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  • Journal article
    Rojas-Rueda D, de Nazelle A, Andersen ZJ, Braun-Fahrlaender C, Bruha J, Bruhova-Foltynova H, Desqueyroux H, Praznoczy C, Ragettli MS, Tainio M, Nieuwenhuijsen MJet al., 2016,

    Health impacts of active transportation in Europe

    , PLOS One, Vol: 11, ISSN: 1932-6203

    Policies that stimulate active transportation (walking and bicycling) have been related to heath benefits. This study aims to assess the potential health risks and benefits of promoting active transportation for commuting populations (age groups 16–64) in six European cities. We conducted a health impact assessment using two scenarios: increased cycling and increased walking. The primary outcome measure was all-cause mortality related to changes in physical activity level, exposure to fine particulate matter air pollution with a diameter <2.5 μm, as well as traffic fatalities in the cities of Barcelona, Basel, Copenhagen, Paris, Prague, and Warsaw. All scenarios produced health benefits in the six cities. An increase in bicycle trips to 35% of all trips (as in Copenhagen) produced the highest benefits among the different scenarios analysed in Warsaw 113 (76–163) annual deaths avoided, Prague 61 (29–104), Barcelona 37 (24–56), Paris 37 (18–64) and Basel 5 (3–9). An increase in walking trips to 50% of all trips (as in Paris) resulted in 19 (3–42) deaths avoided annually in Warsaw, 11(3–21) in Prague, 6 (4–9) in Basel, 3 (2–6) in Copenhagen and 3 (2–4) in Barcelona. The scenarios would also reduce carbon dioxide emissions in the six cities by 1,139 to 26,423 (metric tonnes per year). Policies to promote active transportation may produce health benefits, but these depend of the existing characteristics of the cities. Increased collaboration between health practitioners, transport specialists and urban planners will help to introduce the health perspective in transport policies and promote active transportation.

  • Journal article
    Quattrocchi G, Gorman GJ, Piggott MD, Cucco Aet al., 2016,

    M2, overtides and compound tides generation in the Strait of Messina: the response of a non-hydrostatic, finite-element ocean model

    , JOURNAL OF COASTAL RESEARCH, Pages: 657-661, ISSN: 0749-0208
  • Journal article
    Schlaphorst D, Kendall JM, Collier JS, Verdon JP, Blundy J, Baptie B, Latchman JL, Massin F, Bouin MPet al., 2016,

    Water, oceanic fracture zones and the lubrication of subducting plate boundaries-insights from seismicity

    , Geophysical Journal International, Vol: 204, Pages: 1405-1420, ISSN: 1365-246X

    We investigate the relationship between subduction processes and related seismicity for the Lesser Antilles Arc using the Gutenberg-Richter law. This power lawdescribes the earthquakemagnitude distribution, with the gradient of the cumulative magnitude distribution being commonly known as the b-value. The Lesser Antilles Arc was chosen because of its alongstrike variability in sediment subduction and the transition from subduction to strike-slip movement towards its northern and southern ends. The data are derived from the seismicity catalogues from the Seismic Research Centre of The University of the West Indies and the Observatoires Volcanologiques et Sismologiques of the Institut de Physique du Globe de Paris and consist of subcrustal events primarily from the slab interface. The b-value is found using a Kolmogorov-Smirnov test for a maximum-likelihood straight line-fitting routine. We investigate spatial variations in b-values using a grid-search with circular cells as well as an along-arc projection. Tests with different algorithms and the two independent earthquake cataloges provide confidence in the robustness of our results. We observe a strong spatial variability of the b-value that cannot be explained by the uncertainties. Rather than obtaining a simple north-south b-value distribution suggestive of the dominant control on earthquake triggering being water released from the sedimentary cover on the incoming American Plates, or a b-value distribution that correlates with on the obliquity of subduction, we obtain a series of discrete, high b-value 'bull's-eyes' along strike. These bull's-eyes, which indicate stress release through a higher fraction of small earthquakes, coincide with the locations of known incoming oceanic fracture zones on the American Plates. We interpret the results in terms of water being delivered to the Lesser Antilles subduction zone in the vicinity of fracture zones providing lubrication and thus changing the character of the related

