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Showing 1 to 18 of 18 for “"geostrophic balance"”.
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Instability Waves in the Gulf Stream Front and Its Thermocline Layer
… shoreward of the front. The basic state is geostrophic balance and constant potential vorticity in the two active layers, but the perturbations are ageostrophic. The flow is found to be unstable to long wave perturbations, the wavelength of the most unstable wave to be of order 10 radii of …
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The Southern Ocean meridional overturning circulation as diagnosed from an eddy permitting state estimate
… forcing overcomes eddy and wind forcing to balance a poleward geostrophic transport and allows the buoyancy budget to be closed. Pressure forcing is also lowest order at depth. Indeed, the Southern Ocean’s characteristic multiple cell overturning is primarily in geostrophic balance. Several …
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The southern ocean meridional overturning circulation as diagnosed from an eddy permitting state estimate
… forcing overcomes eddy and wind forcing to balance a poleward geostrophic transport and allows the buoyancy budget to be closed. Pressure forcing is also lowest order at depth. Indeed, the Southern Ocean's characteristic multiple cell overturning is primarily in geostrophic balance. Several …
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Cross-shelf circulation and momentum and heat balances over the inner continental shelf near Martha's Vineyard, Massachusetts
… The subtidal, depth-average cross-shelf momentum balance is a combination of geostrophic balance and a coastal set-up and set-down balance driven by the cross-shelf wind stress. The estimated wave radiation stress gradient is also large. The dominant along-shelf momentum balance is between the …
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Cross-shelf circulation and momentum and heat balances over the inner continental shelf near Martha's Vineyard, Massachusetts
… The subtidal, depth-average cross-shelf momentum balance is a combination of geostrophic balance and a coastal set-up and set-down balance driven by the cross-shelf wind stress. The estimated wave radiation stress gradient is also large. The dominant along-shelf momentum balance is between the …
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The Impact of Stratified Ambient Water On Freshwater Transport In A River Plume
… Reconstructed alongshore velocities based on geostrophic balance prove that the different distributions of isopycnals cause differences in alongshore velocity fields. Higher salinity anomaly inflows form surface advected plumes which perform similarly to non-stratified cases, without eddy …
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Inner Shelf Circulation off Cartagena De Indias, Caribbean Coast of Colombia
… most of the year and the flow is found to be in geostrophic balance. In addition to the subtidal flows, a strong diurnal (24 hour) oscillatory signal is present in the alongshore current flow. The observed diurnal flows are found to be driven by the diurnal wind forcing (sea breeze) that is …
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Vertical transport at curved ocean fronts
… to be directed parallel to the front and in geostrophic balance, with the Coriolis force balancing the cross-front pressure gradient. Since geostrophic flow is horizontally nondivergent, vertical motion relies on the ageostrophic component of the flow. Current theories of frontal vertical …
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Magnetic Stability Analysis for the Geodynamo
… the flow to be a stationary solution of the geostrophic balance equation where buoyancy, pressure and the Coriolis forces are in equilibrium, we computed the geophysically scaled ratio of the Lorentz to the Coriolis forces and found it to be O(1) for flows with a large convective component. …
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Towards Improved Estimates of Upper Ocean Energetics
… wind work calculations. In this research, geostrophic, ageostrophic, Ekman, and total current decompositions are all used to calculate wind work. Geostrophic currents are formed by the balance of surface pressure gradients and the Coriolis effect. Ageostrophic currents, on the other hand, …
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Global omega equation: derivation and application to tropical cyclogenesis in the north Atlantic Ocean
The quasi-geostrophic omega equation has been used extensively to examine the large-scale vertical velocity patterns of atmospheric systems. It is derived from the quasi-geostrophic equations, a balanced set of equations based on the partitioning of the horizontal wind into a geostrophic and an …
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Makassar Strait Intraseasonal Variability
… non-dispersive relationship and semi-geostrophic balance. Current meters at 750 m and 1500 m further provide evidence that the vertical structure of the Kelvin waves resembles that of a second baroclinic mode. We propose that the intraseasonal Kelvin waves emanate from the tropical …
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Time-Lapse Acoustic Imaging of the Oceanic Energy Cascade
… to the horizontal, suggesting currents in geostrophic balance. Temporal variations in pycnocline depth and in reflection tilt are consistent with northeastward advection of a mesoscale anticyclonic vortex. Comparison with contemporaneous satellite measurements of sea-surface temperature and …
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Mixing and secondary circulation in Juan de Fuca Strait
… transverse currents are largest. A momentum balance using historical sea level and current meter data suggests that the vertical eddy viscosity Aᵥ ≈ 0.02 m²s⁻¹ at interfacial depths in May. The mean circulation in Juan de Fuca Strait-depths is highly seasonal in nature, however, and larger …
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Eddy forcing of the mean circulation in the western North Atlantic
… terms in the mean momentum, vorticity, and heat balances in three regions of the Western North Atlantic -- the northern recirculation, the southern recirculation, and the mid-ocean. The data from the last decade of field experiments suggest somewhat different conclusions from the earlier analysis …
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The kinematics and dynamics of the New England continental shelf and shelf/slope front
… time derivative term in the cross-shelf momentum balance is comparable with the Coriolis term while the advective terms are 2 to 10 times smaller, on the average. The semi-diurnal tide is barotropic over the shelf with current magnitudes that increase almost by a factor of two between the shelf …
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Numerical Simulation of the Dynamics of Summer Shamal Dust Storms
… (equatorward) side of the LE region. A quasi-balanced anticyclonic gyre at 500 hPa develops to the west of the AP over the Red Sea, which subsequently expands and strengthens over time responding to height rises generated above a well-heated ground by surface sensible heating subsequently …
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The evolution and breakdown of submesoscale instabilities
… will investigate the way in which symmetric and ageostrophic baroclinic instabilities interact when simultaneously present in a flow, with focus on the growth rates and energetic pathways of previously unexplored dynamic instabilities that arise in this paradigm; three-dimensional, mixed …