Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka
The most explosive volcanic event of the Quaternary was the eruption of Mt. Toba, Sumatra, 75,000 y ago, which produced voluminous ash deposits found across much of the Indian Ocean, Indian Peninsula, and South China Sea. A major climatic downturn observed within the Greenland ice cores has been att...
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ftumanchesterpub:oai:pure.atira.dk:publications/186e3c2d-7a07-4912-8b9b-f19e4e48b4b1 2023-11-12T04:18:00+01:00 Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka Lane, Christine S. Chorn, Ben T. Johnson, Thomas C. 2013-05-14 application/octet-stream https://research.manchester.ac.uk/en/publications/186e3c2d-7a07-4912-8b9b-f19e4e48b4b1 https://doi.org/10.1073/pnas.1301474110 https://pure.manchester.ac.uk/ws/files/27630865/POST-PEER-REVIEW-PUBLISHERS.PDF http://www.pnas.org/content/110/20/8025.full.pdf+html eng eng info:eu-repo/semantics/openAccess Lane , C S , Chorn , B T & Johnson , T C 2013 , ' Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka ' , Proceedings of the National Academy of Sciences of the United States of America , vol. 110 , no. 20 , pp. 8025-8029 . https://doi.org/10.1073/pnas.1301474110 article 2013 ftumanchesterpub https://doi.org/10.1073/pnas.1301474110 2023-10-30T09:14:15Z The most explosive volcanic event of the Quaternary was the eruption of Mt. Toba, Sumatra, 75,000 y ago, which produced voluminous ash deposits found across much of the Indian Ocean, Indian Peninsula, and South China Sea. A major climatic downturn observed within the Greenland ice cores has been attributed to the cooling effects of the ash and aerosols ejected during the eruption of the Youngest Toba Tuff (YTT). These events coincided roughly with a hypothesized human genetic bottleneck, when the number of our species in Africa may have been reduced to near extinction. Some have speculated that the demise of early modern humans at that time was due in part to a dramatic climate shift triggered by the supereruption. Others have argued that environmental conditions would not have been so severe to have such an impact on our ancestors, and furthermore, that modern humans may have already expanded beyond Africa by this time. We report an observation of the YTT in Africa, recovered as a cryptotephra layer in Lake Malawi sediments, >7,000 km west of the source volcano. The YTT isochron provides an accurate and precise age estimate for the Lake Malawi paleoclimate record, which revises the chronology of past climatic events in East Africa. The YTT in Lake Malawi is not accompanied by a major change in sediment composition or evidence for substantial temperature change, implying that the eruption did not significantly impact the climate of East Africa and was not the cause of a human genetic bottleneck at that time. Article in Journal/Newspaper Greenland Greenland ice cores The University of Manchester: Research Explorer Greenland Indian Proceedings of the National Academy of Sciences 110 20 8025 8029 |
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The University of Manchester: Research Explorer |
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English |
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The most explosive volcanic event of the Quaternary was the eruption of Mt. Toba, Sumatra, 75,000 y ago, which produced voluminous ash deposits found across much of the Indian Ocean, Indian Peninsula, and South China Sea. A major climatic downturn observed within the Greenland ice cores has been attributed to the cooling effects of the ash and aerosols ejected during the eruption of the Youngest Toba Tuff (YTT). These events coincided roughly with a hypothesized human genetic bottleneck, when the number of our species in Africa may have been reduced to near extinction. Some have speculated that the demise of early modern humans at that time was due in part to a dramatic climate shift triggered by the supereruption. Others have argued that environmental conditions would not have been so severe to have such an impact on our ancestors, and furthermore, that modern humans may have already expanded beyond Africa by this time. We report an observation of the YTT in Africa, recovered as a cryptotephra layer in Lake Malawi sediments, >7,000 km west of the source volcano. The YTT isochron provides an accurate and precise age estimate for the Lake Malawi paleoclimate record, which revises the chronology of past climatic events in East Africa. The YTT in Lake Malawi is not accompanied by a major change in sediment composition or evidence for substantial temperature change, implying that the eruption did not significantly impact the climate of East Africa and was not the cause of a human genetic bottleneck at that time. |
format |
Article in Journal/Newspaper |
author |
Lane, Christine S. Chorn, Ben T. Johnson, Thomas C. |
spellingShingle |
Lane, Christine S. Chorn, Ben T. Johnson, Thomas C. Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka |
author_facet |
Lane, Christine S. Chorn, Ben T. Johnson, Thomas C. |
author_sort |
Lane, Christine S. |
title |
Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka |
title_short |
Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka |
title_full |
Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka |
title_fullStr |
Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka |
title_full_unstemmed |
Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka |
title_sort |
ash from the toba supereruption in lake malawi shows no volcanic winter in east africa at 75 ka |
publishDate |
2013 |
url |
https://research.manchester.ac.uk/en/publications/186e3c2d-7a07-4912-8b9b-f19e4e48b4b1 https://doi.org/10.1073/pnas.1301474110 https://pure.manchester.ac.uk/ws/files/27630865/POST-PEER-REVIEW-PUBLISHERS.PDF http://www.pnas.org/content/110/20/8025.full.pdf+html |
geographic |
Greenland Indian |
geographic_facet |
Greenland Indian |
genre |
Greenland Greenland ice cores |
genre_facet |
Greenland Greenland ice cores |
op_source |
Lane , C S , Chorn , B T & Johnson , T C 2013 , ' Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka ' , Proceedings of the National Academy of Sciences of the United States of America , vol. 110 , no. 20 , pp. 8025-8029 . https://doi.org/10.1073/pnas.1301474110 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1073/pnas.1301474110 |
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Proceedings of the National Academy of Sciences |
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110 |
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20 |
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8025 |
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