  • Journal article
    Ball WT, Haigh JD, Rozanov EV, Kuchar A, Sukhodolov T, Tummon F, Shapiro AV, Schmutz Wet al., 2016,

    High solar cycle spectral variations inconsistent with stratospheric ozone observations

    , Nature Geoscience, Vol: 9, Pages: 206-209, ISSN: 1752-0894
  • Journal article
    Huddart JEA, Thompson MSA, Woodward G, Brooks SJet al., 2016,

    Citizen science: from detecting pollution to evaluating ecological restoration

    , Wiley Interdisciplinary Reviews: Water, Vol: 3, Pages: 287-300, ISSN: 2049-1948
  • Journal article
    Sen Gupta A, McGregor S, van Sebille E, Ganachaud A, Brown J, Santoso Aet al., 2016,

    Future changes to the Indonesian Throughflow and Pacific circulation: The differing role of wind and deep circulation changes

    , Geophysical Research Letters, Vol: 43, Pages: 1669-1678, ISSN: 0094-8276

    Climate models consistently project a substantial decrease in the Indonesian Throughflow (ITF) in response to enhanced greenhouse warming. On interannual timescales ITF changes are largely related to tropical Pacific wind variability. However, on the multidecadal timescales investigated here we demonstrate that regional winds and associated changes in the upper ocean circulation cannot explain the projected ITF decrease. Instead, the decrease is related to a weakening in the northward flow of deep waters entering the Pacific basin at ~40°S and an associated reduction in the net basin-wide upwelling to the north of the southern tip of Australia. This can be traced back to consistent changes in the Antarctic Circumpolar Current and Southern Ocean overturning, although questions still remain as to the ultimate drivers. In contrast to the ITF decrease, substantial projected changes to the upper ocean circulation of the Pacific basin are well explained by robust changes in the surface winds.

  • Journal article
    Smith R, Hill J, Collins GS, Piggott MD, Kramer S, Parkinson S, Wilson Cet al., 2016,

    Comparing approaches for numerical modelling of tsunami generation by deformable submarine slides

    , Ocean Modelling, Vol: 100, Pages: 125-140, ISSN: 1463-5003

    Tsunami generated by submarine slides are arguably an under-consideredrisk in comparison to earthquake-generated tsunami. Numerical simulationsof submarine slide-generated waves can be used to identify the important factorsin determining wave characteristics. Here we use Fluidity, an open sourcefinite element code, to simulate waves generated by deformable submarineslides. Fluidity uses flexible unstructured meshes combined with adaptivitywhich alters the mesh topology and resolution based on the simulationstate, focussing or reducing resolution, when and where it is required. Fluidityalso allows a number of different numerical approaches to be taken tosimulate submarine slide deformation, free-surface representation, and wavegeneration within the same numerical framework. In this work we use amulti-material approach, considering either two materials (slide and waterwith a free surface) or three materials (slide, water and air), as well as asediment model (sediment, water and free surface) approach. In all casesthe slide is treated as a viscous fluid. Our results are shown to be consistentwith laboratory experiments using a deformable submarine slide, anddemonstrate good agreement when compared with other numerical models.The three different approaches for simulating submarine slide dynamics andtsunami wave generation produce similar waveforms and slide deformationgeometries. However, each has its own merits depending on the application.Mesh adaptivity is shown to be able to reduce the computational cost withoutcompromising the accuracy of results.

