A possible effect of a carbon dioxide leak from an industrial sub-sea floor storage facility, utilised for Carbon Capture and Storage, is that escaping carbon dioxide gas will dissolve in sediment pore waters and reduce their pH. To quantify the scale and duration of such an impact, a novel, field scale experiment was conducted, whereby carbon dioxide gas was injected into unconsolidated sub-sea floor sediments for a sustained period of 37 days. During this time pore water pH in shallow sediment (5 mm depth) above the leak dropped >0.8 unit, relative to a reference zone that was unaffected by the carbon dioxide. After the gas release was stopped, the pore water pH returned to normal background values within a three-week recovery period. Further, the total mass of carbon dioxide dissolved within the sediment pore fluids above the release zone was modelled by the difference in DIC between the reference and release zones. Results showed that between 14 and 63% of the carbon dioxide released during the experiment could remain in the dissolved phase within the sediment pore water. This is a publication in QICS Special Issue - International Journal of Greenhouse Gas Control, Peter Taylor et. al. Doi:10.1016/j.ijggc.2014.09.006.
Carbon capture and storage is a mitigation strategy that can be used to aid the reduction of anthropogenic CO2 emissions. This process aims to capture CO2 from large point-source emitters and transport it to a long-term storage site. For much of Europe, these deep storage sites are anticipated to be sited below the sea bed on continental shelves. A key operational requirement is an understanding of best practice of monitoring for potential leakage and of the environmental impact that could result from a diffusive leak from a storage complex. Here we describe a controlled CO2 release experiment beneath the seabed, which overcomes the limitations of laboratory simulations and natural analogues. The complex processes involved in setting up the experimental facility and ensuring its successful operation are discussed, including site selection, permissions, communications and facility construction. The experimental design and observational strategy are reviewed with respect to scientific outcomes along with lessons learnt in order to facilitate any similar future. This is a publication in QICS Special Issue - International Journal of Greenhouse Gas Control, Peter Taylor et. al. Doi:10.1016/j.ijggc.2014.09.007.
Carbon capture and storage (CCS) is a way of possibly reducing impacts from fossil fuel emissions by injecting large volumes of carbon dioxide into appropriate geological formations. Some of the existing and proposed storage sites are below the seabed. In order to better understand the environmental impacts of leaks from a sub-surface marine storage facility and to investigate how leaks or potential leaks could be detected, a world-first experiment consisting of an artificial carbon dioxide release from below the seabed was undertaken in 2012. The need for accurate deployments and re-deployments of measurement equipment, the retrieval of biological and sediment samples within very specific areas of the release site and the in-situ measurement of escaping gas volumes, necessitated an extensive scientific diving program. Diving was also employed to determine the most optimum experimental site prior to the program’s initiation and to map the site prior to the beginning of the experiment. Diving also proved to be an essential tool (through observation, photography and videography) in recording the progress of the experiment and the physical interactions and impacts arising from managing a large multi-partner, multi-discipline research program. This is a publication in Diving for Science 2014: Proceedings of the American Academy for Underwater Sciences 33rd Symposium, Martin D.J. Sayer et. al. http://www.aaus.org/uploads/protected/files/publications/symposium_proceedings/diving_for_science_2014.pdf
A two-fluid, small scale numerical ocean model was developed to simulate plume dynamics and increases in water acidity due to leakages of CO2 from potential sub-seabed reservoirs erupting, or pipeline breaching into the North Sea. The location of a leak of such magnitude is unpredictable; therefore, multiple scenarios are modelled with the physiochemical impact measured in terms of the movement and dissolution of the leaked CO2. A correlation for the drag coefficient of bubbles/droplets free rising in seawater is presented and a sub-model to predict the initial bubble/droplet size forming on the seafloor is proposed. With the case studies investigated, the leaked bubbles/droplets fully dissolve before reaching the water surface, where the solution will be dispersed into the larger scale ocean waters. The tools developed can be extended to various locations to model the sudden eruption, which is vital in determining the fate of the CO2 within the local waters. This is a publication in Marine Pollution Bulletin, Marius Dewar et. al. doi:10.1016/j.marpolbul.2013.03.005.
