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D-MOSS: An integrated dengue early warning system in Thu Vietnam driven by Earth Observations
No full textD-MOSS, Dengue MOsquito Simulation from Satellites, is a dengue fever early warning system for Vietnam being developed in a project funded by the UK Space Agency’s International Partnerships Programme. The D-MOSS project is developing a suite of innovative tools that will allow public health authorities to identify areas of high risk for disease epidemics before an outbreak occurs, in order to target resources to reduce spreading of epidemics and improve disease control. Beneficiaries will be enabled to issue alerts for dengue fever and provide assessments of vector-borne disease risk under future climate and land-use change scenarios. The D-MOSS architecture relies on open and non-proprietary software and on flexible deployment into platforms including cloud-based virtual storage and application processing. The tools produced will also be used to increase the understanding of climate change-related health risks during a period when Vietnam is developing an updated National Adaptation Plan in line with its Paris Agreement obligations. Before 1970 only nine countries had experienced severe dengue epidemics. Today the disease is endemic in 141 countries, affecting 390 million people and with a global annual cost estimated at almost US$9 billion, which is three times that of cholera and over four times that of gastroenteritis. Since 2000, there has been an increase of over 100% in the number of cases of dengue fever in Vietnam, with 185,000 cases occurring in 2017 alone, and there is currently no system for forecasting future dengue outbreaks. The D-MOSS project is developing a forecasting system in which EO datasets are combined with weather forecasts and a hydrological model to predict the likelihood of future dengue epidemics up to eight months in advance. D-MOSS integrates multiple stressors such as water availability, land-cover, precipitation and temperature. The approach integrates historical stressor datasets with each other and with historic dengue fever incidents, which are then input into a statistical model to provide forecasts based on future seasonal weather and hydrological forecasts. The D-MOSS project is within the first year of its three-year term and is currently focused on platform and model development, while gathering the key input data and engaging with the Vietnamese government to ensure that all components are fit for purpose. The portrayal system is designed to communicate the dengue and water availability forecasts to the Vietnamese Ministries of Health and Natural Resources and Environment. A user interface will also incorporate supporting information on recommended actions, provided by the decision makers and based on the forecasts and associated uncertainty. The D-MOSS project is led by HR Wallingford, working with the London School of Hygiene and Tropical Medicine, the Met Office and Oxford Policy Management in the UK, and with the following international partners: the United Nations Development Programme, the World Health Organisation, the Vietnamese Institute of Meteorology, Hydrology and Climate Change, the Pasteur Institute Ho Chi Minh City, and the National Institute of Hygiene and Epidemiology in Vietnam
The measurement and modelling of plumes resulting from deep sea mining of Fe-Mn crusts
No full textSeamounts are of great oceanographic interest because of their local and basin-scale influence over ocean systems, their often unique ecosystems, and because they are associated with the formation of ferromanganese (Fe-Mn) crusts. These crusts are rich in some of the rare elements increasingly required for development of renewable technologies, if viable and economical mining strategies can be developed to recover these resources. However, little is known about the potential for sediment (and chemical) plumes caused by deep sea mining to adversely affect the local ecosystem. The literature contains many references to the potential for mining to cause irreversible damage to the ecosystem but these are typically based on assumptions rather than evidence.
