Assessing the role of eddies in exchanging nutrients across the European Shelf
Lead Research Organisation:
University of Liverpool
Department Name: Earth, Ocean and Ecological Sciences
Abstract
The ocean is full of time-varying, swirling circulations, called eddies. These eddies transfer heat, nutrients and carbon from one region to another, affecting the local store of each of these properties. This eddy exchange potentially becomes important across strong flows, such as boundary currents, jets and slope currents. However, while eddies are seen to occur throughout the ocean (such as remotely sensed observations), there have been very few systematic, repeated observations revealing how eddies transfer properties in the horizontal, particularly below the surface. Instead we have to rely on a combination of model and theoretical studies to understand the role of eddies in the ocean, often drawing parallels with how weather systems behave in the atmosphere.
In this study, we wish to use the new glider technology to identify how eddies transfer nutrients in the horizontal. We wish to investigate this eddy transfer on the European Shelf at three different sites, drawing on the support of an existing programme, FASTNET, examining the physical exchange across the shelf break. Our aim is to include nutrient sensors in two gliders, one supported under FASTNET and the other supported via this call. Together with nutrient data from FASTNET cruises, we aim to use the glider data to estimate the eddy flux of nutrients in these three different sites between the open ocean and shelf seas. Our hypothesis is that the eddies provide a flux of inorganic nutrients from the open ocean to the shelf seas, across the shelf break, as well as a return flux of dissolved organic nutrients from the shelf seas to the open ocean.
The eddy fluxes of nutrients onto the shelf are potentially important in sustaining biological productivity, there are particularly high rates of photosynthesis here, sustaining fishing activity and providing a biological drawdown of atmospheric carbon dioxide.
In the longer term, the glider technology has the potential to provide the repeated observations needed to quantify eddies fluxes throughout the ocean. This step is necessary to really understand how heat, nutrients and carbon are transferred throughout the ocean, as well as the wider goal of how the ocean operates in the climate system.
In this study, we wish to use the new glider technology to identify how eddies transfer nutrients in the horizontal. We wish to investigate this eddy transfer on the European Shelf at three different sites, drawing on the support of an existing programme, FASTNET, examining the physical exchange across the shelf break. Our aim is to include nutrient sensors in two gliders, one supported under FASTNET and the other supported via this call. Together with nutrient data from FASTNET cruises, we aim to use the glider data to estimate the eddy flux of nutrients in these three different sites between the open ocean and shelf seas. Our hypothesis is that the eddies provide a flux of inorganic nutrients from the open ocean to the shelf seas, across the shelf break, as well as a return flux of dissolved organic nutrients from the shelf seas to the open ocean.
The eddy fluxes of nutrients onto the shelf are potentially important in sustaining biological productivity, there are particularly high rates of photosynthesis here, sustaining fishing activity and providing a biological drawdown of atmospheric carbon dioxide.
In the longer term, the glider technology has the potential to provide the repeated observations needed to quantify eddies fluxes throughout the ocean. This step is necessary to really understand how heat, nutrients and carbon are transferred throughout the ocean, as well as the wider goal of how the ocean operates in the climate system.
Planned Impact
Impact summary is not required, as that component is provided by FASTNET.
Publications
Porter M
(2016)
Glider observations of enhanced deep water upwelling at a shelf break canyon: A mechanism for cross-slope carbon and nutrient exchange
in Journal of Geophysical Research: Oceans
Carr N
(2019)
Seasonal and spatial variability in the optical characteristics of DOM in a temperate shelf sea
in Progress in Oceanography
Description | Dissolved organic matter is exported from the Celtic Sea to the North Atlantic Ocean. |
Exploitation Route | Marine monitoring |
Sectors | Environment |
Description | An Alternative Framework to Assess Marine Ecosystem Functioning in Shelf Seas (AlterEco) |
Amount | £1,657,000 (GBP) |
Funding ID | NE/P013902/1 |
Organisation | Natural Environment Research Council |
Sector | Public |
Country | United Kingdom |
Start | 04/2017 |
End | 05/2020 |
Description | Collaboration with NOC scientists on gliders and oxygen |
Organisation | National Oceanography Centre |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Based on working with glider data, we developed ideas into a new NERC large grant called AlterEco which was funded in 2016 and led by Dr. Matthew Palmer tat NOC. |
Collaborator Contribution | Based on working with glider data, we developed ideas into a new NERC large grant called AlterEco which was funded in 2017 and led by Dr. Matthew Palmer tat NOC. |
Impact | Presentation at the ASLO Ocean Sciences meeting in 2018. |
Start Year | 2017 |