Glacier response to the Little Ice Age during the Neoglacial cooling in Greenland

• Published in: Earth-Science Reviews
• Main Authors: Kjær, Kurt H., Bjørk, Anders A., Kjeldsen, Kristian K., Hansen, Eric S., Andresen, Camilla S., Siggaard-Andersen, Marie Louise, Khan, Shfaqat A., Søndergaard, Anne Sofie, Colgan, William, Schomacker, Anders, Woodroffe, Sarah, Funder, Svend, Rouillard, Alexandra, Jensen, Jens Fog, Larsen, Nicolaj K.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: Greenland Ice Sheet; Ice marginal fluctuations; Little Ice Age; Neoglacial; glacier; Greenland; Ice Sheet; Sea ice
• Online Access: https://pure.au.dk/portal/da/publications/glacier-response-to-the-little-ice-age-during-the-neoglacial-cooling-in-greenland(f56f1721-3ccd-4172-83dd-e8ca27861f8e).html; https://doi.org/10.1016/j.earscirev.2022.103984; https://pure.au.dk/ws/files/342346420/1-s2.0-S001282522200068X-main.pdf

In the Northern Hemisphere, an insolation driven Early to Middle Holocene Thermal Maximum was followed by a Neoglacial cooling that culminated during the Little Ice Age (LIA). Here, we review the glacier response to this Neoglacial cooling in Greenland. Changes in the ice margins of outlet glaciers from the Greenland Ice Sheet as well as local glaciers and ice caps are synthesized Greenland-wide. In addition, we compare temperature reconstructions from ice cores, elevation changes of the ice sheet across Greenland and oceanographic reconstructions from marine sediment cores over the past 5,000 years. The data are derived from a comprehensive review of the literature supplemented with unpublished reports. Our review provides a synthesis of the sensitivity of the Greenland ice margins and their variability, which is critical to understanding how Neoglacial glacier activity was interrupted by the current anthropogenic warming. We have reconstructed three distinct periods of glacier expansion from our compilation: two older Neoglacial advances at 2,500 – 1,700 yrs. BP (Before Present = 1950 CE, Common Era) and 1,250 – 950 yrs. BP; followed by a general advance during the younger Neoglacial between 700-50 yrs. BP, which represents the LIA. There is still insufficient data to outline the detailed spatio-temporal relationships between these periods of glacier expansion. Many glaciers advanced early in the Neoglacial and persisted in close proximity to their present-day position until the end of the LIA. Thus, the LIA response to Northern Hemisphere cooling must be seen within the wider context of the entire Neoglacial period of the past 5,000 years. Ice expansion appears to be closely linked to changes in ice sheet elevation, accumulation, and temperature as well as surface-water cooling in the surrounding oceans. At least for the two youngest Neoglacial advances, volcanic forcing triggering a sea-ice /ocean feedback, could explain their initiation. There are probably several LIA glacier fluctuations since the first ...