Recent Increases in Arctic Freshwater Flux Affects Labrador Sea Convection and Atlantic Overturning Circulation

Qian Yang, Tim Dixon, Paul G. Myers, Jennifer Bonin, Don Chambers, M.R. van den Broeke, Mads H. Ribergaard, John Mortensen

Research output: Contribution to journalArticlepeer-review

Abstract

The Atlantic Meridional Overturning Circulation (AMOC) is an important component of ocean thermohaline circulation. Melting of Greenland’s ice sheet is freshening the North Atlantic; however, whether the augmented freshwater flux is disrupting the AMOC is unclear. Dense Labrador Sea Water (LSW), formed by winter cooling of saline North Atlantic water and subsequent convection, is a key component of the deep southward return flow of the AMOC. Although LSW formation recently decreased, it also reached historically high values in the mid-1990s, making the connection to the freshwater flux unclear. Here we derive a new estimate of the recent freshwater flux from Greenland using updated GRACE satellite data, present new flux estimates for heat and salt from the North Atlantic into the Labrador Sea and explain recent variations in LSW formation. We suggest that changes in LSW can be directly linked to recent freshening, and suggest a possible link to AMOC weakening.

Original languageAmerican English
JournalNature Communications
Volume7
DOIs
StatePublished - Jan 1 2016

Keywords

  • Physical oceanography

Disciplines

  • Earth Sciences
  • Geology
  • Marine Biology

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