Does Mixing around Seamounts Drive Upwelling or Downwelling?

Hosts: Henri Drake and Sonya Legg

The ocean overturning circulation controls Earth’s climate by exchanging heat, carbon, and nutrients between the deep ocean and the surface ocean or atmosphere. While the localized high-latitude processes that contribute to the downwelling branch of this circulation have long been identified, the opposing upwelling branch remains relatively poorly characterized. Dynamical theory demonstrates that small-scale turbulent mixing is the only plausible driver of the upwelling branch of the circulation, but where these hotspots are and the efficiency with which this mixing translates into upwelling is hotly debated. Isolated underwater mountains, known as seamounts, are one possible site of elevated mixing, but experts differ on whether such mixing would lead to upwelling or downwelling in the net.

The goal of this project is to run idealized computer simulations of mixing-driven flow around seamounts to determine how vertical transport (upwelling or downwelling) scales with seamount geometry, mixing characteristics, and the surrounding ocean environment. The potential candidate will work with the project mentors to a) learn about ocean dynamics and numerical modeling, b) modify simulation source code to run their own numerical experiments, c) explore ocean model output by computing flow diagnostics and making flow visualizations.

Potential candidates should have an interest in oceanography, physics, math, mechanical engineering, and/or scientific computing. Experience in computer programming (for example using Python, MATLAB, or Fortran) will be very helpful.