Climate of the Past Discussions www.clim-past-discuss.net 1814-9340 1814-9359 5 3 2009 10.5194/cpd-5-1297-2009 http://www.clim-past-discuss.net/5/1297/2009/ http://www.clim-past-discuss.net/5/1297/2009/cpd-5-1297-2009.html http://www.clim-past-discuss.net/5/1297/2009/cpd-5-1297-2009.pdf 1297 1336 2009-05-05 Warm Paleocene/Eocene climate as simulated in ECHAM5/MPI-OM M. Heinemann malte.heinemann@zmaw.de J. H. Jungclaus J. Marotzke Max Planck Institute for Meteorology (MPI-M), Hamburg, Germany International Max Planck Research School on Earth System Modelling (IMPRS-ESM), Hamburg, Germany We investigate the late Paleocene/early Eocene (PE) climate using the coupled atmosphere-ocean-sea ice model ECHAM5/MPI-OM. The surface in our PE control simulation is on average 297 K warm and ice-free, despite a moderate CO₂ concentration of 560 ppm. Compared to a pre-industrial reference simulation (PR), low latitudes are 5 to 8 K warmer, while high latitudes are up to 40 K warmer. 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