  • Journal article
    Huang X, Restuccia F, Gramola M, Rein Get al., 2016,

    Experimental Study of the Formation and Collapse of an Overhang in the Surface Spread of Smouldering Peat Fires

    , Combustion and Flame, Vol: 168, Pages: 393-402, ISSN: 1556-2921

    Smouldering combustion is the driving phenomenon of wildfires in peatlands, and is responsible for large amounts of carbon emissions and haze episodes world wide. Compared to flaming fires, smouldering is slow, low-temperature, flameless, and most persistent, yet it is poorly understood. Peat, as a typical organic soil, is a porous and charring natural fuel, thus prone to smouldering. The spread of smouldering peat fire is a multidimensional phenomenon, including two main components: in-depth vertical and surface lateral spread. In this study, we investigate the lateral spread of peat fire under various moisture and wind conditions. Visual and infrared cameras as well as a thermocouple array are used to measure the temperature profile and the spread rate. For the first time the overhang, where smouldering spreads fastest beneath the free surface, is observed in the laboratory, which helps understand the interaction between oxygen supply and heat losses. The periodic formation and collapse of overhangs is observed. The overhang thickness is found to increase with moisture and wind speed, while the spread rate decreases with moisture and increases with wind speed. A simple theoretical analysis is proposed and shows that the formation of overhang is caused by the spread rate difference between the top and lower peat layers as well as the competition between oxygen supply and heat losses.

  • Journal article
    Almeida S, Le Vine N, McIntyre N, Wagener T, Buytaert Wet al., 2016,

    Accounting for dependencies in regionalized signatures for predictions in ungauged catchments

    , Hydrology and Earth System Sciences, Vol: 20, Pages: 887-901, ISSN: 1607-7938

    A recurrent problem in hydrology is the absence of streamflow data to calibrate rainfall-runoff models. A commonly used approach in such circumstances conditions model parameters on regionalized response signatures. While several different signatures are often available to be included in this process, an outstanding challenge is the selection of signatures that provide useful and complementary information. Different signatures do not necessarily provide independent information and this has led to signatures being omitted or included on a subjective basis. This paper presents a method that accounts for the inter-signature error correlation structure so that regional information is neither neglected nor double-counted when multiple signatures are included. Using 84 catchments from the MOPEX database, observed signatures are regressed against physical and climatic catchment attributes. The derived relationships are then utilized to assess the joint probability distribution of the signature regionalization errors that is subsequently used in a Bayesian procedure to condition a rainfall-runoff model. The results show that the consideration of the inter-signature error structure may improve predictions when the error correlations are strong. However, other uncertainties such as model structure and observational error may outweigh the importance of these correlations. Further, these other uncertainties cause some signatures to appear repeatedly to be misinformative.

  • Journal article
    Hoque MA, Scheelbeek PFD, Vineis P, Khan AE, Ahmed KM, Butler APet al., 2016,

    Drinking water vulnerability to climate change and alternatives for adaptation in coastal South and South East Asia

    , Climatic Change, Vol: 136, Pages: 247-236, ISSN: 0165-0009

    Drinking water in much of Asia, particularly in coastal and rural settings, isprovided by a variety of sources, which are widely distributed and frequently managed atan individual or local community level. Coastal and near-inland drinking water sources inSouth and South East (SSE) Asia are vulnerable to contamination by seawater, mostdramatically from tropical cyclone induced storm surges. This paper assesses spatialvulnerabilities to salinisation of drinking water sources due to meteorological variabilityand climate change along the (ca. 6000 km) coastline of SSE Asia. The risks of increasingclimatic stresses are first considered, and then maps of relative vulnerability along theentire coastline are developed, using data from global scale land surface models, alongwith an overall vulnerability index. The results show that surface and near-surfacedrinking water in the coastal areas of the mega-deltas in Vietnam and Bangladesh-Indiaare most vulnerable, putting more than 25 million people at risk of drinking ‘saline’ water.Climate change is likely to exacerbate this problem, with adverse consequences for health,such as prevalence of hypertension and cardiovascular diseases. There is a need foridentifying locations that are most at risk of salinisation in order for policy makers andlocal officials to implement strategies for reducing these health impacts. To counter therisks associated with these vulnerabilities, possible adaptation measures are also outlined.

