Refraction and Reflection of Nonlinear Internal Waves from Steep Topography
Abstract
Approved for Public Release - Internal waves are an important mechanism of energy transfer from tides and winds driving mixing whi,ch shapes the stratification and circulation of the ocean with important implications for climate. Large amplitude, nonlinear intern,al waves (NLIWs) can induce strong currents, upwell dense water high in nutrients, and also affect marine operations and acoustic co,mmunications. The processes that determine generation and propagation of NLIWs have been the focus of extensive research. The bulk o,f work addressing NLIW transformation as they interact with topography, including shoaling and breaking, has largely focused on 2D t,opography. A number of remote sensing studies have noted significant redirection of NLIW energy associated with steep 3D topography,, however. The dynamics of NLIW refraction around steep topographic features is not yet well-understood. Here, we propose to explore, processes that determine NLIW transformation over steep, 3D topography - including refraction, shoaling and reflection along with, the implications of these processes on the internal wave environment at larger scales. The broad objective for the project is to im,prove forecasting and predictability for nonlinear internal waves in the ocean. The proposed work will make use of high resolution n,umerical simulations combined with analysis of existing observational data to examine the effects of wave characteristics, flow hist,ory, local internal tides and changes in rotation on NLIW transformation and on subsequent generation of residual circulation and tr,apped baroclinic energy. Results from the numerical experiments will be used to guide a set of focused field observations to be car,ried out at Dongsha Atoll, a steep, nearly circular feature in the South China Sea. Extensive work has previously been carried outo,n NLIWs in this region, where some of the largest internal waves on the planet have been observed. The modeling work and field obser,vations build on long-standing collaborative efforts between the project PIs, Taiwanese colleagues and other ONR supported researche,rs. The proposed field observations, in particular, are expected to be carried out in collaboration with researchers in Taiwan.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 14, 2022
- Source ID
- N000142212040
Entities
People
- Kristen A. Davis
Organizations
- Office of Naval Research
- United States Navy
- University of California, Irvine