortex Rossby Waves (VRWs) which can be excited by convection or tropical cyclone motion. These VRWs transport angular momentum inward and wave energy outward, and may underlie spiral rain band formation. The project will make use of two existing simple models of tropical cyclone dynamics, a linear model and a time-domain model. Four aspects of VRWs in tropical cyclones will be investigated: 1) Convectively forced wavenumber-1 VRWs and their interaction with vortex motion in a Barotropic Non-Divergent (BND) model, 2) Logical inconsistency of unbounded vortices on a spherical Earth, 3) Rectification of vorticity sources when wavenumber-n asymmetric convergence interacts with wavenumber-n vorticity to generate symmetric and wavenumber-2n vorticity, 4) Three-dimensional modeling of convectively forced waves in the inner waveguide

date/time interval

  • September 15, 2017 - August 31, 2023

administered by

sponsor award ID

  • 1724198

contributor