Kvaleberg, E. (2004). Generation of Cold Core Filaments and Eddies Through Baroclinic Instability on a Continental Shelf . Ph.D. thesis, Florida State University, Tallahassee, FL.
Abstract: The formation of cold core filaments on an idealized continental shelf is investigated using a numerical model to simulate the ocean's response to surface cooling. A horizontal density gradient forms because of uneven buoyancy loss due to the sloping bottom, and this gradient induces an alongshelf current in thermal wind balance, that in time becomes unstable. As the instabilities grow, filaments, and later eddies, are generated so that dense water near the coast is mixed offshore. Scaling arguments of the filament wavelength indicate that the current is baroclinically unstable, and an analytical model of the frontal expansion with time is in very good agreement with the simulations. This study was inspired by satellite observations of sea surface temperature on the West Florida Shelf during the winter months, in which it is clearly seen that cold core filaments extend from a thermal front. Numerical experiments are therefore designed to allow for reliable comparisons with conditions in this region.
Kvaleberg, E., Morey, S. L., & O'Brien, J. J. (2004). (J. Cote, Ed.). Research Activities in Atmospheric and Ocean Modeling, Report No. 34. Geneva, Switzerland: World Meteorological Organization.
Kvaleberg, E., Morey, S. L., & O'Brien, J. J. Modeling frontal instabilities in the Gulf of Mexico (J. Cote, Ed.). Research Activities in Atmospheric and Ocean Modeling, Report No. 33. Geneva, Switzerland: World Meteorological Organization.
Kvaleberg, E., Morey, S. L., & O'Brien, J. J. (2003). Frontogenesis and subsequent formation of cold filaments and eddies on an idealized shelf. In OCEANS 2003 MTS/IEEE: Celebrating the Past... Teaming toward the Future (pp. 2831–2834).
LaCasce, J. H., Escartin, J., Chassignet, E. P., & Xu, X. (2018). Jet instability over smooth, corrugated and realistic bathymetry. J. Phys. Oceanogr. , .
Abstract: The stability of a horizontally- and vertically-sheared surface jet is examined, with a focus on the vertical structure of the resultant eddies. Over a flat bottom, the instability is mixed baroclinic/barotropic, producing strong eddies at depth which are characteristically shifted downstream relative to the surface eddies. Baroclinic instability is suppressed over a large slope for retrograde jets (with a flow anti-parallel to topographic wave propagation), and to a lesser extent for prograde jets (with flow parallel to topographic wave propagation), as seen previously. In such cases, barotropic (lateral) instability dominates if the jet is sufficiently narrow. This yields surface eddies whose size is independent of the slope but proportional to the jet width. Deep eddies still form, forced by interfacial motion associated with the surface eddies, but they are weaker than under baroclinic instability and are vertically aligned with the surface eddies. A sinusoidal ridge acts similarly, suppressing baroclinic instability and favoring lateral instability in the upper layer.
A ridge with a 1 km wavelength and an amplitude of roughly 10 m is sufficient to suppress baroclinic instability. Surveys of bottom roughness from bathymetry acquired with shipboard multibeam echosounding reveal that such heights are common, beneath the Kuroshio, the Antarctic Circumpolar Current and, to a lesser extent, the Gulf Stream. Consistent with this, vorticity and velocity cross sections from a 1/50° HYCOM simulation suggest that Gulf Stream eddies are vertically aligned, as in the linear stability calculations with strong topography. Thus lateral instability may be more common than previously thought, due to topography hindering vertical energy transfer.
Lagerloef, G. S. E., Lukas, R., Bonjean, F., Gunn, J. T., Mitchum, G. T., Bourassa, M., et al. (2003). El Niño Tropical Pacific Ocean surface current and temperature evolution in 2002 and outlook for early 2003. Geophys. Res. Lett. , 30 (10).
Langland, R. H., Maue, R. N., & Bishop, C. H. (2008). Uncertainty in atmospheric temperature analyses. Tellus A , 60 (4), 598–603.
LaRow, T. E., Y.-K. Lim, D. W. Shin, S. D. Cocke, and E. Chassignet. (2007). High resolution ensemble west Atlantic basin seasonal hurricane simulations . CAS/JSC Working Group on Numerical Experimentation.
LaRow, T. E., & Cocke, S. (2004, Spring). Methods for Multi¬Model Proxies for Climate Studies. CLIVAR Exchanges Newsletter .
LaRow, T. E., & Cocke, S. D. (1999). Simulation of the 1997/98 and 1991/92 ENSO event using a Coupled Ocean-Atmosphere Regional Spectral Model (H. Ritchie, Ed.). Research Activities in Atmospheric and Oceanic Modelling.