The TRR 181 seminar is held by Joel Bracamontes Ramírez (MARUM - University of Bremen) on November 3, 11 am.

Internal Waves in the Arctic Ocean: Effect of the stratification

Abstract

The stratification in the Arctic Ocean is quite unique. It is strong in the upper layers within the halocline, and weak close to the bottom within a homogeneous bottom layer. Furthermore, thermohaline staircases are found across the Arctic Basins at mid-depth and in the abyss. Those density structures affect mixing and wave propagation, or act as a filter for internal waves. Even though the Arctic Ocean’s wave climate is currently quiescent, wind-driven internal wave activity is expected to increase with the shrinking sea ice cover. Therefore, it is important to understand how the stratification affects internal wave propagation. Here, we present two effects of stratification on internal waves. First, through data analysis, we characterized near-inertial turning depths in the Canadian Basin, a depth at which buoyancy frequency is lower than the local Coriolis frequency.
Second, numerical simulations of internal wave propagation through density staircases illustrate a novel transmission mechanism in which an incoming wave excites interfacial waves within the staircase that slowly leak energy above and below the staircase.