  • Journal article
    Stanley E, Plant J, Voulvoulis N, 2016,

    Environmental chemical exposures and breast cancer

    , AIMS Environmental Science, Vol: 3, Pages: 96-114, ISSN: 2372-0352

    As a hormone-sensitive condition with no single identifiable cause, breast cancer is a major health problem. It is characterized by a wide range of contributing factors and exposures occurring in different combinations and strengths across a lifetime that may be amplified during periods of enhanced developmental susceptibility and impacted by reproductive patterns and behaviours. The vast majority of cases are oestrogen-receptor positive and occur in women with no family history of the disease suggesting that modifiable risk factors are involved. A substantial body of evidence now links oestrogen-positive breast cancer with environmental exposures. Synthetic chemicals capable of oestrogen mimicry are characteristic of industrial development and have been individually and extensively assessed as risk factors for oestrogen-sensitive cancers. Existing breast cancer risk assessment tools do not take such factors into account. In the absence of consensus on causation and in order to better understand the problem of escalating incidence globally, an expanded, integrated approach broadening the inquiry into individual susceptibility breast cancer is proposed. Applying systems thinking to existing data on oestrogen-modulating environmental exposures and other oestrogenic factors characteristic of Westernisation and their interactions in the exposure, encompassing social, behavioural, environmental, hormonal and genetic factors, can assist in understanding cancer risks and the pursuit of prevention strategies. A new conceptual framework based on a broader understanding of the “system” that underlies the development of breast cancer over a period of many years, incorporating the factors known to contribute to breast cancer risk, could provide a new platform from which government and regulators can promulgate enhanced and more effective prevention strategies.

  • Journal article
    Mac Dowell N, Staffell I, 2016,

    The role of flexible CCS in the UK's future energy system

    , International Journal of Greenhouse Gas Control, Vol: 48, Pages: 327-344, ISSN: 1750-5836

    That CCS will be required to operate in a flexible and load following fashion in the diverse energy landscape of the 21st century is well recognised. However, what is less well understood is how these plants will be dispatched at the unit generator scale, and what effect this will have on the performance and behaviour of the plant at the individual unit operation level. To address this gap, we couple an investment and unit commitment energy system model with a detailed plant-level model of a super-critical coal-fired power station integrated with an amine-based post-combustion CO2 capture process. We provide insight into the likely role of coal and gas CCS plants in the UK's energy system in the 2030s, 2040s and 2050s. We then evaluate the impact that this has on the performance of an individual coal CCS plant operating in this system, and chart its evolution throughout this period. Owing to the increased frequency and duration of part-load operation, asset utilisation and average efficiency suffer, leading to a substantially increased LCOE, implying that CCS costs will need to decrease more rapidly than is currently expected. Further, as a direct consequence of the dynamic operation, the interaction of the CCS plants with the downstream CO2 transport network is characterised by highly transient behaviour, including periods during which no CO2 is injected to the transport network, implying that the transport system must therefore be designed to incorporate this variability of supply.

  • Journal article
    Barraclough TG, Bell TDC, Rivett D, Scheuerl T, Mombrikotb S, Culbert C, Johnstone Eet al., 2016,

    Resource-dependent attenuation of species interactions during bacterial succession

    , ISME Journal, Vol: 10, Pages: 2259-2268, ISSN: 1751-7362

    Bacterial communities are vital for many economically and ecologically important processes. The role of bacterial community composition in determining ecosystem functioning depends critically on interactions among bacterial taxa. Several studies have shown that, despite a predominance of negative interactions in communities, bacteria are able to display positive interactions given the appropriate evolutionary or ecological conditions. We were interested in how interspecific interactions develop over time in a naturalistic setting of low resource supply rates. We assembled aquatic bacterial communities in microcosms and assayed the productivity (respiration and growth) and substrate degradation while tracking community composition. The results demonstrated that while bacterial communities displayed strongly negative interactions during the early phase of colonisation and acclimatisation to novel biotic and abiotic factors, this antagonism declined over time towards a more neutral state. This was associated with a shift from use of labile substrates in early succession to use of recalcitrant substrates later in succession, confirming a crucial role of resource dynamics in linking interspecific interactions with ecosystem functioning.

