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Fullmer, J. W. A.

Publications and source records attributed to Fullmer, J. W. A..

2 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

The baroclinic instability of highly structured one-dimensional basic states

A frictionless, adiabatic, quasi-geostrophic model on a beta-plane was employed to examine the baroclinic instability of highly structured one-dimensional basic states. Definitions of the model eigenvalue equation, the boundary conditions, and the fluxes and energetics are provided, and highly structured average wind speed and temperature profiles were selected to represent a wide range of latitudes. Attention was given to the instability source, wavelength, growth rate, phase velocity, steering levels, and the vertical structure of their amplitude, phase, meridional entropy transport, and conversion of potential-to-kinetic energy. Green modes, Charney-Eady modes, and the modes defined in the paper are examined in connection with the highly structured profiles. The eigenvalue approach is shown to be superior to the numerical time integration approach and necessary conditions for instabilities are defined.

Fullmer, J. W. A.↗
NASA NTRS1982

Calculations of the quasi-geostrophic potential vorticity gradient from climatological data

Climatological data (5-year sets) are used in calculating the quasi-geostrophic potential vorticity meridional gradient between 10 and 1000 mb for latitudes from 25 to 65 deg N in the months of January, April, July, and October. The data comprise zonal and one-month averaged values of the zonal velocity and temperature and represent seasonal transitions and extremes. It is noted that previous papers have shown that zeros of the meridional gradient are important in determining the stability properties of the atmosphere. It is shown that the profiles of the meridional gradient generated from the climatological data possess zero in all seasons and at many latitudes and levels. In all seasons, therefore, the atmosphere is shown to have a wide variety of potential sources of baroclinic instability.

Fullmer, J. W. A.↗