Development of a Three-Dimensional Hydrodynamic Model of Port Vila, Vanuatu, for Water Quality Assessment

Water Qualit

Assessment of nutrients and macroalgae growth in Poole Harbour, UK

Water Qualit

Modelling potential drivers of fish kill events in Sulaibikhat Bay, Kuwait

Water Qualit

Modelling the hydrodynamic and morphological impacts of a tidal stream development in Ramsey Sound

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordA number of sites around the UK are being considered for development of tidal stream energy, one of which is Ramsey Sound off the coast of Pembrokeshire, South Wales. The Sound was used to test the prototype of the Delta Stream by Tidal Energy Ltd. After initial testing, a 10 MW tidal array was proposed at St David’s Head. To investigate any possible environmental impacts of the array due to energy extraction, a case study of the Pembrokeshire coast was performed using a high-resolution depth averaged hydrodynamic model, Telemac2D, to investigate changes to hydrodynamics and morphodynamics. Results show that the proposed array of nine tidal energy converters will cause alterations to eddy propagation leading to changes in the velocity field up to 24km from the tidal array. Changes in morphodynamics are predicted through alterations to the bed shear stress. Changes to the mean and maximum bed shear stress, over a 30-day period, are found to be more localised and extend 12km from the array. These changes indicate that the proposed tidal array will lead to localised sediment accumulation and will act as a barrier to sediment transport, with potential consequences for the benthic ecology of the region.The authors thank Cardiff University for providing ADCP data through Ramsey Sound. The work was funded by the Industrial Doctorate Centre for Offshore Renewable Energy which is funded by the Energy Technologies Institute and the RCUK Energy Programme, grant number (EP/J500847/1). This work was carried out on the High Performance Computing Cluster supported by the Research and Specialist Computing Support service at the University of East Anglia

100% RAG: Syracuse School of Architecture, Student Newspaper, Volume 1, Number 1

100% RAG: Syracuse School of Architecture, Student Newspaper, Volume 1, Number 1. Student newsletter from student contributors of Syracuse School of Architecture in 1975

Numerical modelling of the interaction between tidal stream turbines and the benthic environment

The tidal stream industry has seen large growth in recent years, and the number of pre-commercial scale devices currently being tested reflects this development. However, commercialising this technology whilst showing that their environmental impacts is minimal remains a challenge. The impact on benthic communities is not considered to be a key strategic consenting issue, yet it is anticipated that the benthic habitat will change as a result of the presence of tidal turbines. To date, only single tidal turbine devices have been installed to demonstrate the application of tidal stream technology but despite successful tests there are still uncertainties surrounding the quantitative impacts these turbines have on local benthic communities. Unlike the wind industry, where physical effects of wind turbines have been catalogued through deployment of thousands of turbines, the tidal stream industry lacks these array scale quantitative data. Local impacts are known, but understanding the scale of the impacts and their relative significance of large arrays remains unknown. Tidal turbines (both single and arrays) interact with the hydrodynamics by decreasing the near field current flow directly in its wake through energy extraction and the drag caused by the physical structure. However, turbines may also affect the far field hydrodynamics, altering bed characteristics, sediment transport regimes and suspended sediment concentrations. As benthic habitats are closely linked to the physical seabed composition and the hydrodynamic conditions, the benthic environment is affected by to changes in the current flow. This thesis presents a series of studies investigating the interaction between tidal turbines and the benthic environment. Based on the hydrodynamic modelling software, TELEMAC2D, a numerical model has been developed to investigate the hydrodynamic impact of a single tidal array at Ramsey Sound, Pembrokeshire as well as the cumulative impact of multiple tidal developments in the Irish Sea. Based on the results of the models, the hydrodynamic outputs were used as inputs to drive a species distribution model, based on the software MaxEnt, to investigate how the distribution of benthic species altered in the presence of a 10MW tidal array at Ramsey Sound. Results of the study showed the development would have a minimal negative impact on the benthic environment

Cumulative impact assessment of tidal stream energy extraction in the Irish Sea

A cumulative impact assessment of tidal stream developments in the Irish Sea has been conducted on a high-resolution depth-averaged hydrodynamic model, using Telemac2D. Eight sites were investigated, representing the proposed developments at the time of study. These included: Ramsey Sound, Anglesey, Strangford Loch, Mull of Kintyre, Torr Head, Fair Head, Sound of Islay and West of Islay. Only three projects showed array-array interaction: Fair Head, Torr Head and Mull of Kintyre. A smaller model domain was created for further analysis. Results showed Mull of Kintyre had little impact. Fair Head reduced the energy production at Torr Head by 17%, whereas, Fair Head only reduced by 2%. This was caused by the tidal asymmetry whereby the flood was stronger. When operated concurrently, the maximum power-output at Torr Head is 64.5 MW, representing 31% reduction. If Torr Head can still operate commercially in the presence of Fair Head, then the additional environmental impact of Torr Head, such as the change in bed shear stress, is small. Within the Irish Sea, very few of the tidal projects investigated are geographically close to each other. As the industry develops, the risk of interaction to these sites will grow when more intermediary sites are developed

Modelling pollution dispersal around Solomon Islands and Vanuatu

To assess potential dispersion of pollutants around Honiara, Solomon Islands, and Port Vila, Vanuatu, 3D ocean circulation models were developed using Telemac-3D. A series of scenarios then explore the vulnerability of the system and test potential control measures. Results show that high coastal concentrations are most likely during the wet season, with increased volumes of discharge as well as favourable wind speed and direction. Buoyant plumes flow along the coastline, and high concentrations build up in enclosed bays. Control measures tested focus on consolidating existing outflows at depth off-shore. This results in an overall reduction of surface concentrations along the coastline. However, the reduction is dependent on the depth, off-shore positioning, and volume of outflow. With increased concentrations then found at depth, the subsequent impact on off-shore and benthic ecosystems would also need to be considered

The greggs-pret index: a machine learning analysis of consumer habits as a metric for the socio-economic north- south divide in England

In England, it is anecdotally remarked that the number of Greggs bakeries to be found in a town is a reliable measure of the area’s 'Northern-ness'. Conversely, a commercial competitor to Greggs in the baked goods and sandwiches market, Pret-a-Manger, is reputed to be popular in more 'southern' areas of England. Using a Support Vector Machine and an Artificial Neural Network (ANN) Regression Model, the relative geographical distributions of Greggs and Pret have been utilised for the first time to quantify the North-South divide in England. The calculated dividing lines were each compared to another line, based on Gross Domestic Household Income (GDHI). The lines match remarkably well, and we conclude that this is likely because much of England's wealth is concentrated in London, as are most of England's Pret-a-Manger shops. Further studies were conducted based on the relative geographical distributions of popular supermarkets Morrisons and Waitrose, which are also considered to have a North-South association. This analysis yields different results. For all metrics, the North-South dividing line passes close to the M1 Watford Gap services. As a common British idiom, this location is oft quoted as one point along the English North-South divide, and it is notable that this work agrees. This tongue-in-cheek analysis aims to highlight more serious factors highlighting the North-South divide, such as life expectancy, education, and poverty