Climate of the Past Discussions www.clim-past-discuss.net 1814-9340 1814-9359 6 5 2010 10.5194/cpd-6-1589-2010 http://www.clim-past-discuss.net/6/1589/2010/ http://www.clim-past-discuss.net/6/1589/2010/cpd-6-1589-2010.html http://www.clim-past-discuss.net/6/1589/2010/cpd-6-1589-2010.pdf 1589 1628 2010-09-01 Oceanic tracer and proxy time scales revisited C. Siberlin C. Wunsch cwunsch@mit.edu Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA Quantifying time-responses of the ocean to passive and active tracers is critical for the interpretation of paleodata from sediment cores because surface-injected tracers do not instantaneously spread throughout the ocean. To obtain insights into the time response, a computationally efficient state transition matrix method is demonstrated and used to compute successive states of passive tracer concentrations in the global ocean. 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