A global environmental crisis 42,000 years ago
Authors: Ken McCracken
Paolo Sebastianelli
Julien G Anet
Timothy J Heaton
Janet Wilmshurst
Christopher Bronk Ramsey
Alan Hogg
Florian Adolphi
J Tyler Faith
Thomas Peter
Alan Cooper
Pavla Fenwick
Yassine Souilmi
Matt McGlone
Raimund Muscheler
Mathew Lipson
Eugene Rozanov
Jiabo Liu
Marina Friedel
Norbert Nowaczyk
Christopher J Fogwill
Anthony Dosseto
Roland Zech
Jonathan Palmer
Chris S M Turney
Andrew M Lorrey
Konrad Hughen
Zo√´ Thomas
James M Russell
Ivo Suter
Raymond Tobler
Janelle Stevenson
Eleanor Rainsley
Journal: Science (2021)
Discipline: Multidisciplinary
Keywords: Geological archives; Earth's magnetic poles; radiocarbon calibration; Laschamps Excursion; New Zealand kauri trees
Affiliations: South Australian Museum, Adelaide, SA 5000, Australia., BlueSky Genetics, PO Box 287, Adelaide, SA 5137, Australia., Chronos Carbon-Cycle Facility, and Earth and Sustainability Science Research Centre, University of New South Wales, Sydney, NSW 2052, Australia., Radiocarbon Dating Laboratory, University of Waikato, Hamilton 3240, New Zealand., Landcare Research, PO Box 69040, Lincoln, New Zealand., School of Environment, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand., National Institute of Water and Atmospheric Research Ltd, Auckland 1010, New Zealand., School of Mathematics and Statistics, University of Sheffield, Sheffield S3 7RH, UK., Department of Geological Sciences, Brown University, Providence, RI 02912, USA., University of New South Wales, Sydney, NSW 2052, Australia., Zurich University of Applied Sciences, Centre for Aviation, 8401 Winterthur, Switzerland., Institute for Atmospheric and Climatic Science, ETH Zurich, 8006 Zurich, Switzerland., Physikalisch-Meteorologisches Observatorium Davos and World Radiation Center, 7260 Davos, Switzerland., Department of Physics of Earth, Faculty of Physics, St. Petersburg State University, St. Petersburg 198504, Russia., Swiss Federal Laboratories for Materials Science and Technology (Empa), 8600 D√ºbendorf, Switzerland., Department of Geology, Quaternary Sciences, Lund University, 22362 Lund, Sweden., Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany., Wollongong Isotope Geochronology Laboratory, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW 2522, Australia., Natural History Museum of Utah and Department of Anthropology, University of Utah, Salt Lake City, UT 84108, USA., Gondwana Tree-Ring Laboratory, PO Box 14, Little River, Canterbury 7546, New Zealand., School of Geography, Geology and the Environment, University of Keele, Keele, Staffordshire ST5 5BG, UK., Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA., Centre of Excellence for Climate System Science, University of New South Wales, Sydney, NSW 2052, Australia., Southern University of Science and Technology, Department of Ocean Science and Engineering, Shenzhen 518055, China., Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Section 4.3, 14473 Potsdam, Germany., Research Laboratory for Archaeology and the History of Art, School of Archaeology, University of Oxford, OX1 3TG, UK., Faculty of Mathematics, Astronomy and Physics (FAMAF), National University of Cordoba, X5000HUA, Argentina., Australian Centre for Ancient DNA, University of Adelaide, Adelaide, SA 5000, Australia., Archaeology and Natural History, School of Culture History and Language, ANU College of Asia and the Pacific, Canberra, ACT 2601, Australia., Australia ARC Centre of Excellence for Australian Biodiversity and Heritage, Australian National University, ACT 2601, Australia., Institute of Geography, Friedrich-Schiller-University Jena, 07743 Jena, Germany.

Abstract:  Geological archives record multiple reversals of Earth's magnetic poles, but the global impacts of these events, if any, remain unclear. Uncertain radiocarbon calibration has limited investigation of the potential effects of the last major magnetic inversion, known as the Laschamps Excursion [41 to 42 thousand years ago (ka)]. We use ancient New Zealand kauri trees (Agathis australis) to develop a detailed record of atmospheric radiocarbon levels across the Laschamps Excursion. We precisely characterize the geomagnetic reversal and perform global chemistry-climate modeling and detailed radiocarbon dating of paleoenvironmental records to investigate impacts. We find that geomagnetic field minima ~42 ka, in combination with Grand Solar Minima, caused substantial changes in atmospheric ozone concentration and circulation, driving synchronous global climate shifts that caused major environmental changes, extinction events, and transformations in the archaeological record. 

Retracted: No

PubPeer comments:
 For Figure 9, the images were edited and reused stating different conditions. The images were dragged to show the wall thickening of the aorta and compressed to show the shortening of the aorta. The similarities were shown with colors and for a more detailed analysis, the circles were represented. Could the authors clarify?  , 
 The mRNA expression images (3A and 4A) are exactly the same as the western blots (3C and 4C). Though the upper lane of 4A is unsure, the GAPDH is exactly the same as 3A. In addition, 3C and 4C are exactly the same. In Fig 6, the IL-1b and TNF-a has similarities. The same GAPDH for 3A and 4A. Could the authors clarify?  ,