Glacial-to-Holocene Redistribution of Carbonate Ion in the Deep Sea
Wallace S. Broecker,*
Elizabeth Clark
We have reconstructed the glacial-age distribution of carbonate ion
concentration in the deep waters of the equatorial ocean on the basis
of differences in weight between glacial and Holocene foraminifera
shells picked from a series of cores spanning a range of water depth on
the western Atlantic's Ceara Rise and the western Pacific's Ontong
Java Plateau. The results suggest that unlike today's ocean, sizable
vertical gradients in the carbonate ion concentration existed in the
glacial-age deep ocean. In the equatorial Pacific, the concentration
increased with depth, and in the Atlantic, it decreased with depth. In
addition, the contrast between the carbonate ion concentration in deep
waters produced in the northern Atlantic and deep water in the Pacific
appears to have been larger than in today's ocean.
Lamont-Doherty Earth Observatory of Columbia University,
Palisades, NY 10964, USA.
*
To whom correspondence should be addressed. E-mail:
broecker{at}ldeo.columbia.edu
