Topographic influence on submesoscale dynamics in the Southern Ocean

• Published in: Geophysical Research Letters
• Main Authors: Rosso, Isabella, Hogg, Andrew, Kiss, Andrew E., Gayen, Bishakhdatta
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union
• Subjects: Keywords: Kinetic energy; Kinetics; Numerical models; Strain rate; Topography; Velocity; Coarser resolution model; High resolution; Mesoscale; Southern ocean; Spatial in-homogeneity; Topographic features; Topography controls; Vertical velocity; Oceanography high resolution; numerical model; Southern Ocean; Indian
• Online Access: http://hdl.handle.net/1885/102574; https://doi.org/10.1002/2014GL062720; https://openresearch-repository.anu.edu.au/bitstream/1885/102574/5/01_Rosso_Topographic_influence_on_2015.pdf.jpg

Topography influences the circulation in the Southern Ocean, generating stationary meanders in the lee of topographic features, triggering hot spots of mesoscale eddy kinetic energy, and modifying jets and fronts. However, the relationship between topography and submesoscale flows (with length scales of order 1-10 km) has not yet been explored. The first submesoscale-resolving (1/80 resolution) ocean model, with realistic topography of the Indian sector of the Southern Ocean, is used to investigate this interaction. The results show spatial inhomogeneity in submesoscale activity that is correlated with topography. Topographic influence is primarily indirect: topography controls mesoscale flows, which in turn generate submesoscale activity. Mesoscale eddy kinetic energy and strain rate can be used, to first order, to infer submesoscale vertical velocity, implying a possible route to parameterise submesoscale activity in coarser resolution models.