Hide, R., J. Dickey, S. Marcus, R. Rosen and D. Salstein, 1995: Atmospheric angular momentum fluctuations in general circulation models during the AMIP period (Diagnostic Subproject 15). Abstracts of the First International AMIP Scientific Conference, Monterey, California, 85.

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Irregular fluctuations in all three components of the Earth's rotation vector on sub-decadal time scales are excited by compensating fluctuations in the total angular momentum of the atmosphere, through stresses exerted by the atmosphere on the underlying planet in the oceanic and continental boundary layers, and also over topography, (including the equatorial bulge). Their determinations by geodesists and astronomers serve as a useful surrogate data set for atmospheric angular momentum (AAM) fluctuations, which are intimately linked with global-scale energy fluctuations and must be simulated correctly in any successful global numerical model. In Diagnostic Sub-Project 15 (Atmospheric Angular Momentum) we have intercompared the AMIP models on the basis of their ability to represent the observed seasonal and interannual AAM fluctuations and certain well-established regional phenomena discovered in recent AAM studies. We have also investigated regional contributions to the discrepancies between models revealed by the intercomparisons. When AMIP "history data" become available, these studies will be extended to shorter (intra-seasonal) time scales, where pronounced AAM fluctuations are also known to occur. Detailed accounts of our findings to date are in preparation for submission to various journals.