Greenland freshwater pathways in the sub-Arctic Seas from model experiments with passive tracers
Dukhovskoy, Dmitry S.
Myers, Paul G.
Platov, Gennady A.
Bamber, Jonathan L.
Chassignet, Eric P.
Lee, Craig M.
MetadataShow full item record
KeywordGreenland Ice Sheet melting; Greenland freshwater; Thermohaline circulation; Nordic Seas; Sub-Arctic seas; Baffin Bay; Labrador Sea
Accelerating since the early 1990s, the Greenland Ice Sheet mass loss exerts a significant impact on thermohaline processes in the sub-Arctic seas. Surplus freshwater discharge from Greenland since the 1990s, comparable in volume to the amount of freshwater present during the Great Salinity Anomaly events, could spread and accumulate in the sub-Arctic seas, influencing convective processes there. However, hydrographic observations in the Labrador Sea and the Nordic Seas, where the Greenland freshening signal might be expected to propagate, do not show a persistent freshening in the upper ocean during last two decades. This raises the question of where the surplus Greenland freshwater has propagated. In order to investigate the fate, pathways, and propagation rate of Greenland meltwater in the sub-Arctic seas, several numerical experiments using a passive tracer to track the spreading of Greenland freshwater have been conducted as a part of the Forum for Arctic Ocean Modeling and Observational Synthesis effort. The models show that Greenland freshwater propagates and accumulates in the sub-Arctic seas, although the models disagree on the amount of tracer propagation into the convective regions. Results highlight the differences in simulated physical mechanisms at play in different models and underscore the continued importance of intercomparison studies. It is estimated that surplus Greenland freshwater flux should have caused a salinity decrease by 0.06–0.08 in the sub-Arctic seas in contradiction with the recently observed salinification (by 0.15–0.2) in the region. It is surmised that the increasing salinity of Atlantic Water has obscured the freshening signal.
Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 121 (2016): 877–907, doi:10.1002/2015JC011290.
Suggested CitationArticle: Dukhovskoy, Dmitry S., Myers, Paul G., Platov, Gennady A., Timmermans, Mary-Louise, Curry, Beth, Proshutinsky, Andrey, Bamber, Jonathan L., Chassignet, Eric P., Hu, Xianmin, Lee, Craig M., Somavilla, Raquel, "Greenland freshwater pathways in the sub-Arctic Seas from model experiments with passive tracers", Journal of Geophysical Research: Oceans 121 (2016): 877–907, DOI:10.1002/2015JC011290, https://hdl.handle.net/1912/7922
Showing items related by title, author, creator and subject.
Peterson, Bruce J.; McClelland, James W.; Curry, Ruth G.; Holmes, Robert M.; Walsh, John E.; Aagaard, Knut (2006-06-22)Manifold changes in the freshwater cycle of high-latitude lands and oceans have been reported in the past few years. A synthesis of these changes in sources of freshwater and in ocean freshwater storage illustrates the ...
Sutherland, David A.; Pickart, Robert S.; Jones, E. Peter; Azetsu-Scott, Kumiko; Eert, A. Jane; Olafsson, Jon (American Geophysical Union, 2009-05-27)The freshwater composition of waters on the southeast Greenland shelf and slope are described using a set of high-resolution transects occupied in summer 2004, which included hydrographic, velocity, nutrient, and chemical ...
Yang, Jiayan (American Meteorological Society, 2005-12)According to observations, the Arctic Ocean circulation beneath a shallow thermocline can be schematized by cyclonic rim currents along shelves and over ridges. In each deep basin, the circulation is also believed to be ...