Sea ice breakup and marine melt of a retreating tidewater outlet glacier in northeast Greenland (81°N)

• Published in: Scientific Reports
• Main Authors: Jørgen Bendtsen, John Mortensen, Kunuk Lennert, Jens K. Ehn, Wieter Boone, Virginie Galindo, Yu-bin Hu, Igor A. Dmitrenko, Sergei A. Kirillov, Kristian K. Kjeldsen, Yngve Kristoffersen, David G. Barber, Søren Rysgaard
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Portfolio 2017
• Subjects: Medicine; R; Science; Q; Arctic; Arctic Ocean; Flade Isblink; Greenland; glacier; Ice cap; Ice Sheet; Ice Shelf; Sea ice; Tidewater
• Online Access: https://doi.org/10.1038/s41598-017-05089-3; https://doaj.org/article/47590520a4bb40d7a576d60fe250c65a

Abstract Rising temperatures in the Arctic cause accelerated mass loss from the Greenland Ice Sheet and reduced sea ice cover. Tidewater outlet glaciers represent direct connections between glaciers and the ocean where melt rates at the ice-ocean interface are influenced by ocean temperature and circulation. However, few measurements exist near outlet glaciers from the northern coast towards the Arctic Ocean that has remained nearly permanently ice covered. Here we present hydrographic measurements along the terminus of a major retreating tidewater outlet glacier from Flade Isblink Ice Cap. We show that the region is characterized by a relatively large change of the seasonal freshwater content, corresponding to ~2 m of freshwater, and that solar heating during the short open water period results in surface layer temperatures above 1 °C. Observations of temperature and salinity supported that the outlet glacier is a floating ice shelf with near-glacial subsurface temperatures at the freezing point. Melting from the surface layer significantly influenced the ice foot morphology of the glacier terminus. Hence, melting of the tidewater outlet glacier was found to be critically dependent on the retreat of sea ice adjacent to the terminus and the duration of open water.