The evolution of the Patagonian Ice Sheet from 35 ka to the Present Day (PATICE). / Davies, Bethan; Darvill, Christopher; Lovell, Harold; Bendle, Jacob; Dowdeswell, Julian A.; Fabel, Derek; Garcia, Juan-Luis; Geiger, Alessa; Glasser, Neil F.; Gheorghiu, Delia; Harrison, Stephan; Hein, Andrew S.; Kaplan, Michael; Martin, Julian; Mendelova, Monika; Palmer, Adrian; Pelto, Mauri; Rodes, Angel; Sagredo, Esteban; Smedley, Rachel; Smellie, John L.; Thorndycraft, Varyl.

In: Earth-Science Reviews, Vol. 204, 103152, 18.03.2020.

Research output: Contribution to journalArticle

E-pub ahead of print

Documents

  • Christopher Darvill
  • Harold Lovell
  • Julian A. Dowdeswell
  • Derek Fabel
  • Juan-Luis Garcia
  • Alessa Geiger
  • Neil F. Glasser
  • Delia Gheorghiu
  • Stephan Harrison
  • Andrew S. Hein
  • Michael Kaplan
  • Monika Mendelova
  • Mauri Pelto
  • Angel Rodes
  • Esteban Sagredo
  • Rachel Smedley
  • John L. Smellie

Abstract

We present PATICE, a GIS database of Patagonian glacial geomorphology and recalibrated chronostratigraphic data. PATICE includes 58,823 landforms and 1,669 geochronological ages, and extends from 38°S to 55°S in southern South America. We use these data to generate new empirical reconstructions of the Patagonian Ice Sheet (PIS) and subsequent ice masses and ice-dammed palaeolakes at 35 ka, 30 ka, 25 ka, 20 ka, 15 ka, 13 ka (synchronous with the Antarctic Cold Reversal), 10 ka, 5 ka, 0.2 ka and 2011 AD. At 35 ka, the PIS covered of 492.6 x103 km2, had a sea level equivalent of ~1,496 mm, was 350 km wide and 2090 km long, and was grounded on the Pacific continental shelf edge. Outlet glacier lobes remained topographically confined and the largest generated the suites of subglacial streamlined bedforms characteristic of ice streams. The PIS reached its maximum extent by 33 – 28 ka from 38°S to 48°S, and earlier, around 47 ka from 48°S southwards. Net retreat from maximum positions began by 25 ka, with ice-marginal stabilisation then at 21 – 18 ka, which was then followed by rapid irreversible deglaciation. By 15 ka, the PIS had separated into disparate ice masses, draining into large ice-dammed lakes along the eastern margin, which strongly influenced rates of recession. Glacial readvances or stabilisations occurred at least at 14 – 13 ka, 11 ka, 6 – 5 ka, 2 – 1 ka, and 0.5 – 0.2 ka. We suggest that 20th century glacial recession (% a-1) is occurring faster than at any time documented during the Holocene.
Original languageEnglish
Article number103152
JournalEarth-Science Reviews
Volume204
Early online date18 Mar 2020
DOIs
Publication statusE-pub ahead of print - 18 Mar 2020
This open access research output is licenced under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

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