Spreading of Greenland meltwaters in the ocean revealed by noble gases
Date
2015-09-30Metadata
Show full item recordCitable URI
https://hdl.handle.net/1912/7631As published
https://doi.org/10.1002/2015GL065003DOI
10.1002/2015GL065003Keyword
Glacial melt; Noble gases; Tracers; Meltwater; Greenland; FjordAbstract
We present the first noble gas observations in a proglacial fjord in Greenland, providing an unprecedented view of surface and submarine melt pathways into the ocean. Using Optimum Multiparameter Analysis, noble gas concentrations remove large uncertainties inherent in previous studies of meltwater in Greenland fjords. We find glacially modified waters with submarine melt concentrations up to 0.66 ± 0.09% and runoff 3.9 ± 0.29%. Radiogenic enrichment of Helium enables identification of ice sheet near-bed melt (0.48 ± 0.08%). We identify distinct regions of meltwater export reflecting heterogeneous melt processes: a surface layer of both runoff and submarine melt and an intermediate layer composed primarily of submarine melt. Intermediate ocean waters carry the majority of heat to the fjords' glaciers, and warmer deep waters are isolated from the ice edge. The average entrainment ratio implies that ocean water masses are upwelled at a rate 30 times the combined glacial meltwater volume flux.
Description
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): 7705–7713, doi:10.1002/2015GL065003.
Suggested Citation
Geophysical Research Letters 42 (2015): 7705–7713Related items
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