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The energetic flows within the Alderney Race have attracted interest for harnessing tidal energy using tidal turbine arrays for electricity generation. The Race is split into French territorial waters in the East of the Race and Alderney territorial waters in the West. This presents an interesting optimisation problem where large scale blockage effects cause array development in the East to enhance the resource in the West and vice versa. This paper presents an initial study investigating the optimal number of turbines and their spatial distribution within the Alderney Race to help establish the most suitable long term development strategy. Computational simulations were conducted using OpenTidalFarm, a 2D non-linear shallow water hydrodynamic solver. The software uses efficient gradient-based methods for optimising the number of turbines and their spatial distribution within large arrays. Results show that the optimal turbine arrays within the East or West Race when considered in isolation are significantly different to those when optimisation is conducted for both the East and West Race together. This demonstrates that developing the sites separately without knowledge of the other sites development plan will have a detrimental effect on the total generated power and the cost of energy within the Alderney Race.

Tidal energy has the potential to form a key component of the energy mix of a number of countries, including the UK. Nonetheless, the deployment of tidal energy systems is associated with potential environmental impacts as prime resource sites often coincide with unique ecosystems inhabited by sensitive organisms. Preceding studies have generally focused on the hydrodynamic impact of tidal energy schemes, i.e. how schemes alter the flow dynamics and sedimentary transport processes. Whilst these efforts are key in understanding environmental impacts, there is no straightforward step for translating sediment to faunal changes. Species distribution models offer methods to quantitatively predict certain possible impacts of tidal energy extraction. The River Severn is a distinguished candidate region for tidal energy in the UK featuring sites under stringent ecological protection regulations. We examine the impact of a proposed Severn tidal barrage on 14 species via the linking of hydrodynamic modelling to species distribution models. Through a selection of species that are linked via a simple food web system we extrapolate changes in prey species to the respective predator species. We show that species at lower trophic levels are adversely affected by the barrage, but higher trophic level organisms increase in possible habitable area. Once food web relationships are acknowledged this increase in habitat area decreases, but is still net positive. Overall, all 14 species were affected, with most gaining in distribution area, and only four losing distribution area within the Severn Estuary. We conclude that a large-scale tidal barrage may have detrimental and complex impacts on species distribution, altering food web dynamics and threatening food availability in the Severn Estuary. The methodology outlined herein can be transferred to the assessment and optimisation of prospective projects globally to aide in the sustainable introduction of the technology.

of a talk presented in the VII International Conference on Adaptive Modeling and Simulation (ADMOS) in 2015, Nantes, France (an ECCOMAS thematic conference)

Pre-print submitted to the 2019 European Wave and Tidal Energy Conference (EWTEC).Presented 4 September 2019.

of a talk presented in the VII International Conference on Adaptive Modeling and Simulation (ADMOS) in 2015, Nantes, France (an ECCOMAS thematic conference)

Pre-print submitted to the 3rd International Conference on Renewable Energies Offshore conference (RENEW 2018, 8 - 10 October 2018, Lisbon, Portugal)

The depth of shallow seas exerts a strong control on water-body mixing, sedimentation and biodiversity but evaluating bathymetry in the geological past has traditionally proven challenging. Despite an extensive sedimentologic record and long history of geologic study, accurate estimates of water depth in the Cretaceous Western Interior Seaway, USA, remain uncertain. Herein paleotidal modelling, paleogeographic reconstructions and depositional process regimes are combined to evaluate the basin physiographic controls on tidal sedimentary processes in the region of the 'Utah Bight' of the Western Interior Seaway and thereby constrain paleobathymetric estimates. Paleotidal modelling using a global and astronomically-forced tidal model and paleobathymetric sensitivity tests suggest that tides were only able to transport silt or sand in the 'Utah Bight' if the seaway had a deeper basin center (~400 m) and a deeper southern entrance (>100 m) than previously estimated. This deeper paleobathymetry increased tidal inflow into the basin and enhanced local resonance effects in the 'Utah Bight'. Maximum tidal velocity vectors suggest a dominant south-easterly ebb tide, consistent with paleocurrent measurements from the Sego Sandstone. However, the preservation of tidal cross stratification in very fine- to fine-grained sandstones implies local tidal amplification below the maximum resolution of model meshes. Tidal modelling is shown to be a useful tool for evaluating paleobathymetry in ancient epicontinental seas at scales appropriate to mesh resolution.

Water Quality

Tidal range energy projects present an attractive means for the predictable and large-scale generation of electricity from the marine environment. In particular, proposals are under consideration in UK waters, with their feasibility currently being under high levels of scrutiny. This is due to a combination of potential environmental and socio-economic impacts that are challenging to quantify in the absence of a standardised methodology. At present, numerical models are being developed to provide robust resource/impact assessments and inform future designs. However, modelling inconsistencies in the representation of tidal power plants, operational algorithms, and turbine technology parameters can be observed in the studies to-date. This has made comparisons between proposed designs difficult to accomplish and rely upon. We present a series of models that progressively and consistently introduce spatial dimensions in resource prediction applications. The capabilities and limitations of each of these models are discussed with regard to the evaluation of energy resource and potential hydrodynamic impacts of tidal power plant proposals. Results highlight that a range of hydrodynamic scales should be considered, employing updated parametric models relating to the turbine technology capabilities. These steps will inform optimisation analyses and the robustness of tidal power plant proposals.

