Climate of the Past www.clim-past.net 1814-9324 1814-9332 2 2 2006 10.5194/cp-2-131-2006 http://www.clim-past.net/2/131/2006/ http://www.clim-past.net/2/131/2006/cp-2-131-2006.html http://www.clim-past.net/2/131/2006/cp-2-131-2006.pdf 131 136 2006-10-12 Equatorial insolation: from precession harmonics to eccentricity frequencies A. Berger M. F. Loutre J. L. Mélice Université catholique de Louvain, Institut d'Astronomie et de Géophysique G. Lemaître, 2 Chemin du Cyclotron, 1348 Louvain-la-Neuve, Belgium Institut de Recherche pour le Développement, Department of Oceanography, University of Cape Town, Rondebosch 7701, South Africa Since the paper by Hays et al. (1976), spectral analyses of climate proxy records provide substantial evidence that a fraction of the climatic variance is driven by insolation changes in the frequency ranges of obliquity and precession variations. 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