Journal ArticleDOI
Production and accumulation of calcium carbonate in the ocean: Budget of a nonsteady state
TLDR
In this article, it was shown that the oceans are not presently in a steady state, suggesting that outputs have been overestimated or inputs underestimated, that one or more other inputs have not been identified, and/or that one of the missing calcium sources might be groundwater, although its presentday input is probably much smaller than that of rivers.Abstract:
Present-day production of CaCO3 in tne world ocean is calculated to be about 5 billion tons (bt) per year, of which about 3 bt accumulate in sediments; the other 40% is dissolved. Nearly half of the carbonate sediment accumulates on reefs, banks, and tropical shelves, and consists largely of metastable aragonite and magnesian calcite. Deep-sea carbonates, predominantly calcitic coccoliths and planktonic foraminifera, have orders of magnitude lower productivity and accumulation rates than shallow-water carbonates, but they cover orders of magnitude larger basin area. Twice as much calcium is removed from the oceans by present-day carbonate accumulation as is estimated to be brought in by rivers and hydrothermal activity (1.6 bt), suggesting that outputs have been overestimated or inputs underestimated, that one or more other inputs have not been identified, and/or that the oceans are not presently in steady state. One “missing” calcium source might be groundwater, although its present-day input is probably much smaller than that of rivers. If, as seems likely, CaCO3 accumulation presently exceeds terrestial and hydrothermal input, this imbalance presumably is offset by decreased accumulation and increased input during lowered sea level: shallow-water accumulation decreases by an order of magnitude with a 100 m drop in sea level, while groundwater influx increases because of heightened piezometric head and the diagenesis of metastable aragonite and magnesian calcite from subaerially exposed shallow-water carbonates.read more
Citations
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Journal ArticleDOI
Estimating Particulate Inorganic Carbon Concentrations of the Global Ocean From Ocean Color Measurements Using a Reflectance Difference Approach
TL;DR: In this paper, a new algorithm for estimating particulate inorganic carbon (PIC) concentrations from ocean color measurements is presented, which is more resistant to atmospheric correction errors and residual errors in sun glint corrections, as seen by a reduction in the speckling and patchiness in the satellite derived PIC images.
Book ChapterDOI
Contribution of Calcareous Plankton Groups to the Carbonate Budget of South Atlantic Surface Sediments
Karl-Heinz Baumann,Babette Böckel,Barbara Donner,Sabine Gerhardt,Rüdiger Henrich,Annemiek Vink,Andrea N A Volbers,Helmut Willems,Karin A F Zonneveld +8 more
TL;DR: A total of more than 400 surface sediment samples from the equatorial, central and subpolar South Atlantic Ocean were investigated for their carbonate content as well as for the carbonate contribution from various calcareous plankton groups as discussed by the authors.
Journal ArticleDOI
Shallow‐depth CaCO3 dissolution: Evidence from excess calcium in the South China Sea and its export to the Pacific Ocean
Zhimian Cao,Minhan Dai +1 more
TL;DR: In this paper, the authors presented the results of the South China Sea Institute of Oceanology (SCEI) and the Chinese Academy of Sciences (CAS) in 2009.
Journal ArticleDOI
Calcium isotopes in deep time: Potential and limitations
TL;DR: In this article, it was shown that carbonate δ44/40Ca values are sensitive to precipitation rates with higher rates generally leading to larger fractionation of carbonate sediments, and that relatively slow rates of recrystallization and neomorphism can lead to significant changes in bulk carbonate sediment values.
Journal ArticleDOI
Comparative carbon cycle dynamics of the present and last interglacial
Victor Brovkin,Tim Brücher,Thomas Kleinen,Sönke Zaehle,Fortunat Joos,Raphael Roth,Renato Spahni,Jochen Schmitt,Hubertus Fischer,Markus Leuenberger,Emma J. Stone,Andy Ridgwell,Jérôme Chappellaz,Jérôme Chappellaz,Natalie Kehrwald,Carlo Barbante,Thomas Blunier,Dorthe Dahl Jensen +17 more
TL;DR: In this paper, the authors identify and review twelve biogeochemical mechanisms of terrestrial (vegetation dynamics and CO2 fertilization, land use, wildfire, accumulation of peat, changes in permafrost carbon, subaerial volcanic outgassing) and marine origin (changes in sea surface temperature, carbonate compensation to deglaciation and terrestrial biosphere regrowth, shallow-water carbonate sedimentation, change in the soft tissue pump, and methane hydrates), which potentially may have contributed to the CO2 dynamics during interglacials but which remain
References
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Journal ArticleDOI
A 17,000-year glacio-eustatic sea level record: influence of glacial melting rates on the Younger Dryas event and deep-ocean circulation
TL;DR: In this paper, a global oxygen isotope record for ocean water has been calculated from the Barbados sea level curve, allowing separation of the ice volume component common to all isotope records measured in deep-sea cores.
Journal ArticleDOI
The carbonate-silicate geochemical cycle and its effect on atmospheric carbon dioxide over the past 100 million years
TL;DR: In this article, a computer model has been constructed that considers the effects on the CO/sub 2/ level of the atmosphere, and the Ca, Mg, and HCO/sub 3/ levels of the ocean, of the following processes: weathering on the continents of calcite, dolomite, and calcium-and-magnesium-containing silicates; biogenic precipitation and removal of CaCO 3/from the ocean; removal of Mg from the ocean via volcanic-seawater reaction; and the metamorphic-magmatic decarbon
Journal ArticleDOI
Vostok ice core provides 160,000-year record of atmospheric CO2
TL;DR: In this article, direct evidence of past atmospheric CO2 changes has been extended to the past 160,000 years from the Vostok ice core, showing an inherent phenomenon of change between glacial and interglacial periods.
Journal ArticleDOI
Biological communities at the Florida escarpment resemble hydrothermal vent taxa.
Charles K. Paull,Barbara Hecker,R.F. Commeau,R. P. Freeman-Lynde,C. Neumann,W.P. Corso,Stjepko Golubic,J.E. Hook,Elisabeth L. Sikes,Joseph R. Curray +9 more
TL;DR: Dense biological communities of large epifaunal taxa similar to those found along ridge crest vents at the East Pacific Rise were discovered in the abyssal Gulf of Mexico.
Journal ArticleDOI
A biogeochemical study of the coccolithophore, Emiliania huxleyi, in the North Atlantic
Patrick M. Holligan,Emilio Fernández,James Aiken,William M. Balch,Philip W. Boyd,Peter H. Burkill,Miles S. Finch,Stephen B. Groom,Gillian Malin,Kerstin Muller,Duncan A. Purdie,Carol V. Robinson,Charles C. Trees,Suzanne M. Turner,Paul van der Wal +14 more
TL;DR: The biogeochemical properties of an extensive bloom (∼250,000 km2) of the coccolithophore, Emiliania huxleyi, in the north east Atlantic Ocean were investigated in June 1991.
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