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14C in the Deep Water of the East Atlantic

Published online by Cambridge University Press:  18 July 2016

Reiner Schlitzer
Reiner Schlitzer*
Affiliation:
Institut für Umweltphysik, Universität Heidelberg Im Neuenheimer Feld 366, D-6900 Heidelberg, FRG
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Abstract

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The renewal of east Atlantic deep water and its large-scale circulation and mixing have been studied in observed distributions of temperature, silicate, ΣCO2, and 14C. 14C variations in northeast Atlantic deep water below 3500m depth are small. Δ14C values range from − 100‰ to −125‰. 14C bottom water concentrations decrease from Δ14C =−117‰ in the Sierra Leone Basin to Δ14C = − 123‰ in the Iberian Basin and are consistent with a mean northward bottom water flow. The characteristic of the water that flows from the west Atlantic through the Romanche Trench into the east Atlantic was determined by inspection of θ/Δ14C and θ/SiO2 diagrams. A mean potential temperature of θ = 1.50 ± .05°C was found for the inflowing water. A multi-box model including circulation, mixing, and chemical source terms in the deep water has been formulated. Linear programing and least-squares techniques have been used to obtain the transport and source parameters of the model from the observed tracer fields. Model calculations reveal an inflow through the Romanche Trench from the west Atlantic, which predominates over any other inflow, of (5 ± 2) Sv (potential temperature 1.50°C), a convective turnover of (150 ± 50) years and a vertical apparent diffusivity of (4 ± 1) cm2/s. Chemical source terms are in the expected ranges.

Type
III. The Carbon Cycle
Information
Radiocarbon , Volume 28 , Issue 2A , 1986 , pp. 391 - 396
Copyright
Copyright © The American Journal of Science 

References

Broecker, W S, 1979, A revised estimate for the radiocarbon age of North Atlantic Deep Water: Jour Geophys Research, v 84, p 3218–3226.Google Scholar
Levitus, S, 1982, Climatological atlas of the world ocean: NOAA prof paper 13, Rockville, Maryland.Google Scholar
Schlitzer, R, Roether, W, Weidmann, U, Kalt, P and Loosli, H, 1985, A meridional 14C- and 39Ar-section in North East Atlantic Deep Water: Tour Geophys Research, v 90 p 6945–6952.Google Scholar
Stuiver, M, 1976, The 14C distribution in west Atlantic abyssal waters: Earth Planetary Sci Letters, v 32, p 322–330.Google Scholar
Stuiver, M, Quay, P D and Östlund, H G, 1983, Abyssal water carbon-14 distribution and the age of the world oceans: Science, v 219, p 849–851.Google Scholar
Vangriesheim, A, 1980, Antarctic bottom water flow through the Vema fracture zone: Oceanol acta, v 3, p 199–207.Google Scholar
Wüst, G, 1936, Das Bodenwasser und die Gliederung der Atlantischen Tiefsee, in Defant, A, ed, Wiss Ergebn, Dt Atlant Exp “Meteor” 1925–1927: v VI/I, p 3–106.Google Scholar