Climate of the Past Discussions www.clim-past-discuss.net 1814-9340 1814-9359 5 2 2009 10.5194/cpd-5-1231-2009 http://www.clim-past-discuss.net/5/1231/2009/ http://www.clim-past-discuss.net/5/1231/2009/cpd-5-1231-2009.html http://www.clim-past-discuss.net/5/1231/2009/cpd-5-1231-2009.pdf 1231 1258 2009-04-23 The importance of Northern Peatlands in global carbon systems during the Holocene Y. Wang yi.wang@pnl.gov N. T. Roulet S. Frolking L. A. Mysak Department of Geography and McGill School of Environment, McGill University, 3534 University, Montreal, Quebec H3A 2A7, Canada Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824, USA Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, Quebec H3A 2K6, Canada now at: Pacific Northwest National Laboratory, 999 Battelle BLVD, P.O. Box 999, MSIN K9-24, Richland, WA 99354, USA We applied an inverse model to simulate global carbon (C) cycle dynamics during the Holocene period using atmospheric carbon dioxide (CO₂) concentrations reconstructed from Antarctic ice cores and prescribed C accumulation rates of Northern Peatlands (NP) as inputs. Previous studies indicated that different sources could contribute to the 20 parts per million by volume (ppmv) atmospheric CO₂ increase over the past 8000 years. These sources of C include terrestrial release of 40–200 petagram C (PgC, 1 petagram=10¹⁵ gram), deep oceanic adjustment to a 500 PgC terrestrial biomass buildup early in this interglacial period, and anthropogenic land-use and land-cover changes of unknown magnitudes. Our study shows that the prescribed peatland C accumulation significantly modifies our previous understanding of Holocene C cycle dynamics. 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