UK-OSNAP-Decade: 10 years of observing and understanding the overturning circulation in the subpolar North Atlantic (2014-2024)
Lead Research Organisation:
National Oceanography Centre
Department Name: Science and Technology
Abstract
There is mounting evidence from measurements and models of the importance of the transports of heat and freshwater by the Subpolar North Atlantic Ocean. They impact on North Atlantic, European and global climate via temperature, precipitation and wind strength, and also on marine ecosystems, hurricanes, even rainfall in the Sahel, the Amazon and parts of the US. The subpolar North Atlantic behaves substantially differently from the subtropical North Atlantic circulation, and their mechanisms and timescales for transport and storage of heat and freshwater are very different. Prior to 2014 the subpolar North Atlantic was inadequately measured, and it is still the case that no ocean general circulation or climate model represents it accurately.
UK-OSNAP-Decade aims to generate new knowledge and understanding of the subpolar North Atlantic to improve predictions of the contribution of the region to climate, by building on the successes of NERC Large Grant UK OSNAP, and as a contribution to the international collaborative project OSNAP (Overturning in the Subpolar North Atlantic Programme). We propose a programme of sustained observation of subpolar North Atlantic circulation and fluxes; a UK contribution to an international trans-basin, full-depth ocean observation array.
UK-OSNAP-Decade aims to generate new knowledge and understanding of the subpolar North Atlantic to improve predictions of the contribution of the region to climate, by building on the successes of NERC Large Grant UK OSNAP, and as a contribution to the international collaborative project OSNAP (Overturning in the Subpolar North Atlantic Programme). We propose a programme of sustained observation of subpolar North Atlantic circulation and fluxes; a UK contribution to an international trans-basin, full-depth ocean observation array.
Planned Impact
The UK-OSNAP-Decade data and results will benefit the National Capability programme CLASS (Climate Linked Atlantic Sector Science) by providing additional information about the warm water pathways in the eastern subpolar North Atlantic, including their heat and salt transport and water mass transformation.
The results from OSNAP will feed into national and international climate assessments including the UK Marine Climate Change Impacts Partnership (MCCIP), the International Council for the Exploration of the Seas (ICES) Annual Report on Ocean Climate, and of course the Intergovernmental Panel for Climate Change (IPCC) Assessment Reports.
The results will underpin EU FP7 programmes including Blue-Action, Atlas and iAtlantic, and contribute to the Global Ocean Observing System (GOOS) as an OceanSites observatory. It is also a contribution to an all-Atlantic observing system.
The results from OSNAP will feed into national and international climate assessments including the UK Marine Climate Change Impacts Partnership (MCCIP), the International Council for the Exploration of the Seas (ICES) Annual Report on Ocean Climate, and of course the Intergovernmental Panel for Climate Change (IPCC) Assessment Reports.
The results will underpin EU FP7 programmes including Blue-Action, Atlas and iAtlantic, and contribute to the Global Ocean Observing System (GOOS) as an OceanSites observatory. It is also a contribution to an all-Atlantic observing system.
Publications
Benetti M
(2019)
Sources and Distribution of Fresh Water Around Cape Farewell in 2014
in Journal of Geophysical Research: Oceans
Berx B
(2021)
Climate-Relevant Ocean Transport Measurements in the Atlantic and Arctic Oceans
in Oceanography
Chafik L
(2022)
Rapid Communication of Upper-Ocean Salinity Anomaly to Deep Waters of the Iceland Basin Indicates an AMOC Short-Cut
in Geophysical Research Letters
Chafik L
(2023)
Observed mechanisms activating the recent subpolar North Atlantic Warming since 2016
in Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
Comer, E.A.
