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Details of Award

NERC Reference : NE/P020755/1

Calibrated pCO2 in air and surface ocean Sensor for ASVs (CaPASOS)

Grant Award

Principal Investigator:
Professor A Watson, University of Exeter, Geography
Co-Investigator:
Professor JR Fishwick, Plymouth Marine Laboratory, Plymouth Marine Lab
Co-Investigator:
Dr U Schuster, University of Exeter, Geography
Science Area:
Atmospheric
Freshwater
Marine
Overall Classification:
Unknown
ENRIs:
Biodiversity
Environmental Risks and Hazards
Global Change
Natural Resource Management
Pollution and Waste
Science Topics:
Carbon cycling
Ocean acidification
Biogeochemical Cycles
Carbon cycle
Gas exchange
Greenhouse gases
Ocean - Atmosphere Interact.
Biogeochemical Cycles
Ocean acidification
Oceanography
Earth & environmental
Limnology
Climate & Climate Change
Ocean acidification
Ocean atmosphere interaction
Abstract:
The human emission of carbon dioxide, largely from fossil fuel burning, will continue for the foreseeable future to be the most important cause of climate change. Only about half of our emissions are remaining in the atmosphere however. The other half is being absorbed, it is believed, in approximately equal amounts by vegetation on land and uptake by the ocean. These "natural sinks" of CO2 are consequently of huge value to us, since they slow the progress of climate change, so their present operation, and possible changes future uptake of CO2, are a focus of intense research. The sink of CO2 into the ocean is today being observed by measurements of atmospheric and sea surface pCO2, the partial pressure of CO2 at the surface of the ocean. This controls the rate at which CO2 exchanges between the ocean and atmosphere, and which for this reason has been designated an "essential ocean variable" by the Global Ocean Observing System. These observations are usually made from commercial vessels, and where there are busy shipping routes, for example in much of the Atlantic and North Pacific Oceans, there are sufficient observations to describe the air-sea flux. However, there are other very large regions (the Indian, South Pacific and Southern Oceans for example) where we have woefully insufficient data. In the future, this need could be met by autonomous surface vehicles (ASVs) making pCO2 measurements, and our proposal is to develop a pCO2 sensor specifically designed for ASVs. It will follow protocols that have been established by international bodies for the highest quality measurements suited to calculating the air-sea flux of carbon dioxide in the open ocean. The technical challenge is to adapt the successful principles of the instruments mounted in ships or on large buoys, where space and power are not limiting factors, to achieve the same high accuracy with small space and power footprint, resistance to violent motion, and long endurance, necessary on an ASV. We will achieve this by bringing together the extensive experience that the Exeter University group has in operating ship-based CO2 systems over 20 years, with improvements in engineering, utilising the experience and expertise of the NOC Technology and Engineering groups. We will use the basic measurement technique that has been well tested on the large instruments (equiibration of water with gas, and measurement of CO2 in gas by non-dispersive infra-red detection). However, we will use miniaturised components having small volumes and low flow rates of gas, enabling even a small instrument to carry on-board calibration gases. The specifications of the final instrument will include: endurance of up to a year and with frequency of measurements (both surface water and atmosphere) sufficient to define daily cycles, regular calibration using on-board calibration gases stored in miniature compressed gas cylinders, and measurement of CO2 in dried air which has equilibrated with surface water by direct contact. The instrument will also conform to data standards and integration protocols to enable the ready integration and exchange of sensors into autonomous platforms. A laboratory prototype exists, built by U. Exeter. To achieve our main objective, our sub-objectives are: 1) Development of second generation and deployment alongside a shipboard instrument and testing at coastal sites (2) modification and deployment on a mooring at the Western Channel Observatory for an extended period (3) Construction of third generation with attention to each component of the system to optimise performance and robustness, (4) integration into an ASV, (5) extensive sea testing (e.g. on the "MASSMO" exercises, experimental missions of autonomous marine vehicles conducted regularly around UK waters, and on research cruises.
Period of Award:
1 Jul 2017 - 1 Jul 2017
Value:
£425,507 Lead Split Award
Authorised funds only
NERC Reference:
NE/P020755/1
Grant Stage:
Awaiting Termination
Scheme:
Directed (RP) - NR1
Grant Status:
Closed

This grant award has a total value of £425,507  

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FDAB - Financial Details (Award breakdown by headings)

DI - Other CostsIndirect - Indirect CostsDA - InvestigatorsDA - Estate CostsDI - StaffDA - Other Directly AllocatedDI - T&S
£90,351£68,885£32,590£25,882£137,898£62,489£7,413

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