Connections between the large-scale flow and turbulence in the Samoan Passage

Jesse Cusack1, Gunnar Voet2, Matthew H Alford1, James B Girton3, Glenn S Carter4, Lawrence J Pratt5, Shuwen Tan6, Kelly Pearson7 and Dimitris Menemenlis8, (1)Scripps Institution of Oceanography, La Jolla, CA, United States, (2)Scripps Institution of Oceanography, La Jolla, United States, (3)University of Washington, Applied Physics Laboratory, Seattle, WA, United States, (4)University of Hawaii at Manoa, Oceanography, Honolulu, HI, United States, (5)Woods Hole Oceanographic Institution, Physical Oceanography, Woods Hole, United States, (6)Institute of Oceanology, Chinese Academy of Sciences, Qungdao, China, (7)University of Hawaii at Manoa, Honolulu, HI, United States, (8)NASA Jet Propulsion Laboratory, Pasadena, United States
Abstract:
Abyssal waters flow equatorward along the western margin of the South Pacific basin and into the North Pacific via the Samoan Passage. Within the Passage, interaction of this flow with topographic features leads to intense mixing. The basin-scale physical processes that influence the volume flux into the Passage will be explored using a 1/48th degree ocean state estimate (ECCO LLC4320). To illustrate how the turbulent dissipation rate changes in response to changes in large scale forcing, idealized 2-D numerical simulations of flow over the topography within the Passage will also be presented. Model results will be discussed in the context of extensive observation-based estimates of dissipation rates and their variability throughout the Passage.