Spreading of Greenland meltwaters in the ocean revealed by noble gases
MetadataShow full item record
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.
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.
Showing items related by title, author, creator and subject.
Niu, Yi; Castro, M. Clara; Aciego, Sarah M.; Hall, Chris M.; Stevenson, Emily I.; Arendt, Carli A.; Das, Sarah B. (John Wiley & Sons, 2015-11-06)This study represents the first comprehensive noble gas study in glacial meltwater from the Greenland Ice Sheet. It shows that most samples are in disequilibrium with surface collection conditions. A preliminary Ne and Xe ...
Iceberg meltwater fluxes dominate the freshwater budget in Greenland's iceberg-congested glacial fjords Enderlin, Ellyn; Hamilton, Gordon S.; Straneo, Fiamma; Sutherland, David A. (John Wiley & Sons, 2016-11-09)Freshwater fluxes from the Greenland ice sheet have increased over the last two decades due to increases in liquid (i.e., surface and submarine meltwater) and solid ice (i.e., iceberg) fluxes. To predict potential ice ...
Stanford, Jennifer D.; Rohling, Eelco J.; Hunter, Sally E.; Roberts, Andrew P.; Rasmussen, Sune O.; Bard, Edouard; McManus, Jerry F.; Fairbanks, Richard G. (American Geophysical Union, 2006-12-09)The temporal relationship between meltwater pulse 1a (mwp-1a) and the climate history of the last deglaciation remains a subject of debate. By combining the Greenland Ice Core Project δ 18O ice core record on the new ...