Assessing eddy parameterization schemes in a differentially heated rotating annulus experiment

Journal article

We investigate three of the most common hypotheses underpinning parameterizations of baroclinic eddy fluxes in the context of the differentially heated rotating annulus experiment. The investigation is carried out over a region of parameter space which embraces the onset of baroclinic instability, the regular wave regime and the onset of irregular flows, the latter of which is arguably most relevant to oceanic conditions. Through diagnostics from a 2D axisymmetric and a 3D eddy-resolving numerical model, it was found that the transport of heat by baroclinic eddies is not strictly an adiabatic process but that diffusive 'ventilation' of the flow in the thermal boundary layers is significant during the nonlinear development of the flow. Total heat transport, however, is conserved overall. Depending on the stages of flow evolution and on the region in parameter space under consideration, either heat, quasi-geostrophic potential vorticity (QGPV) or relative vorticity (QGRV) may become a suitable variable on which to parameterize baroclinic eddy fluxes in a down-gradient manner. These results raise issues for eddy parameterization schemes that rely on these assumptions in ocean and atmosphere models. © 2009 Elsevier Ltd.

Authors: Perez-Perez, E; Read, P; Moroz, I

• Publication status: Published
• Journal: OCEAN MODELLING
• Volume: 32
• Issue: 3-4
• Pages: 118-131
• Publication date: 2010-01-01
• DOI: 10.1016/j.ocemod.2009.11.003
• ISSN: 1463-5003
• Language: English
• Keywords: Heat transfer; Laboratory experiment; Baroclinic instability; Potential vorticity; Eddy parameterization