A Lagrangian approach to a four-dimensional understanding of the cloud-topped marine boundary layer

Abstract

The difficulties associated with measuring boundary layer characteristics in tropical cyclones are well-known, as is the necessity of understanding boundary layer dynamics for accurately forecasting storm development and intensification. In particular, rapid intensification and the corresponding linkages to air-sea fluxes, boundary layer structure, and microphysical processes remain unclear and pose a significant challenge to the Navy#s predictive capabilities due both to the complexity of these multiscale couplings as well as the practical challenges of making field observations near the ocean surface. The lack of field observations in these regimes is further confounded by the paucity of high-resolution numerical modeling in the tropical cyclone boundary layer, where turbulent fluxes, surface waves and swell, and other features such as roll vortices and marine aerosol transport are typically under-resolved or neglected.Technical breakthroughs in modeling and measurement technology provide an opportunity to move the physical understandingof the system forward in a significant way. The proposed work is intended to both complement and guide anticipated field observations made during rapidly intensifying tropical cyclones. In particular, the proposed research supports observational efforts and targets the tropical cyclone boundary layer by utilizing large eddy simulation (LES) in multiple configurations as well as existing and future (as part of this DRI) dropsonde data. Simulations designed for multiple spatiotemporal scales, including waves and microphysics, will be conducted to better understand how to plan dropsonde launches as well as interpret their data (along with any other sources of boundary layer measurement) within intensifying storms. The goal is to achieve key insight on the fundamental mechanisms of intensification, with emphasis on boundary layer structure and surface fluxes. These research activities leverage and extend ongoing expertise in the PI#sresearch group, and are intended to maximize the potential for both existing and planned observational data in tropical storms. An informal (unfunded) collaboration with Dr. George Bryan of the National Center for Atmospheric Research has been discussed, given Dr. Bryan#s experience in simulation methods and his possible involvement in a separate, independent research proposal under this DRI. Likewise, an informal (unfunded) collaboration with Dr. Dan Stern of NRL-MRY has also been discussed as well.

Document Details

Document Type
DoD Grant Award
Publication Date
Nov 09, 2024
Source ID
N000142412765

Entities

People

  • David H Richter

Organizations

  • Office of Naval Research
  • United States Navy
  • University of Notre Dame

Tags

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science/Meteorology
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Systems Analysis and Design