Accession Number : ADA312186

Title :   Hurricane Motion on a Beta Plane in an Asymmetric Balance.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Nicklas, Christopher T.

PDF Url : ADA312186

Report Date : 31 MAY 1996

Pagination or Media Count : 89

Abstract : This thesis extends asymmetric balance theory (AB) to the shallow water beta plane (Beta-AB). The physical problem studied is that of vortex motion on a beta plane in the absence of environmental steering flow. To reduce the problem to its essential physics, the mathematical formulation developed is restricted to purely linear dynamics. The linear dynamics precludes wave-wave and wave-mean-flow interactions. Vortices placed in the Beta-AB model correctly develop the wavenumber one asymmetries (the 'beta' gyres) necessary for vortex self-advection. The vortices move in a northwest direction consistent with their relative strengths. Finite drift speeds are reached in all cases. Both the Beta-AB model and a linear barotropic nondivergent model are used to investigate the existence of a translating normal mode of zero frequency. If such a mode exists, the beta gyres would be expected to remain unchanged in the absence of beta forcing. When the beta forcing is discontinued, the beta gyres axisymmetrize in both models, refuting the normal mode hypothesis.

Descriptors :   *HURRICANES, PRESSURE GRADIENTS, MATHEMATICAL MODELS, LINEAR SYSTEMS, THESES, VORTICES, COMPUTATIONAL FLUID DYNAMICS, WEATHER FORECASTING, FLOW FIELDS, TEMPERATURE GRADIENTS, PARTIAL DIFFERENTIAL EQUATIONS, WIND VELOCITY, BAROMETRIC PRESSURE, MOMENTUM, FORMULAS(MATHEMATICS), CONVECTION(ATMOSPHERIC), GEOPOTENTIAL, ROSSBY WAVES.

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE