A sea change in our view of overturning in the subpolar North Atlantic

2019/02/01 by M. Susan Lozier, Feili Li, Sheldon Bacon +35 · 1 citation
Earth and Planetary Sciences · #Oceanographic and Atmospheric Processes #Arctic and Antarctic ice dynamics #Geology and Paleoclimatology Research

paper · pdf · doi:10.1126/science.aau6592

openalex publication_date 2019/02/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/03

Abstract

To provide an observational basis for the Intergovernmental Panel on Climate Change projections of a slowing Atlantic meridional overturning circulation (MOC) in the 21st century, the Overturning in the Subpolar North Atlantic Program (OSNAP) observing system was launched in the summer of 2014. The first 21-month record reveals a highly variable overturning circulation responsible for the majority of the heat and freshwater transport across the OSNAP line. In a departure from the prevailing view that changes in deep water formation in the Labrador Sea dominate MOC variability, these results suggest that the conversion of warm, salty, shallow Atlantic waters into colder, fresher, deep waters that move southward in the Irminger and Iceland basins is largely responsible for overturning and its variability in the subpolar basin.

Citations

• Observing the Atlantic Meridional Overturning Circulation yields a decade of inevitable surprises
• Decadal variability of subpolar gyre transport and its reverberation in the North Atlantic overturning
• Temporal Variability of the Atlantic Meridional Overturning Circulation at 26.5°N
• The ERA‐Interim reanalysis: configuration and performance of the data assimilation system
• Further intensification of deep convection in the Labrador Sea in 2016
• Seasonal Overturning of the Labrador Sea as Observed by Argo Floats
• Increases in the Pacific inflow to the Arctic from 1990 to 2015, and insights into seasonal trends and driving mechanisms from year-round Bering Strait mooring data
• Climate Change on Newfoundland and Labrador Shelves: Results From a Regional Downscaled Ocean and Sea-Ice Model Under an A1B Forcing Scenario 2011–2069
• The North Atlantic Ocean Is in a State of Reduced Overturning
• Anomalously weak Labrador Sea convection and Atlantic overturning during the past 150 years

Cited by

• Atlantic meridional overturning circulation [wikipedia]