1 Ma of water mass provenance in the South Atlantic Ocean revealed by authigenic neodymium isotopes in ODP 1093 ...
The deep Southern Ocean (SO) circulation is of major significance for understanding of the ocean´s impact on Earth’s climate as uptake and release of CO 2 strongly depend on the redistribution of differently ventilated water masses. Here, we present new authigenic neodymium isotope data (εNd) of...
Main Authors: | , , |
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Format: | Text |
Language: | English |
Published: |
Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
2023
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Online Access: | https://dx.doi.org/10.48380/f5j9-sa92 https://www.dggv.de/e-publikationen/1-ma-of-water-mass-provenance-in-the-south-atlantic-ocean-revealed-by-authigenic-neodymium-isotopes-in-odp-1093 |
Summary: | The deep Southern Ocean (SO) circulation is of major significance for understanding of the ocean´s impact on Earth’s climate as uptake and release of CO 2 strongly depend on the redistribution of differently ventilated water masses. Here, we present new authigenic neodymium isotope data (εNd) of the deep-sea sediment ODP1093 in the Southern Atlantic that reveals several systematic temporal glacial-interglacial changes in a range of 6.3 e-units. Assuming Nd-isotopes as mostly conservative tracer and neglecting possible reginal influences, the observed radiogenic εNd values of up to -2.5 during peak glacial periods suggest a predominance of glacial PDW at depths of >3 km. This results in a volume increase of carbon-rich water, aiding in atmospheric CO 2 drawdown during glacials. The ability of εNd to trace water mass changes relies on the sensitivity of water masses to conservative Nd-isotope mixing. The εNd gradient ΔεNd is here defined as the North-South difference in εNd/10° latitude and is a measure ... |
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