This paper describes studies undertaken as a part of the MarineE-tech UK funded project, investigating the geo-chemical processes governing, and environmental issues arising from the mining of, Fe-Mn crusts. In this project innovative monitoring approaches have been developed for monitoring deep sea sediment plumes and these approaches have been applied to the Tropic Seamount in the North East Atlantic. The data set, possibly the first of its kind, involves 21 different experiments and has been used to validate detailed and detailed hydrodynamic and sediment transport models as a basis for a predictive tool for assessing the effects of sediment plumes from deep sea mining. These models have deep sea plumes have been then used as tools for evaluating the potential effects of deep sea mining of the crust
Experimental observations of tsunami induced scour at onshore structures
No full textTsunami inundation of the coastal environment can induce scour at structure foundations leading to failure. A series of experiments are made using a unique Pneumatic Long Wave Generator to generate tsunami wave periods of 25–147 s equating to 3–17.3 min at 1:50 Froude scale. The waves propagate over a sloping bathymetry and impinge upon a square structure founded onshore in a flat sediment bed. Flow velocity, height and scour depth are recorded as a function of time during tsunami inundation. The rate of scour is observed to be time dependent. Equilibrium, which is not attained, is argued to be an inappropriate measure for time-dependent transient flows such as tsunami in which the flow velocity, depth and direction are variable. The maximum scour depth is recorded and critically is observed not to be equal to the final depth due to significant sediment slumping when flow velocities reduce in the latter stages of inundation. Current and wave scour predictor equations over predict the scour, while the ASCE 7–16 method under predicts. Comparisons with available data in the literature show longer inundation durations increase the amount of scour
Variability of sediment observations across the sand-mud inner shelf near Ocean City Inlet
No full textSediment samples were acquired along a cross-shore transect extending roughly 5 nautical miles offshore starting in 10 m water depth and ending in 17 m water depth near Ocean City Inlet, MD. Sediment sampling was repeated 3 times at 4 cross-shore stations during a series of cruises from May 2019 through July 2019. Diver push cores were logged, sectioned, and analyzed for grain size. A multibeam survey was conducted to map the bathymetry along the cross-shore transect. Additionally, regions around the sampling stations were surveyed with a side-scan sonar. Backscatter from the side-scan sonar correlates well with sediment observations. During one cruise in July 2019 water samples taken near the bed were analyzed with high-speed photogrammetry onboard the ship to estimate suspended sediments size and concentrations. Discussion will focus on understanding the hydrodynamic and geologic controls driving the strong sediment heterogeneity observed among the four stations along the cross-shore transect
Fast random wave generation in numerical tanks
Get PDFGenerating and absorbing random waves in numerical models is a challenging problem, in particular when meaningful wave statistics should be generated to meet design sea state requirements. The methodology presented herein allows for the generation of random wave fields (free surface elevation and velocities) to be reconstructed in time and in space by using window processing from a reference time series
Advanced tools for modelling fluid interaction with coastal and marine structures
Get PDFDue to the increasing availability of computational resources the Engineering and Research community is gradually moving towards using high fidelity Computational Fluid Dynamics (CFD) models for supporting technical design and specialized analysis. In this context, the CFD Toolkit Proteus is used to perform numerical modelling of physical processes pertaining to wave propagation within coastal and offshore environment and to fluid structure interaction
Decision-making for strengthening climate resilience: dealing with data paucity in the Caribbean water supply sector
No full textThe Caribbean accounts for seven of the world’s top 36 water-stressed countries and FAO defines many Caribbean countries as water scarce, with less than 1000 m3 freshwater resources per capita per year. Climate change will bring rising temperatures, increases in evaporation and potentially less rainfall. This means the Caribbean is likely to experience more intense and frequent droughts. Compounding this, paucity of data, lack of technical capacity and an absence of structured methodologies to assess and identify climate resilience measures has hindered evidence-based decision-making to address climate challenges in the water supply sector in the Caribbean.
This paper draws on experiences from five Caribbean countries – Grenada, St Kitts & Nevis, Dominica, Antigua & Barbuda and St Lucia – and their stakeholder-led processes assess climate risks, identify priorities for investment, and financing for their effective implementation. The countries followed a common structured approach centred on four key stages namely: Engaging stakeholders and setting objectives; Assessing risks and identifying options; Prioritising options and planning for implementation; and Monitoring and evaluating progress. As part of the approach, a series of national multi-stakeholder workshops, supplemented by the best available information and analyses, were used to define common objectives, analyse options and reach consensus on priorities. The combination of quantitative analyses, novel communication methods and expert elicitation led ultimately to the development of investment plans for improving climate resilience, whilst also building knowledge and capacity among national stakeholders along the way
Agent-Based Modelling of fish collisions with tidal turbines
Get PDFWith growing developments in marine tidal energy, coupled with high densities of marine species in suitable installation locations, there is concern about marine wildlife colliding with underwater devices. Methods are needed to predict such collisions when assessing environmental impacts of underwater turbines.