  • Journal article
    Kramer SC, Piggott MD, 2016,

    A correction to the enhanced bottom drag parameterisation of tidal turbines

    , Renewable Energy, Vol: 92, Pages: 385-396, ISSN: 1879-0682

    Hydrodynamic modelling is an important tool for the development of tidalstream energy projects. Many hydrodynamic models incorporate the effect oftidal turbines through an enhanced bottom drag. In this paper we show thatalthough for coarse grid resolutions (kilometre scale) the resulting force exertedon the flow agrees well with the theoretical value, the force starts decreasingwith decreasing grid sizes when these become smaller than the length scale ofthe wake recovery. This is because the assumption that the upstream velocitycan be approximated by the local model velocity, is no longer valid. Using linearmomentum actuator disc theory however, we derive a relationship between thesetwo velocities and formulate a correction to the enhanced bottom drag formulationthat consistently applies a force that remains close to the theoretical value,for all grid sizes down to the turbine scale. In addition, a better understandingof the relation between the model, upstream, and actual turbine velocity, aspredicted by actuator disc theory, leads to an improved estimate of the usefullyextractable energy. We show how the corrections can be applied (demonstratedhere for the models MIKE 21 and Fluidity) by a simple modification of the dragcoefficient.

  • Journal article
    Emmott CJM, Moia D, Sandwell P, Ekins-Daukes N, Hosel M, Lukoschek L, Amarasinghe C, Krebs FC, Nelson Jet al., 2016,

    In-situ, long-term operational stability of organic photovoltaics for off-grid applications in Africa

    , Solar Energy Materials and Solar Cells, Vol: 149, Pages: 284-293, ISSN: 0927-0248
  • Journal article
    Herceg TM, Yoon S-H, Abidin MSZ, Greenhalgh ES, Bismarck A, Shaffer MSPet al., 2016,

    Thermosetting nanocomposites with high carbon nanotube loadings processed by a scalable powder based method

    , Composites Science and Technology, Vol: 127, Pages: 62-70, ISSN: 0266-3538

    A powder based processing route was developed to allow manufacturing of thermosettingnanocomposites with high (20 wt%) carbon nanotube (CNT) loading fractions. Adaptation ofhigh shear mixing methods, as used in thermoplastic processing, ensured that the CNTs werewell distributed and dispersed even at the highest loadings. By minimising flow distances,compression moulding of powders ensured that the CNTs did not agglomerate duringconsolidation, and yielded a percolated CNT network in a nanocomposite with excellentelectrical and thermal conductivities of 67 S m-1and 0.77 W m-1 K-1, respectively. Unusually,the CNTs provided effective mechanical reinforcement at even the highest loadings;embrittlement is minimised by avoiding large scale inhomogeneities and the maximummeasured Young’s modulus (5.4 GPa) and yield strength (90 MPa) could make thenanocomposite an attractive matrix for continuous fibre composites. The macromechanicalmeasurements were interpolated using micromechanical models that were previouslysuccessfully applied at the nanoscale.

  • Journal article
    Pusch A, Yoshida M, Hylton NP, Mellor A, Phillips CC, Hess O, Ekins-Daukes NJet al., 2016,

    Limiting efficiencies for intermediate band solar cells with partial absorptivity: the case for a quantum ratchet

    , Progress in Photovoltaics, Vol: 24, Pages: 656-662, ISSN: 1099-159X

    The intermediate band solar cell (IBSC) concept aims to improve upon theShockley-Queisser limit for single bandgap solar cells by also making use ofbelow bandgap photons through sequential absorption processes via an intermediateband (IB). Current proposals for IBSCs suffer from low absorptivityvalues for transitions into and out of the IB. We therefore devise and evaluate ageneral, implementation-independent thermodynamic model for an absorptivityconstrainedlimiting efficiency of an IBSC to study the impact of absorptivitylimitations on IBSCs. We find that, due to radiative recombination via the IB,conventional IBSCs cannot surpass the Shockley-Queisser limit at an illuminationof one Sun unless the absorptivity from the valence band (VB) to the IBand the IB to the conduction band (CB) exceeds ≈ 36%. In contrast, the introductionof a quantum ratchet into the IBSC to suppress radiative recombinationcan enhance the efficiency of an IBSC beyond the Shockley-Queisser limit forany value of the IB absorptivity. Thus, the quantum ratchet could be the vitalnext step to engineer IBSCs that are more efficient than conventional single gapsolar cells.

