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Oceanic heat delivery via Kangerdlugssuaq Fjord to the south‐east Greenland ice sheet
Author(s) -
Inall Mark E.,
Murray Tavi,
Cottier Finlo R.,
Scharrer Kilian,
Boyd Timothy J.,
Heywood Karen J.,
Bevan Suzanne L.
Publication year - 2014
Publication title -
journal of geophysical research: oceans
Language(s) - English
Resource type - Journals
eISSN - 2169-9291
pISSN - 2169-9275
DOI - 10.1002/2013jc009295
Subject(s) - greenland ice sheet , fjord , geology , oceanography , glacier , ice sheet , future sea level , water mass , cryosphere , climatology , iceberg , arctic ice pack , ice stream , sea ice , geomorphology
Acceleration of the Greenland Ice Sheet (GrIS) tidewater outlet glaciers has increased the ice sheet's contribution to global sea level rise over the last two decades. Coincident increases in atmospheric temperatures around Greenland explain some of the increased ice loss, but warm Atlantic‐origin water (AW) is increasingly recognized as contributing to the accelerating ice‐mass loss, particularly, via the outlet glaciers of south‐east (SE) Greenland. However, there remains a lack of understanding of the variability in heat content of the water masses found to the east of Greenland and how this heat is communicated to the outlet glaciers of the GrIS. Here a new analysis is presented of ocean/GrIS interaction in which the oceanic heat flux toward the ice sheet in Kangerdlugssuaq Fjord (0.26 TW) is an order‐of‐magnitude greater than that reported for the other major outlet glacier of SE Greenland (Helheim). Heat delivered by AW to the calving front of Kangerdlugssuaq is equivalent to ∼10 m d −1 melt (i.e., 30–60% of the ice flow speed), and thus is highly significant. During the observational campaign in September 2010 warm Polar Surface Water (PSWw) melted a substantial volume of ice within the fjord; equivalent to 25% of the volume melted by AW alone. Satellite‐derived sea surface temperatures show large interannual variability in PSWw over the 20 year period 1991–2011. Anomalously warm PSWw was observed within the fjord prior to the well‐documented major ice front retreats of May 2004 and November 2010.