A first constraint on basal melt-water production of the Greenland ice sheet

• Published in: Nature Communications
• Main Authors: Karlsson, Nanna, Solgaard, Anne, Mankoff, Kenneth, Gillet-Chaulet, Fabien, Macgregor, Joseph, Box, Jason, Citterio, Michele, Colgan, William, Larsen, Signe, Kjeldsen, Kristian, Korsgaard, Niels, Benn, Douglas, Hewitt, Ian, Fausto, Robert
• Other Authors: Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology; Arctic; Greenland; Ice Sheet
• Online Access: https://hal.science/hal-03382448; https://hal.science/hal-03382448/document; https://hal.science/hal-03382448/file/Karlsson%20et%20al.%20-%202021%20-%20A%20first%20constraint%20on%20basal%20melt-water%20production%20.pdf; https://doi.org/10.1038/s41467-021-23739-z

International audience The Greenland ice sheet has been one of the largest sources of sea-level rise since the early 2000s. However, basal melt has not been included explicitly in assessments of ice-sheet mass loss so far. Here, we present the first estimate of the total and regional basal melt produced by the ice sheet and the recent change in basal melt through time. We find that the ice sheet's present basal melt production is 21.4 +4.4/−4.0 Gt per year, and that melt generated by basal friction is responsible for about half of this volume. We estimate that basal melting has increased by 2.9 ± 5.2 Gt during the first decade of the 2000s. As the Arctic warms, we anticipate that basal melt will continue to increase due to faster ice flow and more surface melting thus compounding current mass loss trends, enhancing solid ice discharge, and modifying fjord circulation.