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Xavier Carton

, the advection of surface temperature is two-dimensional, but the relation between streamfunction and temperature is a 1/ r Green’s function (as in 3D QG theory). With such properties, the SQG model has also been used to study the statistical properties of developed turbulence and of turbulent dispersion ( Held et al. 1995 ; Constantin et al. 1999 ; Hakim et al. 2002 ; Sukhatme and Pierrehumbert 2002 ; Tran and Bowman 2003 ; Scott 2006 ). In surface quasigeostrophic turbulence, vortices form

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Miguel Canals, Geno Pawlak, and Parker MacCready

1. Introduction Horizontal flow separation is common in the coastal ocean. Oscillatory as well as quasi-steady currents flow along rough topography and may lead to separation-induced eddies, which play a major role in coastal dynamics. These vortices can sometimes create spectacular patterns as they chaotically advect a tracer field. More importantly, they lead to stirring of nutrients, biogenic material ( Rankin et al. 1994 ), and pollutants ( Wolanski et al. 1984 ; Chen et al. 2005

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Daniel Hodyss and David S. Nolan

, from a Hamiltonian principle, finite-amplitude, local wave-activity conservation laws for a two-dimensional version of the anelastic equations of Lipps and Hemler (1982) . The use of the anelastic equations to study the dynamics of strong atmospheric vortices, like tropical cyclones, has been hindered by the radial dependencies in the vortex. Other meteorological problems have similar issues. Wave dynamics in large-scale flows at midlatitudes is an example of a phenomenon for which the anelastic

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Roberto Iacono

1. Introduction The stability of oceanic vortices over isolated topography has been investigated by Nycander and LaCasce (2004 , hereafter NL04) in the context of the two-dimensional (2D) inviscid Euler equation in a nonrotating environment. The main result of NL04 is that there is a large class of stable, stationary anticyclonic vortices attached to seamounts (quite wider than that found in the classical investigation by Carnevale and Frederiksen 1987 ), whereas stable cyclones can only

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M. V. Rudko, I. V. Kamenkovich, and D. S. Nolan

1. Introduction Mesoscale coherent vortices are found in every part of the World Ocean ( Jochum and Malanotte-Rizzoli 2003 ; Chelton et al. 2011 ). Observational records suggest that such vortices have a baroclinic structure, and many exhibit a very long life cycle ( Olson 1991 ). However, some of these vortices have been found to break down shortly after generation ( Schonten et al. 2000 ). Under the influence of Earth’s rotation, these structures propagate in the northwest or southwest

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Timour Radko and Cassandra Sisti

et al. 2010 ) have implicated lateral intrusions driven by double-diffusive mixing ( Stern 1967 ) in the ultimate disintegration of coherent intrathermocline vortices. Although this suggestion is plausible, observational limitations generally preclude the unambiguous confirmation of the proposed link between eddy dispersion and thermohaline interleaving. Equally challenging is the quantification of the associated mixing characteristics on the basis of field measurements, motivating a numerical

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D. C. Lewellen and W. S. Lewellen

considered. Buoyancy is not included nor is the possibility for added intensification due to subsidence warming in the tornado core. Intensification is considered only relative to conditions in the core flow aloft; that is, no attempt is made to connect that to a thermodynamic speed limit (or, more accurately, a thermodynamic velocity scale). We also concentrate on the intensification of the primary vortex; we do not consider here the added intensification that can occur in secondary vortices as

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Xinyuan Feng, Changhai Liu, Roy Rasmussen, and Guangzhou Fan

the western plateau ( Wang et al. 2009 ). The plateau vortex can occasionally trigger and interact with another unique meso-α-scale system, the southwest vortex, a name given by Chinese meteorologists to the shallow low-level cyclonic vortices (usually most notable at 700 hPa) originating over the eastern and southeastern flanks of the Tibetan Plateau in southwest China ( Luo 1992 ; Chen et al. 2007 ). For instance, the initiation of the southwest vortex has been observed in association with a

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Daniel M. Mitchell, Andrew J. Charlton-Perez, and Lesley J. Gray

1. Introduction The winter stratosphere is dominated by a strong cyclonic vortex located in both the Northern Hemisphere (NH) and Southern Hemisphere (SH). Because of the abundance of landmass in the NH compared with the SH, more planetary waves are generated and the NH vortex is more variable than that of the SH (e.g., McIntyre and Palmer 1983 ). The edge of the vortices is defined by strong potential vorticity (PV) gradients that inhibit isentropic transport through the mechanism of “Rossby

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Benjamin J. Harvey, Maarten H. P. Ambaum, and Xavier J. Carton

model include the evolution of tropopause undulations ( Juckes 1994 ; Juckes 1995 ; Muraki and Snyder 2007 ) and near-surface oceanic vortices ( Lapeyre and Klein 2006 ). This type of dynamics has also been studied by Blumen (1978) under the name of uniform potential vorticity flow. Carton (2009 , hereafter C09) provides a numerical study of smooth shielded vortices in the SQG model and compares the evolutions with those of unstable vortices under the more familiar two-dimensional Euler

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