The Vertical Profile of Ocean Mixing

Monday, 15 December 2014: 10:35 AM
Raffaele M Ferrari1, Maxim Nikurashin2, Trevor J McDougall3 and Alizera Mashayek1, (1)Massachusetts Institute of Technology, Cambridge, MA, United States, (2)Princeton University, Princeton, NJ, United States, (3)University of New South Wales, Sydney, Australia
The upwelling of bottom waters through density surfaces in the deep ocean is not possible unless the sloping nature of the sea floor is taken into account. The bottom‐‑intensified mixing arising from interaction of internal tides and geostrophic motions with bottom topography implies that mixing is a decreasing function of height in the deep ocean. This would further imply that the diapycnal motion in the deep ocean is downward, not upwards as is required by continuity. This conundrum regarding ocean mixing and upwelling in the deep ocean will be resolved by appealing to the fact that the ocean does not have vertical side walls. Implications of the conundrum for the representation of ocean mixing in climate models will be discussed.