Mechoso95 Mechoso, C. R., 1995: Simulations of planetary waves with AGCMs (Diagnostic Subproject 16). Abstracts of the First International AMIP Scientific Conference, Monterey, California, 80.

The major objectives in the AMIP subproject on the simulations of the stratospheric circulation are 1) to determine the extent to which AGCMs can simulate the seasonal cycle in the stratosphere with emphasis on tropospheric-stratospheric connections in reference to planetary-wave behavior, and the formation and breakdown of the westerly vortex, and 2) to analyze systematic differences in the behavior of planetary waves between models according to the vertical extent and resolution. As a preliminary step towards these goals we have examined the seasonal and interannual variability of planetary waves simulated by the AGCMs participating in AMIP. The emphasis is on the extratropical troposphere of both hemispheres. The results of this study will be presented and discussed in view of the differences between vertical resolution and extent of the models.

We also present an extensible environment called CONQUEST, which can be used to extract and catalog features in very large datasets. This environment greatly facilitates the retrieval, analysis and visualization of features such as the amplitude, phase speed, and phase difference with height (indicating the direction of vertical energy propagation) produced by various models. The ability to "automatically" identify events when there is upward propagation of wave energy from the troposphere allows for an straightforward comparison of the frequency, duration and strength of such events in observational data and the AGCM output from the AMIP simulations. We expect that this comparison will help to identify systematic errors in the model simulations of the dynamics of vertically propagating Rossby waves.