Articles | Volume 20, issue 8
https://doi.org/10.5194/cp-20-1861-2024
https://doi.org/10.5194/cp-20-1861-2024
Research article
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28 Aug 2024
Research article | Highlight paper |  | 28 Aug 2024

Late Quaternary glacial maxima in southern Patagonia: insights from the Lago Argentino glacier lobe

Matias Romero, Shanti B. Penprase, Maximillian S. Van Wyk de Vries, Andrew D. Wickert, Andrew G. Jones, Shaun A. Marcott, Jorge A. Strelin, Mateo A. Martini, Tammy M. Rittenour, Guido Brignone, Mark D. Shapley, Emi Ito, Kelly R. MacGregor, and Marc W. Caffee

Data sets

Shapefiles of Lago Argentino - Rio Santa Cruz glacial landforms Matias Romero et al. https://doi.org/10.5281/zenodo.11556612

The NCEP/NCAR 40-Year Reanalysis Project (https://psl.noaa.gov/data/gridded/data.ncep.reanalysis.html) E. Kalnay et al. https://doi.org/10.1175/1520-0477(1996)077<0437:TNYRP>2.0.CO;2

Modelo Digital de Elevaciones Instituto Geográfico Nacional https://www.ign.gob.ar/NuestrasActividades/Geodesia/ModeloDigitalElevaciones/Introduccion

GEBCO 2024 Grid GEBCO Compilation Group https://doi.org/10.5285/1c44ce99-0a0d-5f4f-e063-7086abc0ea0f

ETOPO 2022 15 Arc-Second Global Relief Model NOAA National Centers for Environmental Information https://doi.org/10.25921/fd45-gt74

Model code and software

Insolation, The Climate Laboratory B. E. J. Rose https://climlab.readthedocs.io/en/latest/index.html

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Co-editor-in-chief
Romero et al. mapped geomorphological features on the landscape and dated moraine boulders and outwash sediments to constrain past changes of the former Patagonian Ice Sheet in southern Argentina. They show that the Lago Argentino glacier expanded during Marine Isotope Stage 6 (153.0±14.7 ka) and during Marine Isotope Stage 3, culminating at 44.5±8.0 ka and at 36.6±1.0 ka, thus preceding the Last Glacial Maximum. They hypothesize that this was a result of longer and colder winters, as well as increased precipitation resulting from an equatorward shift of the Southern Hemisphere Westerlies.
Short summary
Investigating past glaciated regions is crucial for understanding how ice sheets responded to climate forcings and how they might respond in the future. We use two independent dating techniques to document the timing and extent of the Lago Argentino glacier lobe, a former lobe of the Patagonian Ice Sheet, during the late Quaternary. Our findings highlight feedbacks in the Earth’s system responsible for modulating glacier growth in the Southern Hemisphere prior to the global Last Glacial Maximum.