Lilly, D. K., 1965: On the computational stability of numerical solutions of time-dependent
non-linear geophysical fluid dynamics problems. Monthly Weather Review, 93 (1), 11-26.
Abstract: The satisfactory numerical solution of the equations of fluid dynamics
applicable to atmospheric and oceanic problems characteristically requires
a high degree of computational stability and accurate conservation of certain
statistical moments. Methods for satisfying these requirements are described
for various systems of equations typical of low Mach number fluid dynamics
systems, and are investigated in detail as applied to the two-dimensional,
inertial-plane equation for conservation of vorticity in a frictionless
non-divergent fluid.
The conservation and stability properties of the spatial differencing methods
devised by A. Arakawa are investigated by means of spectral analysis of
the stream function into finite Fourier modes. Any of two classes of linear
and quadratic conserving schemes are shown to eliminate the non-linear instability
discussed by Phillips, although the "aliasing" error remains. Stability
related to the time derivative term is investigated through analytic and
numerical solutions of a limited-component system of finite spectral equations,
equivalent to one of the quadratic conserving difference schemes, and a
number of first and second order representations of the time derivative
term are tested separately. The commonly used midpoint rule ("leapfrog")
method is shown to be unstable in some cases. Of the stable methods, that
devised by Miyakoda and the second order Adams-Bashforth method exhibit
satisfactory accuracy, while those due to Matsuno, and Lax and Wendroff
are much less accurate.
A systematic derivation of the Arakawa difference schemes is contained in
an appendix, which shows their unique satisfaction of certain prescribed
accuracy and conservation properties.