  • Journal article
    Cotter CJ, Kuzmin D, 2016,

    Embedded discontinuous Galerkin transport schemes with localised limiters

    , Journal of Computational Physics, Vol: 311, Pages: 363-373, ISSN: 0021-9991

    Motivated by finite element spaces used for representation of temperature in the compatible fi-nite element approach for numerical weather prediction, we introduce locally bounded transportschemes for (partially-)continuous finite element spaces. The underlying high-order transportscheme is constructed by injecting the partially-continuous field into an embedding discontinuousfinite element space, applying a stable upwind discontinuous Galerkin (DG) scheme, and projectingback into the partially-continuous space; we call this an embedded DG transport scheme. Weprove that this scheme is stable in L2 provided that the underlying upwind DG scheme is. Wethen provide a framework for applying limiters for embedded DG transport schemes. StandardDG limiters are applied during the underlying DG scheme. We introduce a new localised form ofelement-based flux-correction which we apply to limiting the projection back into the partiallycontinuousspace, so that the whole transport scheme is bounded. We provide details in the specificcase of tensor-product finite element spaces on wedge elements that are discontinuous P1/Q1 inthe horizontal and continuous P2 in the vertical. The framework is illustrated with numericaltests.

  • Journal article
    Manz B, Buytaert W, Zulkafli Z, Lavado W, Willems B, Robles LA, Rodríguez-Sánchez J-Pet al., 2016,

    High-resolution Satellite-Gauge Merged Precipitation Climatologies of the Tropical Andes

    , Journal of Geophysical Research: Atmospheres, Vol: 121, Pages: 1190-1207, ISSN: 2169-897X

    Satellite precipitation products are becoming increasingly useful to complement rain gauge networks in regions where these are too sparse to capture spatial precipitation patterns, such as in the tropical Andes. The Tropical Rainfall Measuring Mission Precipitation Radar (TPR) was active for 17 years (1998 - 2014) and has generated one of the longest single-sensor, high-resolution and high-accuracy rainfall records. In this study, high-resolution (5 km) gridded mean monthly climatological precipitation is derived from the raw orbital TPR data (TRMM 2A25) and merged with 723 rain gauges using multiple satellite-gauge (S-G) merging approaches. The resulting precipitation products are evaluated by cross-validation and catchment water balances (runoff ratios) for 50 catchments across the tropical Andes. Results show that the TPR captures major synoptic and seasonal precipitation patterns and also accurately defines orographic gradients, but underestimates absolute monthly rainfall rates. The S-G merged products presented in this study constitute an improved source of climatological rainfall data, outperforming the gridded TPR product as well as a rain gauge-only product based on ordinary kriging. Among the S-G merging methods, performance of inverse-distance interpolation of satellite-gauge residuals was similar to that of geostatistical methods, which were more sensitive to gauge network density. High uncertainty and low performance of the merged precipitation products predominantly affected regions with low and intermittent precipitation regimes (e.g. Peruvian Pacific coast) and is likely linked to the low TPR sampling frequency. All S-G merged products presented in this study are available in the public domain.

