Younger Dryas glacier advances in the tropical Andes driven by increased precipitation
There is currently a debate about the timing and drivers of former glacier behaviour and climate change in the tropical Andes. Using <sup>10</sup>Be dating we determined the ages of 21 boulders on moraines in the Santa Cruz Valley, Peru (∼10°S, altitudes ~ 4100 to ~ 4300 m a.s.l.). Former glacier extent is marked by a suite of nested outer lateral and terminal moraines. These moraines are dated to 11.1 ka, 11.6 ka, 11.8 ka and 12.0 ka, falling within the Younger Dryas Chronozone (YDC; ∼12.9-11.6 ka). Nine <sup>10</sup>Be samples from the Lake Arhuaycocha catchment document a period of glacier thinning and lateral contraction between 12.0 ka and 11.8 ka. Reconstructed glacier Equilibrium Line Altitudes (ELA) at 11.0 to 12.0 ka with an area-altitude balance ratio (AABR) of 1.00-2.50 are between 4675 and 4835 m a.s.l. for the Arhuaycocha glacier, between 4692 and 4832 m a.s.l. for the Taullicocha glacier and between 4800 and 4940 m a.s.l. for the Artizon glacier. These values represent a depression of 300-400 m in elevation compared to contemporary values for the ELA. We infer that the glacier advances at this time were driven by increased precipitation and that these changes were most likely a response to seasonal changes in the position of the ITCZ.
Authors
- Costanza Del Gobbo (ORCID: https://orcid.org/0000-0001-6380-0767)
- Dylan H. Rood (ORCID: https://orcid.org/0000-0002-4425-4702)
- Matthew W. Peacey (ORCID: https://orcid.org/0000-0001-8554-2797)
- Keir A. Nichols (ORCID: https://orcid.org/0000-0002-9447-9918)
- Harrinson Jara (ORCID: https://orcid.org/0000-0001-6167-6379)
- Renato R. Colucci (ORCID: https://orcid.org/0000-0001-8344-5723)
- Stephan Harrison (ORCID: https://orcid.org/0000-0003-2820-7313)
- Christian Riveros (ORCID: https://orcid.org/0000-0003-4810-1209)
- Andrea Securo (ORCID: https://orcid.org/0000-0001-6297-2233)
- Ryan Wilson
- Neil F. Glasser (ORCID: https://orcid.org/0000-0002-8245-2670)
- Hilbert Villafane (ORCID: https://orcid.org/0000-0001-7359-9438)
- Joanne L. Wood (ORCID: https://orcid.org/0000-0002-6453-9350)
- Manuel Cosi
- Judith Torres
- Enver Melgarejo
Institutions
- University of Huddersfield (GB)
- University of Trieste (IT)
- Ca' Foscari University of Venice (IT)
- Université du Québec à Montréal (CA)
- Aberystwyth University (GB)
- University of Exeter (GB)
- Instituto Nacional de Investigación en Glaciares y Ecosistemas de Montaña (PE)
- Scottish Universities Environmental Research Centre (GB)
- Imperial College London (GB)
- University of Glasgow (GB)
Publication Details
- Journal
- Scientific Reports
- Published
- 2025-08-22
- DOI
- https://doi.org/10.1038/s41598-025-16603-3
- Citations
- 1
- Primary Topic
- Geology and Paleoclimatology Research
- Type
- article
- Field-Weighted Citation Impact
- 1.30
Funders
- Natural Environment Research Council