Extensive observations of “submesoscale” ocean eddies and their role in vertical transport.
The study area offshore of central California has been the site of many studies of submesoscale oceanic variability.
However, ocean frontal dynamics and the development of submesoscale eddies have been difficult to observe comprehensively. Indeed, our ability to simulate submesoscale dynamics with computer models is far ahead of our ability to directly observe these processes.
The S-MODE campaign intended to (1) collect a benchmark data set with detailed measurements of the velocity and temperature field that can be used to understand how well these simulations represent the real ocean, and (2) to make measurements of the vertical velocity associated with different kinds of fine scale dynamics.
S-MODE involved measurements from ships, aircraft, and many uncrewed ocean vehicles and autonomous platforms. Many of the techniques are relatively new, and the combination of these different measurements allowed examination of submesoscale variability at a new level of detail. There was a particular focus on velocity gradients, which should allow new observations of dynamically important quantities like surface current divergence and vorticity. S-MODE had a major field campaign in April 2023 in the SWOT 1-day repeat crossover that is offshore of California.
Submesoscale fronts and eddies are believed to play an important role in vertical transport in the upper ocean, which in turn affects the air-sea exchange of heat and gasses and the availability of nutrients in the upper ocean. Over long time scales, these effects can have important implications for the evolution of Earth’s climate.
Principal investigators: Tom Farrar (WHOI), Eric D’Asaro (University of Washington).
Contact point for the study site: Tom Farrar (jfarrar@whoi.edu)