A new study by researchers at UNSW’s Coastal and Regional Oceanography Lab has shown that ocean currents in different hemispheres are surprisingly similar. The study, published in Geophysical Research Letters, has been selected as an Editors’ Highlight in the American Geophysical Union’s Earth and Space Science News.
The project, led by Dr Matt Archer, analyzed more than a decade of observations gathered by teams working in Sydney, Australia and Miami, USA. The international collaboration used high-frequency radar systems to study surface velocities in two western boundary current systems: the East Australian Current, which flows southward along the coast of New South Wales, and the Florida Current, which flows northward along the east coast of Florida into the Atlantic Ocean.
Western boundary currents are swift-flowing, warm currents that form in every ocean basin, and are important for transporting heat and water from the tropics to higher latitudes. However, they are highly variable with a significant meandering flow, which makes it difficult to compare data from different geographical locations.
Archer and colleagues were able to compensate for this meandering motion by transforming the data to a “jet-centered” coordinate frame that allowed them to compare the two currents. Their results revealed that the East Australian Current and the Florida Current are remarkably similar, despite contrasting coastlines, wind forcing, and air-sea interactions.
“These results provide a new view of western boundary currents and will be helpful for evaluating higher resolution numerical models to better understand mechanisms of variability in western boundary currents”, said Dr Jane Sprintall, editor of Geophysical Research Letters.
Matt carried out the research at UNSW Sydney under the supervision of Moninya Roughan and Shane Keating. He will take up a new position as a postdoctoral researcher at NASA’s Jet Propulsion Laboratory later this year.
Citation: Archer, M. R., Keating, S. R., Roughan, M., Johns, W. E., Lumpkin, R., Beron‐Vera, F. J., & Shay, L. K. . The kinematic similarity of two western boundary currents revealed by sustained high‐resolution observations. Geophysical Research Letters, 45. https://doi.org/10.1029/2018GL078429