Book ChapterDOI
Tracers of Past Ocean Circulation
Reads0
Chats0
TLDR
In this article, a review of the major geochemical methods used to reconstruct past ocean circulation is presented, including carbon isotopic composition and trace metal concentrations in the calcite tests of benthic foraminifera.Abstract:
This chapter reviews the major geochemical methods used to reconstruct past ocean circulation. The carbon isotopic composition and trace metal concentrations in the calcite tests of benthic foraminifera are used to reconstruct the nutrient content of deep water masses. These water mass tracers reflect both biological cycling and physical circulation and mixing in the oceans. Conservative water mass tracers which reflect circulation and mixing alone are also discussed. These tracers include both the isotopic and chemical composition of the benthic foraminifera as well as information from sediment pore waters. Methods for inferring the rates of past ocean circulation are also examined, including radiocarbon, the accumulation of the decay products of uranium in sediments, and geostrophic shear estimates. Finally, the ocean circulation inferred for the Last Glacial Maximum based on these techniques is discussed.read more
Citations
More filters
Book ChapterDOI
Chapter Seven Paleoceanographical Proxies Based on Deep-Sea Benthic Foraminiferal Assemblage Characteristics
TL;DR: In this paper, the authors focus on the paleoceanographic proxies based on deep-sea benthic foraminiferal assemblage characteristics, and present the following three proxy relationships that are promising: those between BFR faunas and BFR oxygenation, export productivity, and deep sea water mass characteristics.
Book ChapterDOI
Chapter 11 – Carbon Isotope Stratigraphy
Matthew R. Saltzman,Ellen Thomas +1 more
TL;DR: In this article, a review of carbon isotope variations through geologic time compiled from multiple literature sources is presented, where the authors consider whether skeletal carbonate secreted by specific organisms or bulk carbonate has been used in evaluating or comparing carbon isotopes stratigraphic records.
Journal ArticleDOI
The Atlantic Meridional Overturning Circulation and Abrupt Climate Change.
TL;DR: The evidence for changes in the strength and structure of the AMOC associated with the Younger Dryas and many of the Heinrich events is strong and the lack of direct evidence for circulation changes over the shortest events leaves the possibility of other driving mechanisms for millennial-scale climate variability.
Journal ArticleDOI
How much did Glacial North Atlantic Water shoal
TL;DR: In this paper, the authors performed a water mass decomposition to quantify the distribution of Glacial North Atlantic Water, where the sparsity of data, geometrical constraints, and non-conservative tracer effects are taken into account, and the extrapolation for the unknown water mass end-members is guided by the modern-day circulation.
References
More filters
Journal ArticleDOI
Oxygen isotope fractionation in divalent metal carbonates
TL;DR: In this article, the fractionation factors for the distribution of 18O between alkaline-earth carbonates and water have been measured over the temperature range 0 −500°C.
Journal ArticleDOI
Equilibrium and nonequilibrium oxygen isotope effects in synthetic carbonates
Sang-Tae Kim,James R. O'Neil +1 more
TL;DR: A suite of divalent metal (Ca, Cd, Ba) carbonates was synthesized over the temperature range 10-40°C by the classical method of slowly bubbling N 2 through a bicarbonate solution.
Journal ArticleDOI
Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes
TL;DR: It is found that the meridional overturning was nearly, or completely, eliminated during the coldest deglacial interval in the North Atlantic region, beginning with the catastrophic iceberg discharge Heinrich event H1, 17,500’yr ago, and declined sharply but briefly into the Younger Dryas cold event, about 12,700 yr ago.
Journal ArticleDOI
Carbon isotope fractionation between dissolved bicarbonate and gaseous carbon-dioxide
TL;DR: In this paper, the stable carbon isotope fractionation between gaseous CO 2 and dissolved bicarbonate has been measured from 5 to 25°C by a method of high precision.