Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years.
Disentangling inputs of aeolian dust, ice-rafted debris (IRD), and eroded continental detritus delivered by ocean currents to marine sediments provide important insights into Earth System processes and climate. This study uses Sr-Nd-Pb isotope ratios of the continent-derived (lithogenic) fraction in...
Published in: | Proceedings of the National Academy of Sciences |
---|---|
Main Authors: | , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Atypon
2024
|
Subjects: | |
Online Access: | https://doi.org/10.1073/pnas.2402120121 https://pubmed.ncbi.nlm.nih.gov/39042680 |
id |
ftpubmed:39042680 |
---|---|
record_format |
openpolar |
spelling |
ftpubmed:39042680 2024-09-09T19:07:38+00:00 Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years. Barkley, Anne E Winckler, Gisela Recasens, Cristina Kaplan, Michael R Koffman, Bess G Calabozo, Fernando Middleton, Jennifer L Anderson, Robert F Cai, Yue Bolge, Louise Longman, Jack Goldstein, Steven L 2024 Jul 30 https://doi.org/10.1073/pnas.2402120121 https://pubmed.ncbi.nlm.nih.gov/39042680 eng eng Atypon https://doi.org/10.1073/pnas.2402120121 https://pubmed.ncbi.nlm.nih.gov/39042680 Proc Natl Acad Sci U S A ISSN:1091-6490 Volume:121 Issue:31 Southern Ocean climate dust ice-rafted debris provenance Journal Article 2024 ftpubmed https://doi.org/10.1073/pnas.2402120121 2024-07-24T16:03:00Z Disentangling inputs of aeolian dust, ice-rafted debris (IRD), and eroded continental detritus delivered by ocean currents to marine sediments provide important insights into Earth System processes and climate. This study uses Sr-Nd-Pb isotope ratios of the continent-derived (lithogenic) fraction in deep-sea core TN057-6 from the subantarctic Southern Ocean southwest of Africa over the past 150,000 y to identify source regions and quantify their relative contributions and fluxes utilizing a mixing model set in a Bayesian framework. The data are compared with proxies from parallel core Ocean Drilling Program Site 1090 and newly presented data from potential South America aeolian dust source areas (PSAs), allowing for an integrated investigation into atmospheric, oceanic, and cryospheric dynamics. PSA inputs varied on glacial/interglacial timescales, with southern South American sources dominating up to 88% of the lithogenic fraction (mainly Patagonia, which provided up to 68%) during cold periods, while southern African sources were more important during interglacials. During the warmer Marine Isotope Stage (MIS) 3 of the last glacial period, lithogenic fluxes were twice that of colder MIS2 and MIS4 at times, and showed unique isotope ratios best explained by Antarctic-derived IRD, likely from the Weddell Sea. The IRD intrusions contributed up to 41% at times and followed Antarctic millennial warming events that raised temperatures, causing instability of icesheet margins. High IRD was synchronous with increased bioavailable iron, nutrient utilization, high biological productivity, and decreased atmospheric CO2. Overall, TN057-6 sediments record systematic Southern Hemisphere climate shifts and cryospheric changes that impacted biogeochemical cycling on both glacial/interglacial and subglacial timescales. Article in Journal/Newspaper Antarc* Antarctic South Atlantic Ocean Southern Ocean Weddell Sea PubMed Central (PMC) Antarctic Southern Ocean Weddell Sea Patagonia Weddell Proceedings of the National Academy of Sciences 121 31 |
institution |
Open Polar |
collection |
PubMed Central (PMC) |
op_collection_id |
ftpubmed |
language |
English |
topic |
Southern Ocean climate dust ice-rafted debris provenance |
spellingShingle |
Southern Ocean climate dust ice-rafted debris provenance Barkley, Anne E Winckler, Gisela Recasens, Cristina Kaplan, Michael R Koffman, Bess G Calabozo, Fernando Middleton, Jennifer L Anderson, Robert F Cai, Yue Bolge, Louise Longman, Jack Goldstein, Steven L Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years. |
