Gravity currents in the ocean occur where large horizontal gradients in density, due to either temperature or salinity variations, generate buoyancy-driven currents. In the coastal ocean, they are found in estuaries, river plumes, and around complex coastline topography. In the deep ocean, they occur where cold dense water sinks at high latitudes, and consequently are a key driver of the global ocean circulation. Gravity currents generate turbulence and internal waves and play an important role in the mixing between water masses with different origins, chemical signatures, and biological components. This project was funded by a grant from the National Science Foundation Physical Oceanography program.

 

Single_Waves

A buoyant gravity current generating a packet of internal solitary waves in a sharply stratified ambient fluid. (2D numerical simulation, from White & Helfrich 2012).