Test Case 6 - Rossby-Haurwitz Wave
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Experiment 6 tests the full equations with semi-implicit time stepping.
For this experiment horizontal diffusion has been enabled.
The kinetic and potential
energy spectra are plotted, and the conservation properties computed.
Error analysis has been disabled.
Contour plots of the height have been enabled on a cylindrical projection,
with the center of the viewpoint on the international dateline.

