The volume transport of the Antarctic Circumpolar Current (ACC) is described in textbooks as set by wind and buoyancy forcing. However, eddy-permitting numerical ocean models indicate minimal sensitivity of ACC transport to the wind stress. A new model - building on the recent GEOMETRIC parameterisation of mesoscale eddies - is developed relating ACC transport to three length scales divided by the residence time of Southern Ocean eddy energy (set by bottom drag), and independent of the wind stress. Observation-based estimates of the parameters give an ACC transport of realistic magnitude.
Co-authors: Xiaoming Zhai (University of East Anglia), James Maddison (University of Edinburgh), Julian Mak (Hong Kong University of Science and Technology)
By Matthew Juniper
By Sergey Gavrilyuk
By David Lannes