  • Journal article
    Lozano FJ, Freire P, Guillen-Gozalbez G, Jimenez-Gonzalez C, Sakao T, Mac Dowell N, Gabriela Ortiz M, Trianni A, Carpenter A, Viveros Tet al., 2016,

    New perspectives for sustainable resource and energy use, management and transformation: approaches from green and sustainable chemistry and engineering

    , Journal of Cleaner Production, Vol: 118, Pages: 1-3, ISSN: 0959-6526
  • Journal article
    Nomura S, Parsons AJQ, Hirabayashi M, Kinoshita R, Liao Y, Hodgson Set al., 2016,

    Social determinants of mid- to long-term disaster impacts on health: A systematic review

    , International Journal of Disaster Risk Reduction, Vol: 16, Pages: 53-67, ISSN: 2212-4209

    Disasters cause a wide range of health impacts. Although there remains a need to understand and improve acute disaster management, a stronger understanding of how health is affected in the medium and longer term is also required to inform the design and delivery of measures to manage post-disaster health risks, and to guide actions taken before and during events which will also lead to reduction in health impact. Social determinants exert a powerful influence on different elements of risk, principally vulnerability, exposure and capacity, and thus, on people's health. As disaster health data and research has tended to focus on the short-term health impacts, no systematic assessment of the social determinants of the mid- to long-term health impacts of disasters has been identified. We assessed the chronic health impacts of disasters and explored the potential socioeconomic determinants of health impact through a systematic review. Our findings, based on 28 studies, highlighted that regardless of health outcomes and event types, the influence of disasters on chronic heath persists beyond the initial disaster period, affecting people's health for months to years. Using the World Health Organization's conceptual framework for the social determinants of health, we identified a total of 35 themes across the three conceptual domains (determinants related to the socioeconomic and political context, structural determinants, and intermediate determinants) as potentially influencing disaster impact. Investment to tackle modifiable underlying determinants could aid disaster risk management, improve medium and long-term health outcomes from disasters, and build community resilience.

  • Journal article
    Yit Sen Bull C, van Sebille E, 2016,

    Sources, fate, and pathways of Leeuwin Current water in the Indian Ocean and Great Australian Bight: A Lagrangian study in an eddy-resolving ocean model

    , Journal of Geophysical Research: Oceans, Vol: 121, Pages: 1626-1639, ISSN: 2169-9291

    The Leeuwin Current is the dominant circulation feature in the eastern Indian Ocean, transporting tropical and subtropical water southward. Whilst it is known that the Leeuwin Current draws its water from a multitude of sources, existing Indian Ocean circulation schematics have never quantified the fluxes of tropical and subtropical source water flowing into the Leeuwin Current. This paper uses virtual Lagrangian particles to quantify the transport of these sources along the Leeuwin Current's mean pathway. Here, the pathways and exchange of Leeuwin Current source waters across six coastally bound sectors on the south-west Australian coast are analysed. This constitutes the first quantitative assessment of Leeuwin Current pathways within an offline, 50-year integration time, eddy-resolving global ocean model simulation. Along the Leeuwin Current's pathway we find a mean poleward transport of 3.7 Sv in which the tropical sources account for 60-78% of the transport. Whilst the net transport is small, we see large transports flowing in and out of all the offshore boundaries of the Leeuwin Current sectors. Along the Leeuwin Current's pathway, we find that water from the Indonesian Throughflow contributes 50-66% of the seasonal signal. By applying conditions on the routes particles take entering the Leeuwin Current, we find particles are more likely to travel offshore north of 30°S, while south of 30°S particles are more likely to continue downstream. We find a 0.2 Sv pathway of water from the Leeuwin Current's source regions, flowing through the entire Leeuwin Current pathway into the Great Australian Bight.

  • Journal article
    Koppelaar RHEM, Keirstead J, Shah N, Woods Jet al., 2016,

    A review of policy analysis purpose and capabilities of electricity system models

    , Renewable & Sustainable Energy Reviews, Vol: 59, Pages: 1531-1544, ISSN: 1364-0321
  • Journal article
    Chayen N, shaffer, govada, Khurshid, Kassen, Leese H S, Hu S, Menzel, Chain B, Saridakiset al., 2016,

