Scientists from Brown University have constricted a new statistical model, designed to improve the understanding by scientists of how turbulent flows termed mesoscale eddies dissipate energy. The study shows that the majority of the dissipation happens in relatively sparse locales around the globe. This model will be helpful in creating better ocean and climate models to assess changes to the planet.
With the research, the physicists looked at a form of turbulence refereed to as mesoscale eddies. In fluid dynamics, an eddy is the swirling of a fluid and the reverse current created when the fluid is in a turbulent flow regime. In terms of the seas, these eddies are ocean swirls that occur on the scale of tens to hundreds of kilometers across, and they last for up to one year. These specific eddies tend to pinch off from strong boundary currents such as the Gulf Stream. Alternatively they can form where water flows of different temperatures and densities come into contact.
Studying these eddies is significant, according to lead scientist Professor Baylor Fox-Kemper: “You can think of these as the weather of the ocean. Like storms in the atmosphere, these eddies help to distribute energy, warmth, salinity and other things around the ocean. So understanding how they dissipate their energy gives us a more accurate picture of ocean circulation.”
To assess the eddies, the research group developed a high-resolution ocean model based on direct satellite observations of the global ocean system. The model was able to simulate eddies on the order of 100 kilometers across. The model was run for five years. Based on the model the researchers will be able to develop coarser-grained ocean simulations that will reveal changes to the planet’s climate.
The research has been published in the journal Physical Review Letters, with the peer reviewed paper headed “Log-Normal Turbulence Dissipation in Global Ocean Models.”
