Award: OCE-1434327

Award Title: Collaborative Research: A study of the energy dissipation of the internal tide as it reaches the continental slope of Tasmania.
Funding Source: NSF Division of Ocean Sciences (NSF OCE)
Program Manager: Baris M. Uz

Outcomes Report

The T-Beam project used a combination of observations and computer simulations to understand how the internal tide is altered as it propogates across the Tasmain Sea. The Tasman Sea is a perfect laboratory for this kind of study because it contains one of the most energetic and focused internal-tide "beams" in the world. The beam (which consists of oscillations that move through the deep ocean as waves) is generated south of New Zealand, propagates 1,500 km across the Tasman Sea, and strikes the Tasman continental margin. The observations used a combination of shipboard data from a 3 week cruise on the R/V Falkor and long-term moored oceanographic instrumentation. The results from T-Beam were compared to satellite estimates of the magnitude and location of the internal tide and detailed what features were not captured by satellite observations. From the observations, we found that there was very little decay of the internal tide beam due to mixing during the internal tide's propagation across the Tasman Sea. Instead, the strength and location of the internal tide beam was more-strongly modulated by mesoscale currents. Through T-Beam, we quantified the effect ofthe mesoscale activity on the internal tide beam and presented a new parameterization that the community can use to map out the effect of the mesoscale on the internal tide. Before, during and after our field program, we conducted public outreach programs related to TBeam which included 1) numerous teleconference interviews and one-on-one correspondence also enhanced the middle school science curriculum at Los Alamos Middle School, 2) participation of four graduate students and two early-career non-PhD volunteers on the research cruise who gained technical knowledge and experience by participated in the cruise, 3) presentation of the project results to undergraduate physics majors at the University of Minnesota Duluth, Concordia College (Moorehead, MN) and Gustavus Adalphus College (St. Peter, MN), 4) contributed to an at-sea blog (https://scripps.ucsd.edu/projects/ttide/blog/) viewed by several thousand people over the course of the project, and 5) discussed physical oceanography and limnology with more than 200 elementary school students during the RN Blue Heron's " Science on Deck" open house in Duluth, MN. Last Modified: 01/13/2020 Submitted by: Jonathan D Nash

Award Home Page

NSF Research Results Report


People

Principal Investigator: Jonathan D. Nash (Oregon State University)