Data_Sheet_2_Exceptional Retreat of Kangerlussuaq Glacier, East Greenland, Between 2016 and 2018.docx

• Main Authors: Stephen Brough, J. Rachel Carr, Neil Ross, James M. Lea
• Format: Dataset
• Language: unknown
• Published: 2019
• Subjects: Solid Earth Sciences; Climate Science; Atmospheric Sciences not elsewhere classified; Exploration Geochemistry; Inorganic Geochemistry; Isotope Geochemistry; Organic Geochemistry; Geochemistry not elsewhere classified; Igneous and Metamorphic Petrology; Ore Deposit Petrology; Palaeontology (incl. Palynology); Structural Geology; Tectonics; Volcanology; Geology not elsewhere classified; Seismology and Seismic Exploration; Glaciology; Hydrogeology; Natural Hazards; Quaternary Environments; Earth Sciences not elsewhere classified; Evolutionary Impacts of Climate Change; Greenland ice sheet; marine-terminating glaciers; basal topography; ice discharge; mass balance; glacier retreat; sea level rise; remote sensing; Greenland; Kangerlussuaq; East Greenland; glacier; Ice Sheet; Tidewater
• Online Access: https://doi.org/10.3389/feart.2019.00123.s002; https://figshare.com/articles/Data_Sheet_2_Exceptional_Retreat_of_Kangerlussuaq_Glacier_East_Greenland_Between_2016_and_2018_docx/8208560

Kangerlussuaq Glacier is one of Greenland’s largest tidewater outlet glaciers, accounting for approximately 5% of all ice discharge from the Greenland ice sheet. In 2018 the Kangerlussuaq ice front reached its most retreated position since observations began in 1932. We determine the relationship between retreat and: (i) ice velocity; and (ii) surface elevation change, to assess the impact of the retreat on the glacier trunk. Between 2016 and 2018 the glacier retreated ∼5 km and brought the Kangerlussuaq ice front into a major (∼15 km long) overdeepening. Coincident with this retreat, the glacier thinned as a result of near-terminus acceleration in ice flow. The subglacial topography means that 2016–2018 terminus recession is likely to trigger a series of feedbacks between retreat, thinning, and glacier acceleration, leading to a rapid and high-magnitude increase in discharge and sea level rise contribution. Dynamic thinning may continue until the glacier reaches the upward sloping bed ∼10 km inland of its current position. Incorporating these non-linear processes into prognostic models of the ice sheet to 2100 and beyond will be critical for accurate forecasting of the ice sheet’s contribution to sea level rise.