year getting longer

The anthropogenic increase in greenhouse gas concentrations in the Earth atmosphere will probably induce important modifications of the global circulation in the atmosphere and ocean. Due to the angular momentum conservation of the Earth-atmosphere-ocean system, variation of length-of-day(LOD) can be expected.

By using the outputs of models participating to the Coupled Model Intercomparison Project (CMIP-2) we reach the following conclusions: (1) the models globally agree to an increase of the LOD of the order of 1 microsecond/year (2) the effect is mostly associated with an increase of the mean zonal wind, of which about one third is compensated by a change in mass repartition.
Olivier de Viron and others, Geophysical Research Letters, Vol 29, Issue 7, pages 50-1-50-4 April 2002

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