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We compare the tropicaloscillations and planetary scale Kelvin waves in four troposphere-stratosphereclimate models and the assimilated dataset produced by the United KingdomMeteorological Office (UKMO). The comparison has been made in the GRIPSframework "GCM-Reality Intercomparison Project for SPARC", where SPARCis Stratospheric Processes and their Role in Climate, a project of the WorldClimate Research Program. The four models evaluated are European members ofGRIPS: the UKMO Unified Model (UM), the model of the Free University in Berlin (FUB–GCM),the ARPEGE-climat model of the French National Centre for MeteorologicalResearch (CNRM), and the Extended UGAMP GCM (EUGCM) of the Centre for GlobalAtmospheric Modelling (CGAM). The integrations were performed with different,but annually periodic external conditions (e.g., sea-surface temperature, seaice, and incoming solar radiation). The structure of the tropical winds and thestrengths of the Kelvin waves are examined. In the analyses where the SAO(Semi-Annual Oscillation) and the QBO (Quasi-Biennal Oscillation) are reasonablywell captured, the amplitude of these analysed Kelvin waves is close to thatobserved in independent data from UARS (Upper Atmosphere Research Satellite). Inagreement with observations, the Kelvin waves generated in the models propagateinto the middle atmosphere as wave packets, consistent with a convective forcingorigin. In three of the models, slow Kelvin waves propagate too high and theiramplitudes are overestimated in the upper stratosphere and in the mesosphere,the exception is the UM which has weaker waves. None of the modelled waves aresufficient to force realistic eastward phases of the QBO or SAO. Although theSAO is represented by all models, only two of them are able to generatewesterlies between 10 hPa and 50 hPa. The importance of the role played in theSAO by unresolved gravity waves is emphasized. Although it exhibits someunrealistic features, the EUGCM, which includes a parametrization of gravitywaves with a non-zero phase speed, is able to simulate clear easterly towesterly transitions as well as westerlies with down-ward propagation. Thermaldamping is also important for the westerly forcing in the stratosphere.  <b>Key words. </b>Meteorology and atmospheric dynamics (middleatmosphere dynamics; tropical meterology; waves and tides

The SAO and Kelvin waves in the EuroGRIPS GCMS and the UK Met. Office analyses