A chronology of Holocene and Little Ice Age glacier culminations of the Steingletscher, Central Alps, Switzerland, based on high-sensitivity beryllium-10 moraine dating

Abstract

The amplitude and timing of past glacier culminations are sensitive recorders of key climate events on a regional scale. Precisely dating young moraines using cosmogenic nuclides to investigate Holocene glacier chronologies has proven challenging, but progress in the high-sensitivity 10Be technique has recently been shown to enable the precise dating of moraines as young as a few hundred years. In this study we use 10Be moraine dating to reconstruct culminations of the Steingletscher, a small mountain glacier in the central Swiss Alps, throughout the Holocene. The outermost-recorded positions of Steingletscher most likely occurred in the Early Holocene and appear nearly synchronous with glacier culminations reported from other regions in the Alps. A Late-Holocene position corroborates the evidence for a significant glacier advance of similar extent to that of the Little Ice Age (LIA) ∼3 kyr ago. Finally, fourteen boulders from different moraines yield 10Be ages between 580 and 140 years with analytical precisions mostly <10%, dating Steingletscher advances during the LIA. Because these LIA 10Be ages are in stratigraphic order, we tentatively distinguish four LIA glacier culminations: about 1470 CE, 1650 CE, 1750 CE and 1820 CE, which are in good agreement with existing independent records during the LIA in the Swiss Alps. These findings illustrate the high potential of the 10Be moraine dating method to directly link paleo-glacier-chronologies to historical records and thus present-day glacier evolution.