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Decadal Changes of Radiocarbon in the Surface Bay of Bengal: Three Decades After Geosecs and One Decade After WOCE

Published online by Cambridge University Press:  18 July 2016

Koushik Dutta ,
G V Ravi Prasad ,
Dinesh K Ray  and
Sanjeev Raghav
Koushik Dutta*
Affiliation:
Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005, India
G V Ravi Prasad
Affiliation:
Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005, India Center for Applied Isotope Studies, University of Georgia, Athens, Georgia 30602, USA
Dinesh K Ray
Affiliation:
Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005, India
Sanjeev Raghav
Affiliation:
Marine Wing, Geological Survey of India, Kolkata 700 091, India
*
Corresponding author. Email: kdutta@d.umn.edu
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Abstract

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Radiocarbon was measured in the surface seawater dissolved inorganic carbon (DIC) of the Bay of Bengal during November 2006. A meridional transect of the Δ14C in DIC was obtained from measurements in closely spaced samples collected roughly along 88°E. The Δ14C of these samples ranged from 44‰ to 57.7‰ (mean 51.8 ± 1.1‰, n = 12), and 38‰ at one station in the northern Bay of Bengal. The overall pattern of 14C distribution in DIC of surface Bay of Bengal during 2006 was roughly similar to that during the WOCE expedition of 1995. These results indicate a Δ14C decline rate of ∼4‰ per decade since WOCE in the surface Bay of Bengal, which is much smaller compared to a decline rate of ∼25‰ per decade observed in the 2 decades between the GEOSECS and WOCE expeditions, due to the smaller atmosphere-ocean Δ14C gradient.

Type
Marine
Information
Radiocarbon , Volume 52 , Issue 3: 20th Int. Radiocarbon Conference Proceedings , 2010 , pp. 1191 - 1196
Copyright
Copyright © 2010 by the Arizona Board of Regents on behalf of the University of Arizona 

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