Mountain glacier fluctuations during the Lateglacial and Holocene on Clavering Island (northeastern Greenland) from ¹⁰Be moraine dating

Abstract

Despite an increasing interest in Greenlandic mountain glaciers over recent decades, their evolution during the Lateglacial and Holocene still needs to be better constrained. Here we present 25 10Be cosmic‐ray exposure (CRE) ages of boulders collected on moraines from three glaciers located on Clavering Island (northeastern Greenland). CRE ages span 16.29±0.79 to 0.37±0.05 ka and reveal three periods of moraine formation during the Lateglacial, the Early and the Late Holocene. Data show a multi‐modal distribution of the ages during the Lateglacial with exposure ages spanning from 16.29±0.79 to 12.31±1.3 ka. At least two glaciers experienced a greater expansion at the beginning of the Holocene than at the end of the Holocene, dated to 11.3±0.3 and 10.8±0.6 ka, respectively. At the end of the Holocene, glacial advances occurred during the Dark Ages Cold Period and during the Little Ice Age (LIA), synchronous with glacial advances documented in nearby lake sediments. This new CRE chronology highlights that the LIA extent is not the largest glacier advance in the Late Holocene in Clavering Island. This broadly corresponds with other mountain glaciers of western and northern Greenland, and does not appear to reflect northern high latitude summer insolation that would suggest progressive temperature decrease, but instead mimics recent regional continental temperature reconstructions that show a long term warming driven by different forcing.

Early Holocene cold snaps and their expression in the moraine record of the eastern European Alps

“…This timing coincides with prominent episodes of glacier advance in the Western Alps, most notably at the Aletsch glacier (Holzhauser et al, 2005) and at the Miage and Mer de Glace, both in the Mont Blanc massif (Deline and Orombelli, 2005;Le Roy et al, 2015). Concurrent glacier advances have also been reported from Alaska, Iceland, Scandinavia, and Greenland (Barclay et al, 2009;Biette et al, 2020;Solomina et al, 2016). Glacier advance during this period is consistent with decreasing summer temperatures (Fig.…”

“…12 and 10 ka, which implies substantial large-scale cooling during this period. This pattern of EH moraine stabilization is not limited to the Alpine realm but has been observed in other places in the North Atlantic and Arctic region, for instance along the Fennoscandian ice sheet (e.g., Briner et al, 2014;Nesje, 2009), the Icelandic ice sheet (e.g., Sigfusdottir and Benediktsson, 2020), at Svalbard (e.g., Farnsworth et al, 2020), along the eastern part of the LIS (e.g., Corbett et al, 2016;Ullman et al, 2016;Young et al, 2020), and along the Greenland ice sheet (e.g., Biette et al, 2020;Levy et al, 2016;Young et al, 2020) (Fig. 9g).…”

Early Holocene cold snaps and their expression in the moraine record of the Eastern European Alps

“…This timing coincides with prominent episodes of glacier advance in the Western Alps, most notably at the Aletsch glacier (Holzhauser et al, 2005), and at the Miage and Mer de Glace, both in the Mont Blanc massif (Deline and Orombelli, 2005;Le Roy et al, 2015). Concurrent glacier advances have also been reported from Alaska, Iceland, Scandinavia and from Greenland (Biette et al, 2020;Barclay et al, 2009;Solomina et al, 2016). Glacier advance during this period is consistent with decreasing summer temperatures (Fig.…”

“…Young et al, 2020;Corbett et al, 2016;Ullman et al, 2016) and along the Greenland ice sheet (e.g. Young et al, 2020;Biette et al, 2020;Levy et al, 2016) (Fig. 9g).…”

“…Resulting freshwater input may have weakened the AMOC, which in turn lead to a drop in mean annual temperatures in Greenland and moraine formation in the Arctic (e.g. Young et al, 2020;Biette et al, 2020). Temperatures in the Alps decreased or stagnated around that time (Fig.…”