The dataset details global positioning system (GPS) locations recorded for survey quadrats at six UK saltmarsh sites. Three of the sites were in Morecambe Bay, North West England and three of the sites were in Essex, South East England, each of these sites consisted of a salt marsh area and adjacent mudflat area. Each site comprised 22 quadrats on the unvegetated mudflat and 22 quadrats on the salt marsh. The locations indicated by this dataset correspond to the south-east corner of the quadrats which were 1m square and oriented with their sides aligned North-South and East-West. We combined spatial data relating to the environs of the study sites from a number of sources (Ordnance Survey Digital Terrain Models, Ordnance Survey Boundary Line, Environment Agency Saltmarsh Extents, Natural England Priority Habitat Inventory). These were rasterised and quadrat values were extracted on a pointwise basis for elevation and proximity (distance to creek, habitat edge and high water mark). Tidal height was calculated with reference to the relevant Tidal Gauge and Admiralty Standard Port information. This data was derived as part of Coastal Biodiversity and Ecosystem Service Sustainability (CBESS): NE/J015644/1. The project was funded with support from the Biodiversity and Ecosystem Service Sustainability (BESS) programme. BESS is a six-year programme (2011-2017) funded by the UK Natural Environment Research Council (NERC) and the Biotechnology and Biological Sciences Research Council (BBSRC) as part of the UK's Living with Environmental Change (LWEC) programme. Full details about this dataset can be found at https://doi.org/10.5285/78a2cab5-dca5-411b-ac5b-c2c080928b1d
The dataset comprises 75 hydrographic data profiles, collected by a conductivity-temperature-depth (CTD) sensor package, from across the Norwegian Sea area specifically along and across the West Spitsbergen Shelf during August and September 2005. A complete list of all data parameters are described by the SeaDataNet Parameter Discovery Vocabulary (PDV) keywords assigned in this metadata record. The data were collected by the Scottish Association for Marine Science as part of the Northern Seas Programme (NSP).
The dataset comprises 115 hydrographic data profiles, collected by a conductivity-temperature-depth (CTD) sensor package, from across the North Sea area specifically at the JONSIS standard section in the northern North Sea, the standard Faroe Shetland Channel sections, across the Anton Dohrn Seamount and in the Wyville-Thomson Ridge area. Data collected during April and May of 2006. A complete list of all data parameters are described by the SeaDataNet Parameter Discovery Vocabulary (PDV) keywords assigned in this metadata record. The data were collected by the Fisheries Research Services Aberdeen Marine Laboratory.
The dataset comprises 113 hydrographic data profiles, collected by a conductivity-temperature-depth (CTD) sensor package, from the North Sea and North East Atlantic Ocean (limit 40W) area including specific locations: the JONSIS standard section in the northern North Sea; the standard Faroe Shetland Channel sections; the standard Rockall section; and the area north east of Rockall up to the Wyville - Thomson Ridge area. Measurements taken during September 2003. A complete list of all data parameters are described by the SeaDataNet Parameter Discovery Vocabulary (PDV) keywords assigned in this metadata record. The data were collected by the Fisheries Research Services Aberdeen Marine Laboratory.
The dataset comprises 44 hydrographic data profiles, collected by a conductivity-temperature-depth (CTD) sensor package, during January - February 2000 along the Ellett Line between Scotland and Rockall. A complete list of all data parameters are described by the SeaDataNet Parameter Discovery Vocabulary (PDV) keywords assigned in this metadata record. The data were collected by the Scottish Association for Marine Science.
This dataset consists of current velocity measurements of the water column from an upward-looking Acoustic Doppler Current Profiler (ADCP) deployed on the seabed and also includes CTD casts from an SBE 911+ CTD taken a long the Wyville Thompson Ridge. The mooring is situated in the region of the Wyville Thomson Ridge – a notable bathymetric feature running north-west from the Scottish shelf towards the Faroe Bank. The gully present between the Ridge and the parallel Ymir Ridge is the study site chosen for mooring work that began in 2003 and ended in 2013. Mooring deployment durations have typically ranged from between five and twelve months. Successive deployments have enabled a multi-year time series to develop. There have, however, been periods of instrumentation loss, which account for some gaps in the overall record (most noticeably during 2008/2009). Servicing of the mooring has been achieved using various research vessels and has often been incorporated into the schedule of the annual cruises occupying the Extended Ellett Line. The mooring consists of an anchored buoy housing an RDI Long Ranger ADCP, designed to rest on the seabed, with the instrument facing upwards. Current velocity measurements from the mooring help to provide valuable insight into regional ocean circulation. A small, poorly quantified, component of the southward-flowing deep water from the Arctic cascades over the Wyville Thomson Ridge from the Faroe Bank Channel into the northern Rockall Trough. Maintaining this time series will afford a better understanding of this outflow. The Wyville Thomson mooring work is led by Toby Sherwin at the Scottish Association for Marine Science (SAMS).