topic_facet |
Southern Ocean climate dust ice-rafted debris provenance |
description |
Disentangling inputs of aeolian dust, ice-rafted debris (IRD), and eroded continental detritus delivered by ocean currents to marine sediments provide important insights into Earth System processes and climate. This study uses Sr-Nd-Pb isotope ratios of the continent-derived (lithogenic) fraction in deep-sea core TN057-6 from the subantarctic Southern Ocean southwest of Africa over the past 150,000 y to identify source regions and quantify their relative contributions and fluxes utilizing a mixing model set in a Bayesian framework. The data are compared with proxies from parallel core Ocean Drilling Program Site 1090 and newly presented data from potential South America aeolian dust source areas (PSAs), allowing for an integrated investigation into atmospheric, oceanic, and cryospheric dynamics. PSA inputs varied on glacial/interglacial timescales, with southern South American sources dominating up to 88% of the lithogenic fraction (mainly Patagonia, which provided up to 68%) during cold periods, while southern African sources were more important during interglacials. During the warmer Marine Isotope Stage (MIS) 3 of the last glacial period, lithogenic fluxes were twice that of colder MIS2 and MIS4 at times, and showed unique isotope ratios best explained by Antarctic-derived IRD, likely from the Weddell Sea. The IRD intrusions contributed up to 41% at times and followed Antarctic millennial warming events that raised temperatures, causing instability of icesheet margins. High IRD was synchronous with increased bioavailable iron, nutrient utilization, high biological productivity, and decreased atmospheric CO2. Overall, TN057-6 sediments record systematic Southern Hemisphere climate shifts and cryospheric changes that impacted biogeochemical cycling on both glacial/interglacial and subglacial timescales. |
format |
Article in Journal/Newspaper |
author |
Barkley, Anne E Winckler, Gisela Recasens, Cristina Kaplan, Michael R Koffman, Bess G Calabozo, Fernando Middleton, Jennifer L Anderson, Robert F Cai, Yue Bolge, Louise Longman, Jack Goldstein, Steven L |
author_facet |
Barkley, Anne E Winckler, Gisela Recasens, Cristina Kaplan, Michael R Koffman, Bess G Calabozo, Fernando Middleton, Jennifer L Anderson, Robert F Cai, Yue Bolge, Louise Longman, Jack Goldstein, Steven L |
author_sort |
Barkley, Anne E |
title |
Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years. |
title_short |
Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years. |
title_full |
Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years. |
title_fullStr |
Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years. |
title_full_unstemmed |
Patagonian dust, Agulhas Current, and Antarctic ice-rafted debris contributions to the South Atlantic Ocean over the past 150,000 years. |
title_sort |
patagonian dust, agulhas current, and antarctic ice-rafted debris contributions to the south atlantic ocean over the past 150,000 years. |
publisher |
Atypon |
publishDate |
2024 |
url |
https://doi.org/10.1073/pnas.2402120121 https://pubmed.ncbi.nlm.nih.gov/39042680 |
geographic |
Antarctic Southern Ocean Weddell Sea Patagonia Weddell |
geographic_facet |
Antarctic Southern Ocean Weddell Sea Patagonia Weddell |
genre |
Antarc* Antarctic South Atlantic Ocean Southern Ocean Weddell Sea |
genre_facet |
Antarc* Antarctic South Atlantic Ocean Southern Ocean Weddell Sea |
op_source |
Proc Natl Acad Sci U S A ISSN:1091-6490 Volume:121 Issue:31 |
op_relation |
https://doi.org/10.1073/pnas.2402120121 https://pubmed.ncbi.nlm.nih.gov/39042680 |
op_doi |
https://doi.org/10.1073/pnas.2402120121 |
container_title |
Proceedings of the National Academy of Sciences |
container_volume |
121 |
container_issue |
31 |
_version_ |
1809821779464552448 |