In a stratified rotating fluid, frictionally driven circulations couple with the buoyancy field over sloping topography. Analytical and numerical methods are used to quantify the impact of this coupling on the vertical circulation, spindown of geostrophic flows, and the formation of a shelfbreak jet. Over a stratified. slope, linear spindown of a geostrophic along-isobath flow induces cross-iso...

Idealized experiments using linear (LM) and nonlinear (NM) multilevel global spectral models have been carried out to investigate and understand the impact of nonlinearities on the stationary wave response in the tropical atmosphere and its sensitivity to the vertical profile of heating. It is found that nonlinearities exert a dominant influence on the low-latitude stationary Kelvin and Rossby ...

A Poisson regression between the observed climatology of tropical cyclogenesis (TCG) and largescale climate variables is used to construct a TCG index. The regression methodology is objective and provides a framework for the selection of the climate variables in the index. Broadly following earlier work, four climate variables appear in the index: low-level absolute vorticity, relative humidity...

The formation of orographic wakes and vortices is studied within the context of numerically simulated viscous flow with uniform basic-state wind and stability past elongated free-slip ridges. The viscosity and thermal diffusivity are sufficiently large that the onset of small-scale turbulence is suppressed. It is found in Part I of this study that wake formation in the viscous flow is closely t...

dehbid mylonite nappes associated with the tutak gneiss dome as the zagros hinterland involved-basement window in the zagros orogenic belt has significant components of dextral sense of shear along the mylonite nappes and are related to the high proportion of simple shear relative to pure shear deformation. kinematic vorticity analysis (wk) was made in order to determination of relative amounts...

A nonhydrostatic cloud model is used to examine the thermomechanics of tropical cyclogenesis under realistic meteorological conditions. Observations motivate the focus on the problem of how a midtropospheric cyclonic vortex, a frequent by-product of mesoscale convective systems during summertime conditions over tropical oceans, may be transformed into a surface-concentrated (warm core) tropical...

The persistence of the North Atlantic Oscillation (NAO) is studied using observations of the threedimensional vorticity budget in the Atlantic sector. Analysis of the relative vorticity tendency equation shows that convergence of eddy vorticity flux in the upper troposphere counteracts the effect of anomalous largescale divergence at the upper level. At low levels, the convergence associated wi...

The single-mode equations of Boussinesq thermal convection have been modified to include the vertical component of vorticity, which has led, in certain parameter ranges, to a new family of solutions for stationary convection in the absence of external constraints. The features of these solutions are discussed and a comparison with the family of solutions possessing zero vertical vorticity, whic...