(2019)
Mean Transport and variability in the subpolar North Atlantic
Desbruyères D
(2020)
Importance of Boundary Processes for Heat Uptake in the Subpolar North Atlantic
in Journal of Geophysical Research: Oceans
Desbruyères D
(2021)
A shift in the ocean circulation has warmed the subpolar North Atlantic Ocean since 2016
in Communications Earth & Environment
Frajka-Williams E
(2019)
Atlantic Meridional Overturning Circulation: Observed Transport and Variability
in Frontiers in Marine Science
Fraser N
(2022)
North Atlantic Current and European Slope Current Circulation in the Rockall Trough Observed Using Moorings and Gliders
in Journal of Geophysical Research: Oceans
Fraser N
(2021)
120 Years of AMOC Variability Reconstructed From Observations Using the Bernoulli Inverse
in Geophysical Research Letters
González-Pola C
(2019)
The ICES Working Group on Oceanic Hydrography: A Bridge From In-situ Sampling to the Remote Autonomous Observation Era
in Frontiers in Marine Science
Gould W
(2021)
Global-scale patterns of observed sea surface salinity intensified since the 1870s
in Communications Earth & Environment
Hirschi J
(2019)
Insights into Decadal North Atlantic Sea Surface Temperature and Ocean Heat Content Variability from an Eddy-Permitting Coupled Climate Model
in Journal of Climate
Holliday N
(2020)
Ocean circulation causes the largest freshening event for 120 years in eastern subpolar North Atlantic
in Nature Communications
Hopkins J
(2019)
Transport Variability of the Irminger Sea Deep Western Boundary Current From a Mooring Array
in Journal of Geophysical Research: Oceans
Houpert L
(2020)
Observed Variability of the North Atlantic Current in the Rockall Trough From 4 Years of Mooring Measurements
in Journal of Geophysical Research: Oceans
Huthnance J
(2020)
Oceanic Density/Pressure Gradients and Slope Currents
in Journal of Physical Oceanography
Johnson C
(2020)
Significance of Climate Indices to Benthic Conditions Across the Northern North Atlantic and Adjacent Shelf Seas
in Frontiers in Marine Science
Kostov Y
(2021)
Distinct sources of interannual subtropical and subpolar Atlantic overturning variability
in Nature Geoscience
Le Bras I
(2021)
How Much Arctic Fresh Water Participates in the Subpolar Overturning Circulation?
in Journal of Physical Oceanography
Le Bras I
(2022)
Slantwise Convection in the Irminger Sea
in Journal of Geophysical Research: Oceans
Le Bras I
(2020)
Rapid Export of Waters Formed by Convection Near the Irminger Sea's Western Boundary
in Geophysical Research Letters
Li F
(2021)
Subpolar North Atlantic western boundary density anomalies and the Meridional Overturning Circulation.
in Nature communications
Li F
(2022)
Author Correction: Subpolar North Atlantic western boundary density anomalies and the Meridional Overturning Circulation.
in Nature communications
Li F
(2021)
Observation-based estimates of heat and freshwater exchanges from the subtropical North Atlantic to the Arctic
in Progress in Oceanography
Lozier MS
(2019)
A sea change in our view of overturning in the subpolar North Atlantic.
in Science (New York, N.Y.)
MacGilchrist G
(2021)
Demons in the North Atlantic: Variability of Deep Ocean Ventilation
in Geophysical Research Letters
Mackay N
(2020)
The Observation-Based Application of a Regional Thermohaline Inverse Method to Diagnose the Formation and Transformation of Water Masses North of the OSNAP Array from 2013 to 2015
in Journal of Physical Oceanography
Pacini A
(2021)
Cyclonic eddies in the West Greenland Boundary Current System
in Journal of Physical Oceanography
Petit T
(2020)
Atlantic Deep Water Formation Occurs Primarily in the Iceland Basin and Irminger Sea by Local Buoyancy Forcing
in Geophysical Research Letters
Rossby T
(2020)
What can Hydrography Tell Us About the Strength of the Nordic Seas MOC Over the Last 70 to 100 Years?
in Geophysical Research Letters
Roussenov V
(2022)
Historical Reconstruction of Subpolar North Atlantic Overturning and Its Relationship to Density
in Journal of Geophysical Research: Oceans
Zhang R
(2019)
Local and Downstream Relationships between Labrador Sea Water Volume and North Atlantic Meridional Overturning Circulation Variability
in Journal of Climate
Zou S
(2021)
Observed Deep Cyclonic Eddies around Southern Greenland
in Journal of Physical Oceanography
| Description | OSNAP operates an observing system in the subpolar North Atlantic (the ocean between Canada, Greenland, Iceland and the UK) that has caused a step change in our understanding of the nature of the large scale ocean circulation and what causes it to change over time. The new OSNAP insight has caused scientists to reconsider how effective ocean and climate models are at reproducing the real ocean processes in this region, leading to improvements in the models. This is necessary in order for us to have robust projections of future climate. The system of ocean currents that OSNAP is working to understand is called the Meridional Overturning Circulation, and is predicted to decline as a result of climate change, leading to changes in sea level, hurricanes, rainfall over the Sahel, and extreme weather over the UK. |
| Exploitation Route | The outcomes feed into synthesis and review reports including the Intergovernmental Panel on Climate Change, and the UK's Marine Climate Change Impact Partnership reports. |
| Sectors | Agriculture, Food and Drink,Education,Energy,Environment,Financial Services, and Management Consultancy,Leisure Activities, including Sports, Recreation and Tourism,Government, Democracy and Justice |
| URL | https://www.ukosnap.org/ |
| Description | In the IPCC AR5 report and special report on the ocean and cryosphere, the outputs from OSNAP have been used to evaluate the present state of knowledge of North Atlantic Ocean circulation. New reports from the UK Marine Climate Change Impacts Partnership have included information from OSNAP. |
| First Year Of Impact | 2021 |
| Sector | Environment,Government, Democracy and Justice |
| Impact Types | Policy & public services |