Max Nikurashin,  Princeton University

Time and date: 12:00 – 12:50 pm, Wednesday 19 Oct
Venue: Seminar room, IMAS Sandy Bay

Abstract:
The wind power input into the ocean is dominated by the work done in the Southern Ocean where it drives the Antarctic Circumpolar Current system and is eventually converted, through baroclinic instability, into a vigorous geostrophic eddy field. Kinetic energy of the entire ocean is dominated by the geostrophic eddies. While the energy input into geostrophic eddy field is well understood, energy transfer mechanisms from eddies to turbulence and dissipation remain unclear. Recent estimates from observations indicate that turbulent mixing associated with internal wave breaking is enhanced above rough topography in the Southern Ocean. Using numerical simulations, observations, and linear theory, I will argue in this talk that enhanced abyssal mixing in the Southern Ocean can be sustained by internal waves generated by geostrophic eddies flowing over rough topography. High-resolution eddy simulations with rough topography also suggest that the eddy-topography interaction is a significant energy sink for the geostrophic flows as well as an important energy source for internal waves and the associated turbulent mixing in the deep ocean.

Biography:
Max (Maxim) Nikurashin is a physical oceanographer, currently employed as an Associate Research Scholar at the Princeton University Program in Atmospheric and Oceanic Sciences. Max received his MS and BS in Applied Physics and Mathematics, Moscow Institute of Physics and Technology in 2002 and a PhD from the MIT/Woods Hole Joint Program in 2008.

Max’s research interests are in the area of Physical Oceanography and span problems ranging from internal waves and mixing at small scales to the maintenance of stratification and overturning circulation of the ocean at large scales. He uses a combination of theory, process oriented numerical simulations, and observations to understand fundamental processes in the ocean and their impact on the global circulation and climate.