Rapid thinning of the late Pleistocene Patagonian ice sheet followed migration of the Southern Westerlies

Boex, J., Fogwill, C., Harrison, S., Glasser, N.F., Hein, A., Schnabel, C. and Xu, S. (2013) Rapid thinning of the late Pleistocene Patagonian ice sheet followed migration of the Southern Westerlies. Scientific Reports, 3, 2118. (doi: 10.1038/srep02118) (PMID:23817136) (PMCID:PMC3698495)

Abstract

Here we present the first reconstruction of vertical ice-sheet profile changes from any of the Southern Hemisphere's mid-latitude Pleistocene ice sheets. We use cosmogenic radio-nuclide (CRN) exposure analysis to record the decay of the former Patagonian Ice Sheet (PIS) from the Last Glacial Maximum (LGM) and into the late glacial. Our samples, from mountains along an east-west transect to the east of the present North Patagonian Icefield (NPI), serve as ‘dipsticks’ that allow us to reconstruct past changes in ice-sheet thickness, and demonstrates that the former PIS remained extensive and close to its LGM extent in this region until ~19.0 ka. After this time rapid ice-sheet thinning, initiated at ~18.1 ka, saw ice at or near its present dimension by 15.5 ka. We argue this rapid thinning was triggered by a combination of the rapid southward migration of the precipitation bearing Southern Hemisphere (SH) westerlies and regional warming.

• Item Type: Articles
• Additional Information: CRN exposure ages were funded by a NERC CIAF Award to J.B., S.H. and C.J.F. C.J.F. acknowledges a Royal Society Research Grant. Sample preparation was undertaken at the NERC Cosmogenic Isotope Analysis Facility and the University of Exeter Cosmogenic Isotope Lab. J.B. was supported by a NERC postgraduate studentship to S.H. and C.J.F. acknowledges the support of ARC awards FL100100195 and FT 120100004.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Schnabel, Dr Christoph and Xu, Dr Sheng
• Authors: Boex, J., Fogwill, C., Harrison, S., Glasser, N.F., Hein, A., Schnabel, C., and Xu, S.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Scientific Reports
• Publisher: Nature Publishing Group
• ISSN: 2045-2322
• ISSN (Online): 2045-2322
• Copyright Holders: Copyright © 2013 The Authors
• First Published: First published in Scientific Reports 3: 2118
• Publisher Policy: Reproduced under a Creative Commons License