Water exchange between the continental shelf and the cavity beneath Nioghalvfjerdsbræ (79 North Glacier)
MetadataShow full item record
The mass loss at Nioghalvfjerdsbræ is primarily due to rapid submarine melting. Ocean data obtained from beneath the Nioghalvfjerdsbræ ice tongue show that melting is driven by the presence of warm (1°C) Atlantic Intermediate Water (AIW). A sill prevents AIW from entering the cavity from Dijmphna Sund, requiring that it flow into the cavity via bathymetric channels to the south at a pinned ice front. Comparison of water properties from the cavity, Dijmphna Sund, and the continental shelf support this conclusion. Overturning circulation rates inferred from observed melt rates and cavity stratification suggest an exchange flow between the cavity and the continental shelf of 38mSv, sufficient to flush cavity waters in under 1 year. These results place upper bounds on the timescales of external variability that can be transmitted to the glacier via the ice tongue cavity.
Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 42 (2015): 7648–7654, doi:10.1002/2015GL064944.
Showing items related by title, author, creator and subject.
The metabolic response of thecosome pteropods from the North Atlantic and North Pacific oceans to high CO2 and low O2 Maas, Amy E.; Lawson, Gareth L.; Wang, Zhaohui Aleck (Copernicus Publications on behalf of the European Geosciences Union, 2016-11-17)As anthropogenic activities directly and indirectly increase carbon dioxide (CO2) and decrease oxygen (O2) concentrations in the ocean system, it becomes important to understand how different populations of marine animals ...
The impact of the North Atlantic Oscillation on the uptake and accumulation of anthropogenic CO2 by North Atlantic Ocean mode waters Levine, Naomi M.; Doney, Scott C.; Lima, Ivan D.; Wanninkhof, Rik; Bates, Nicholas R.; Feely, Richard A. (American Geophysical Union, 2011-09-21)The North Atlantic Ocean accounts for about 25% of the global oceanic anthropogenic carbon sink. This basin experiences significant interannual variability primarily driven by the North Atlantic Oscillation (NAO). A suite ...
Keigwin, Lloyd D.; Cook, Mea S. (American Geophysical Union, 2007-07-11)A simple ocean/atmosphere feedback may reduce the amplitude of climate variability in around the North Atlantic during interglacial compared to glacial states. When climate is warm in the North Atlantic region, the ...