Renewable energy is the cornerstone of preventing dangerous climate change whilst main- taining a robust energy supply. Tidal energy will arguably play a critical role in the renewable energy portfolio as it is both predictable and reliable, and can be put in place across the globe. However, installation may impact the local and regional ecology via changes in tidal dynamics, sediment transport pathways or bathymetric changes. In or- der to mitigate these eects, tidal energy devices need to be modelled in order to predict hydrodynamic changes. Robust mesh generation is a fundamental component required for developing simulations with high accuracy. However, mesh generation for coastal domains can be an elaborate procedure. Here, we describe an approach combining mesh generators with Geographical Information Systems. We demonstrate robustness and e - ciency by constructing a mesh with which to examine the potential environmental impact of a tidal turbine farm installation in the Orkney Islands. The mesh is then used with two well-validated ocean models, to compare their ow predictions with and without a turbine array. The results demonstrate that it is possible to create an easy-to-use tool to generate high-quality meshes for combined coastal engineering, here tidal turbines, and coastal ocean simulations.

Modern mangroves are among the most carbon-rich biomes on Earth, but their long-term (≥10 6 years) impact on the global carbon cycle is unknown. The extent, productivity and preservation of mangroves are controlled by the interplay of tectonics, global sea level and sedimentation, including tide, wave and fluvial processes. The impact of these processes on mangrove-bearing successions in the Oligo-Miocene of the South China Sea (SCS) is evaluated herein. Palaeogeographic reconstructions, palaeotidal modelling and facies analysis suggest that elevated tidal range and bed shear stress optimized mangrove development along tide-influenced tropical coastlines. Preservation of mangrove organic carbon (OC) was promoted by high tectonic subsidence and fluvial sediment supply. Lithospheric storage of OC in peripheral SCS basins potentially exceeded 4,000 Gt (equivalent to 2,000 p.p.m. of atmospheric CO2). These results highlight the crucial impact of tectonic and oceanographic processes on mangrove OC sequestration within the global carbon cycle on geological timescales.

Rathlin Sound is an energetic tidal site that falls into the category of a strait between an island and a landmass. This paper presents a tidal resource assessment of Rathlin Sound based on simulations obtained from a validated numerical shallow flow solver. For an M2 tide, the natural flow conditions at the site exhibit local mean and maximum flow speeds of 2 and 3 m/s respectively. The upper limit to power extraction east of Rathlin Sound is found to be approximately 298 MW, which is not well approximated by either the undisturbed kinetic power or the power naturally dissipated at the seabed. An analytical model of a channel connecting two infinite ocean basins underpredicts maximum power extracted in Rathlin Sound due to changes in the head driving the flow with power extraction and the existence of an alternative flow path north of Rathlin Island. At maximum power extracted in Rathlin Sound, there is substantial reduction in mean flow speeds in the strait and to the south-east of Rathlin Sound. Maximum power extracted in the strait is reduced by 14 % and 36 % when the strait blockage ratio by the farm is 80 % and 60 % respectively. Implementation of power extraction offshore of the island in combination with power extraction in the strait yields higher power generation rates than isolated extraction either in the strait or offshore of the island. Outcomes of the resource assessment for Rathlin Sound are generally in good agreement with those for an idealised strait between an island and landmass.

Reliable and robust archival of model set-ups and outputs,including input data is a major challenge. Failure to do this ina robust and sustainable manner could lead to increased set–up costs for new studies, duplication and possible inconsistencies in model outputs. In addition, comprehensive archival of input and output data is an important step in ensuring reproducibility of results. In order to address these challenges, the utilities presented in this paper facilitate the automatic archival of model data, and publication in a citable repositories.

This poster describes the PyRDM library. It was presented at the 10th International Digital Curation Conference, which was held in London in February 2015.

Ocean modelling requires the production of high-fidelity computational meshes upon which to solve the equations of motion. The production of such meshes by hand is often infeasible, considering the complexity of the bathymetry and coastlines. The use of Geographical Information Systems (GIS) is therefore a key component to discretising the region of interest and producing a mesh appropriate to resolve the dynamics. However, all data associated with the production of a mesh must be provided in order to contribute to the overall recomputability of the subsequent simulation. This work presents the integration of research data management in QMesh, a tool for generating meshes using GIS. The tool uses the PyRDM library to provide a quick and easy way for scientists to publish meshes, and all data required to regenerate them, to persistent online repositories. These repositories are assigned unique identifiers to enable proper citation of the meshes in journal articles., Comment: Accepted, camera-ready version. To appear in the Proceedings of the 5th International Workshop on Semantic Digital Archives (http://sda2015.dke-research.de/), held in Pozna\'n, Poland on 18 September 2015 as part of the 19th International Conference on Theory and Practice of Digital Libraries (http://tpdl2015.info/)

The slides for the "Research Data Management for Computational Science" talk, given by Christian Jacobs on 5 June 2014 at Imperial College London. The talk briefly described the development and application of a software library, PyRDM, which aims to automate the publication of scientific software and data using online citable repositories such as Figshare.

Presentation given to EGU 2014. NH5.1, abstract: EGU2014-4052.

A report for an RDM Green Shoots project at Imperial College London, entitled "Research data management: Where software meets data".