Characteristics, recent evolution, and ongoing retreat of Hunt Fjord Ice Shelf, northern Greenland

• Published in: Journal of Glaciology
• Main Authors: Ochwat, Naomi, Scambos, Ted, Fahnestock, Mark, Stammerjohn, Sharon
• Other Authors: U.S. Geological Survey
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2022
• Subjects: Arctic; Greenland; Hunt Fjord; glacier; Ice Sheet; Ice Shelf; Ice Shelves; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/jog.2022.44; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143022000442

Abstract Arctic ice shelves have declined over the past several decades, one of many indications of a rapidly changing cryosphere. Here we use a collection of off-nadir Landsat 8 images, a 1978 digital orthophotograph and photogrammetrically derived DEM, satellite altimetry and other data to examine the causes of an Arctic ice-shelf retreat in northernmost Greenland, the Hunt Fjord Ice Shelf (HFIS). HFIS has several distinct provenance regions comprised of glacier-derived ice and corrugated multi-decadal fast ice, with varying ice thicknesses (5–64 m). Available imagery shows little change in HFIS between 1978 and 2012, after which several midsummer calving events occurred (2012, 2016 and 2019) that reduced the HFIS by 42.5 km 2 (~56%). Shelf area losses began as the number of surface melt days on the adjacent ice sheet more than doubled relative to the 1980s. Recent calving events also occurred during open-water periods at the ice-shelf front. Prior to mid-2012, there were no calving events during similar open-water periods. HFIS tributary glaciers have thinned by 3–20 m near their grounding zones, and may have accelerated since the 1980s, likely due to increased basal melting from contact with warm Atlantic Water.