ANR WarHol : Glaciers in a warming world: Lessons from Holocene records based on the novel cosmogenic nuclide dating tool “in situ carbon-14”

Funding period: 2015-2020

PI Irene Schimmelpfennig (CEREGE)

Participants at CEREGE : Georges Aumaïtre, Edouard Bard, Lucilla Benedetti, Régis Braucher, Didier Bourlès, Magali Ermini, Yoann Fagault, Vincent Godard, Valéry Guillou, Karim Keddadouche, Laëtitia Léanni, Marie Protin, Thibaut Tuna

Collaborators : Vincent Jomelli (Laboratoire de Géographie Physique, Meudon), Joerg Schaefer (Lamont-Doherty Earth Observatory, USA), Melaine Le Roy (EDYTEM, Chambéry), Philip Deline (EDYTEM, Chambéry), Christian Schlüchter (University of Bern)

Webpage: link

Summary: Among the most worrisome evidence of the current climate change is the rapid retreat of glaciers, a resource for water and contributor to sea level rise. The goal of this project is to provide data on paleo-glacier dynamics and thus to offer a basis to refine glacier models, which aim at predicting future ice retreat. To this end, we develop the new cosmogenic dating tool “in situ ¹⁴C” in France, because it allows us to reconstruct the glacier response to warm periods during the Holocene (past ~12 kyr), which represent a similar analogue to future climate-glacier scenarios. The approach is based on the nuclide pair in situ ¹⁴C/¹⁰Be used to exposure-date recently deglaciated proglacial bedrock and providing information of how long it was ice-free during the Holocene. We apply this novel approach, combined with ¹⁰Be moraine dating, in the European Alps, where glaciers are currently rapidly receding, and produce precise glacier chronologies, allowing the evaluation of the ongoing glacier retreat.