Turbulent mixing in a changing Arctic Ocean

• Published in: Oceanography
• Main Authors: Rippeth, Tom, Fine, Elizabeth
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: Arctic; Arctic Ocean; Sea ice
• Online Access: https://research.bangor.ac.uk/portal/en/researchoutputs/turbulent-mixing-in-a-changing-arctic-ocean(eca8f564-6de3-4bb7-8831-69dea9ce55b1).html; https://research.bangor.ac.uk/ws/files/41346330/35_rippeth.pdf; https://doi.org/10.5670/oceanog.2022.103

The Arctic Ocean has traditionally been thought of as an ocean of low variability and weak turbulent mixing which does not play a significant role in the evolution of water masses. However, with the recent decline in seasonal sea ice cover has led to increased coupling between the atmosphere and ocean potentially greatly enhancing turbulent mixing (Rainville et al., 2011). Here we review work carried out over the past decade to assess the changing impact of turbulent mixing in an increasingly ice-free Arctic Ocean. We find the evolution of wind generated near-inertial oscillations is highly sensitive to the seasonal cycle in sea ice, but that the response varies greatly between the eastern and western Arctic basins due to differing levels of halocline stratification. There is increasing interest in the role of the tides in driving mixing over sloping topography and of far-field storms via continental shelf waves. Both dissipate through the development of unsteady lee-waves. The role of eddies in transporting shelf water into the basins and in supporting mixing has also come under increased focus as sea ice retreat and technological advances have permitted higher resolution observation. The key role of these processes highlight the need for mixing associated with unsteady lee waves and eddies to be parameterised for inclusion in region ocean models and climate simulations.