Agent-Based Models (ABMs) in the field of ecology: simulate interactions between organisms; assess how they live (i.e. grow, reproduce, function, adapt) and die in a dynamic physical environment; consider a population from the point of view of the individuals, or agents with population level behaviours emerging from the behaviour of the individuals; have individual within a system that are defined by traits
(e.g. size, age or sensitivity to a stressor) and behaviours
they can perform (e.g. migration or avoidance).
To better predict collisions with underwater devices, HR Wallingford has developed an Agent-Based Model (ABM) to predict the probability of marine animals colliding with an underwater device
Successful use of modelling for sustainable dredging projects
No full textRealizing sustainability in the development of water infrastructure, especially where dredging is concerned, is increasingly important in modern infrastructure design. This is because the incorporation of natural features and considerations into the design can provide economically advantageous schemes which also provide enhanced eco-system services. Modelling is a key part of achieving this goal – but rather than the use of modelling to merely avoid adverse impact, modelling can and should be used to explore opportunities to enhance nature alongside the provision of engineering infrastructure and provide win-win solutions.
Amongst the various different models normally considered in studies associated with sustainable infrastructure design, i.e. those involved with identifying potential physical and chemical effects ecological modelling now plays a much more expanded role. This ecological modelling includes a variety of different model types which incorporate the effects of biology and ranges from small enhancements of existing hydrodynamic models – such as the inclusion of the effects of drag caused by vegetation in wave models – to models representing more detailed aspects of biology - such as individual-based models (IBM) of fish behaviour or habitat models which evaluate changes in biomass under different environmental conditions. Examples of the use of these ecologically-orientated models in studies for sustainable development are presented and discussed.
The role of modelling in general - what it can do, what it can’t do, and what it needs to be used successfully - is often poorly understood and this in turn can lead to poorer design and environmental outcomes. In particular, there are differences in the way models need to be applied at different stages of the project and in the data requirements for each stage of modelling. The understanding of these differences, and in the way data collection needs to be incorporated into the project schedule, can be key to efficient design and gaining regulatory consent. This paper provides guidance on how different types and aspects of modelling integrate with the different phases of the project schedule - from planning and design and option selection, to impact assessment and construction management - and highlights the key considerations at each step
Developments in water resources planning in the United Kingdom: balancing bottom-up and top-down approaches
No full textWater companies in the United Kingdom are required to produce long-term plans of water resources for their supply area every five years, outlining how they plan to maintain secure and sustainable supplies, taking account of social and environmental impacts as well as economic costs. As a result, the water environment is highly regulated to ensure competing demands are satisfied. A quarter of the population lives in the south-east of the country, with water supplied by six different water companies. This region faces long term challenges of population growth, which is projected to grow at a rate exceeding the national average, and some areas predicted to face water supply deficits in the near future.
The recent WaterUK long term planning framework report concluded that large-scale inter-regional transfers of water could offer the best value to securing water resources on a national scale. However, the planning guidelines suggest that the complexity of the water resources planning method applied is proportional to the challenges faced by the individual water company. With the first regional water resource plans programmed for publication in 2022, regional bodies are facing the challenge of amalgamating results from the wide range of methods applied within their region. The absence of a one size fits all approach poses difficulties in assessing and modelling the viability and timing of such schemes.
We address how water companies and regional bodies are working together to produce integrated regional water resources and investment models to arrive at optimal solutions. Recent work by HR Wallingford demonstrates the benefits and limitations of such an optimised approach, as well as highlighting the initial challenges of planning a strategic inter-basin water transfer from the perspectives of water companies, regulators, and stakeholders in a region facing some of the most challenging water resources issues in the country