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


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.

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.


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Related Projects

Project Reference Relationship Related To Start End Award Value
NE/T00858X/1 30/06/2019 31/10/2019 £882,356
NE/T00858X/2 Transfer NE/T00858X/1 01/11/2019 29/06/2023 £801,518
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

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.
First Year Of Impact 2021
Sector Environment,Government, Democracy and Justice
Impact Types Policy & public services