Past and Present of Sediment and Carbon Biogeochemical Cycling Models
Biogeosciences, 1, 11–32, 2004 www.biogeosciences.net/bg/1/11/ Biogeosciences SRef-ID: 1726-4189/bg/2004-1-11 Past and present of sediment and carbon biogeochemical cycling models F. T. Mackenzie1, A. Lerman2, and A. J. Andersson1 1Department of Oceanography, University of Hawaii, Honolulu, Hawaii 96822, USA 2Department of Geological Sciences, Northwestern University, Evanston, Illinois 60208, USA Received: 25 April 2004 – Published in Biogeosciences Discussions: 24 May 2004 Revised: 1 August 2004 – Accepted: 10 August 2004 – Published: 20 August 2004 Abstract. The global carbon cycle is part of the much more thermore, evidence from the inorganic carbon cycle indicates extensive sedimentary cycle that involves large masses of that deposition and net storage of CaCO3 in sediments ex- carbon in the Earth’s inner and outer spheres. Studies of ceed inflow of inorganic carbon from land and produce CO2 the carbon cycle generally followed a progression in knowl- emissions to the atmosphere. In the shallow-water coastal edge of the natural biological, then chemical, and finally ge- zone, increase in atmospheric CO2 during the last 300 years ological processes involved, culminating in a more or less of industrial time may have reduced the rate of calcification, integrated picture of the biogeochemical carbon cycle by the and continuation of this trend is an issue of serious environ- 1920s. However, knowledge of the ocean’s carbon cycle be- mental concern in the global carbon balance. havior has only within the last few decades progressed to a stage where meaningful discussion of carbon processes on an annual to millennial time scale can take place.
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