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Data quality, provenance and IPR Management services: their role in empowering geospatial data suppliers and users
Get PDFThis poster looks at current experiences of geospatial users and geospatial suppliers and how they have been limited by suitable frameworks for managing and communicating data quality, data provenance and intellectual property rights (IPR). Current political and technological drivers mean that increasing volumes of geospatial data are available through a plethora of different products and services, and whilst this is inherently a good thing it does create a new generation of challenges.
These challenges are that it has become more challenging and time consuming for users to appraise the value of data for their particular purpose. The second is that data suppliers are finding that traditional data licensing models are difficult to apply in a culture that is dominated by public ‘open data’.
This paper consider two examples of where these issues have been examined and looks at the challenges
and possible solutions from a data user and data supplier perspective. The first example is the EC FP7 IQmulus project that is researching fusion environments for big geospatial point clouds and coverages. The second example is the EU Emodnet programme that is establishing thematic data portals for public marine and coastal data
CFD Modelling of fall pipe rock dumping using PICIN
Get PDFIn this paper fall pipe rock dumping is investigated in 2D using the PICIN CFD model. PICIN employs the hybrid Eulerian-Lagrangian full particle Particle-In-Cell framework for incompressible free surface flow augmented with a full two-way fluid-solid interaction model. The PICIN model is first compared against a benchmark case of two circular particles falling in a water-filled tube. The results agree well with the numerical predictions of Patankar (2001). When applied to cases of randomly shaped rocks falling in pipe, the PICIN model seems to capture the physical processes and mechanisms that lead to clustering of the rocks
Issues for the assessment of sediment plumes arising from deep sea mining operations
Get PDFAs offshore mining becomes potentially more feasible for a variety of different minerals, there are increasingly more applications: in less well known environments; without the benefit of decades of monitoring; often with sensitive environmental issues; often without clearly defined path for gaining consent.
This poster considers some of the re-occurring themes that have occurred in recent offshore mining applications with regard to the physical processes and their numerical modelling
Sediment recycling to mitigate the effects of harbour deepening on habitat and what happened over the following 15 years
No full textPorts often have to confront the competing challenges of the competitive requirement for deeper channels and the need to preserve nearby important coastal wetlands which function as both habitat and flood defence. A good example of these competing pressures is found in the Stour/Orwell Estuary system which is internationally important for its wetland bird populations but is also the location of the Port of Felixstowe. The environmental value of the area has led to the intertidal areas of the estuary system being protected under European legislation with regulatory requirements for any proposed development at the port. This paper describes the implementation of an innovative large-scale sediment recycling scheme designed to offset the identified adverse effects of the 1998/2000 approach channel deepening on the estuary system. The sediment recycling involves the placement of a portion of the maintenance material from the Felixstowe berths and approaches within the Stour and Orwell Estuaries, maintaining the fine sediment budget and so mitigating the effects of port development whilst supporting the local ecosystem. The paper also describes how the sediment recycling was adapted and refined in response to feedback from local fishermen and as more information about the estuary evolution following the channel deepening became available
PICIN: A particle-in-cell slover for incompressible free surface flows with two-way fluid-solid coupling
No full textThis paper details a novel numerical approach for solution of the Navier–Stokes equations for free surface flows involving two-way fluid-solid interaction in arbitrary domains. The approach, which is hybrid Eulerian Lagrangian in nature, is based on the full particle particle-in-cell
(PIC) method applied to incompressible flows. An extension of the distributed Lagrange multiplier (DLM) technique proposed by Patankar et al. [Int. J. Multiphase Flow, 26 (2000), pp. 1509–1524] is employed for the two-way fluid-solid coupling. The resulting code is called PICIN. Solid bodies can be mobile, either having prescribed motion or moving as a consequence of interaction with the fluid.
Numerical results for three distinct example applications of the model in two spatial dimensions are given. A comparison of PICIN predictions with state-of-the-art numerical results of other researchers is made for each of the test cases presented
Numerical modelling of fish in response to underwater noise
Get PDFWater is an excellent medium for sound transmission, which leads to concern about anthropogenic noise impacts on sensitive species. Models now exist that can predict a soundscape, taking into account hydrodynamic features, such as stratification, and seabed properties. A key challenge is to predict ecological responses, particularly to inform
environmental impact assessments, prior to new marine developments. Individual and Agent Based Models (I/ABMs) provide an opportunity to assist in this ecological response prediction
A review of the physical impacts of sediment dispersion from aggregate dredging
No full textThe disturbance and subsequent dispersion of sediment arising from aggregate dredging results in increases in suspended sediment concentrations and, potentially, settlement of fine sediment or sand onto the bed, which may both cause adverse effects on local ecology. This subject is one area which has seen much research over many years and this paper sets out to synthesise some basic general conclusions for use when assessing the significance of planned operations. The literature detailing the dispersion of fine sediment plumes, and the longer term dispersion of sand released through the dredging process, is scrutinised, and in some cases re-evaluated, and used to identify an evidence-based footprint of potential impact
Underwater sound from dredging activities: establishing source levels and modelling the propagation of underwater sound
No full textUnderwater sound from anthropogenic sources and its potential adverse effects on the marine environment is a topic of much global interest. Concerns regarding anthropogenic underwater sound have historically been concerned with sonar from military activities, seismic survey work and percussive pile driving; however in recent years there has been a recognition that sound from some shipping and dredging activities could also impact on the marine environment.
Dredging activities emit underwater sound into the marine environment. Monitoring of sound from dredging equipment is often carried out for an individual project and usually only to support research; however, due to the way in which sound interacts with the marine environment the propagation of sound from individual dredging vessels will vary depending on the activity and location of the dredging. The level of sound at the dredger, termed the source level, will also vary between dredgers due to a range of different environmental and mechanical factors.
In this paper we present a brief review of the known sound source levels for various dredging equipment and activities, describe a method used to extrapolate source levels based on the pump power when a source level has not been directly measured, and describe how this information is used to predict the propagation of sound from dredging activities using numerical modelling tools
Application of a noise model for environmental impact assessment of deep sea mining
Get PDFThe Chatham Rise is a submarine feature extending
eastward from the South Island of New Zealand. The rise has water depths of 80 - 500m and hosts economically significant amounts of rock phosphate nodules on/within the seabed. Chatham Rock Phosphate (CRP) are planning to mine the phosphate using conventional dredging methodology adapted for deep water. CRP commissioned HR Wallingford to undertake underwater sound modelling for the mining operation. The sound modelling was undertaken to inform the environmental impact assessment of potential effects on commercial fish in the area. The model used was the HAMMER tool developed by HR Wallingford, which is a parabolic equation model similar in principle to RAM
The future of maintenance dredging: working with nature? A synthesis
No full textThe concept of ‘Working with Nature’ is now well established (PIANC, 2008 and 2011) and has been demonstrated by numerous capital dredging and marine construction projects, however, it is also a concept that can be applied to maintenance dredging. In the past it has been shown that the majority of material that arises from dredging operations, including maintenance material, is sent to designated offshore placement sites (e.g. EuDA, 2005). By design, the dredge material placement sites are often located outside the boundary of the relevant sediment transport system; in other words, ‘offshore and out of the system’. Displacing maintenance dredge material in this way can significantly affect the local and regional sediment budget, which in-turn can lead to potential (negative) morphological and ecological impacts. This paper discusses how the concept of ‘Working with Nature’ can be applied to maintenance dredging projects by considering: the effect of maintenance dredging on sediment budgets, examples of where ‘Working with Nature’ has been applied to maintenance dredging activities (including the use of different dredging techniques) and the potential issues that may be encountered in its application and how they can be overcome