Climate of the Past Discussions www.clim-past-discuss.net 1814-9340 1814-9359 2 6 2006 10.5194/cpd-2-1277-2006 http://www.clim-past-discuss.net/2/1277/2006/ http://www.clim-past-discuss.net/2/1277/2006/cpd-2-1277-2006.html http://www.clim-past-discuss.net/2/1277/2006/cpd-2-1277-2006.pdf 1277 1292 2006-12-12 The DO-climate events are noise induced: statistical investigation of the claimed 1470 years cycle P. D. Ditlevsen pditlev@gfy.ku.dk K. K. Andersen A. Svensson The Niels Bohr Institute, Department of Geophysics, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen O, Denmark The significance of the apparent 1470 years cycle in the recurrence of the Dansgaard-Oeschger (DO) events, observed in the Greenland ice cores, is debated. Here we present statistical significance tests of this periodicity. The detection of a periodicity relies strongly on the accuracy of the dating of the DO events. 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