    Exploring Carbon Nanomaterial Diversity for Nucleation of Protein Crystals

    , Scientific Reports, Vol: 6, ISSN: 2045-2322

    Controlling crystal nucleation is a crucial step in obtaining high quality protein crystals for structure determination by X-ray crystallography. Carbon nanomaterials (CNMs) including carbon nanotubes, graphene oxide, and carbon black provide a range of surface topographies, porosities and length scales; functionalisation with two different approaches, gas phase radical grafting and liquid phase reductive grafting, provide routes to a range of oligomer functionalised products. These grafted materials, combined with a range of controls, were used in a large-scale assessment of the effectiveness for protein crystal nucleation of 20 different carbon nanomaterials on five proteins. This study has allowed a direct comparison of the key characteristics of carbon-based nucleants: appropriate surface chemistry, porosity and/or roughness are required. The most effective solid system tested in this study, carbon black nanoparticles functionalised with poly(ethylene glycol) methyl ether of mean molecular weight 5000, provides a novel highly effective nucleant, that was able to induce crystal nucleation of four out of the five proteins tested at metastable conditions.

  • Journal article
    Loveridge R, Wearn OR, Vieira M, Bernard H, Ewers RMet al., 2016,

    Movement behaviour of native and invasive small mammals shows logging may facilitate invasion in a tropical rainforest

    , Biotropica, Vol: 48, Pages: 373-380, ISSN: 1744-7429

    Invasive species pose one of the greatest threats to biodiversity. This study investigates the extent to which human disturbance to natural ecosystems facilitates the spread of non-native species, focusing on a small mammal community in selectively logged rainforest, Sabah, Borneo. The microhabitat preferences of the invasive Rattus rattus and three native species of small mammal were examined in three-dimensional space by combining the spool-and-line technique with a novel method for quantifying fine-scale habitat selection. These methods allowed the detection of significant differences for each species between the microhabitats used compared with alternative, available microhabitats that were avoided. Rattus rattus showed the greatest preference for heavily disturbed habitats and, in contrast to two native small mammals of the genus Maxomys, R. rattus showed high levels of arboreal behaviour, frequently leaving the forest floor and travelling through the under and mid-storey forest strata. This behaviour may enable R. rattus to effectively utilize the complex three-dimensional space of the lower strata in degraded forests, which is characterized by dense vegetation. The behavioural flexibility of R. rattus to operate in both terrestrial and arboreal space may facilitate its invasion into degraded forests. Human activities that generate heavily disturbed habitats preferred by R. rattus may promote the establishment of this invasive species in tropical forests in Borneo, and possibly elsewhere. We present this as an example of a synergistic effect, whereby forest disturbance directly threatens biodiversity, and indirectly increases the threat posed by invasive species, creating habitat conditions that facilitate the establishment of non-native fauna.

  • Journal article
    Woodward RT, Fam DWH, Anthony DB, Hong J, McDonald TO, Petit C, Shaffer MSP, Bismarck Aet al., 2016,

    Hierarchically porous carbon foams from pickering high internal phase emulsions

    , Carbon, Vol: 101, Pages: 253-260, ISSN: 0008-6223

    Carbon foams were produced from a macroporous poly(divinylbenzene) (poly(DVB) precursor, synthesized by polymerizing the continuous but minority phase of water-in-oil high internal phase emulsions (HIPEs) stabilized by molecular and/or particulate emulsifiers. Both permeable and non-permeable hierarchically porous carbon foams, or ‘carboHIPEs’, were prepared by carbonization of the resulting macroporous polymers at 800 °C. The carbon yields were as high as 26 wt.% of the original polymer. CarboHIPEs retain the pore structure of the macroporous polymer precursor, but with surface areas of up to 505 m2/g and excellent electrical conductivities of 81 S/m. Contrary to some previous reports, the method does not require further modification, such as sulfonation or additional crosslinking of the polyHIPE prior to carbonization, due to the inherently crosslinked structure of poly(DVB). The use of a pourable, aqueous emulsion-template enables simple moulding, minimises waste and avoids the strong acid treatments used to remove many conventional solid-templates. The retention of the macroporous structure is coupled with the introduction of micropores during carbonization, producing hierarchically porous carboHIPEs, suitable for a wide range of applications as sorbents and electrodes.

  • Journal article
    Ang CDE, Rein G, Peiro J, Harrison Ret al., 2016,

    Simulating longitudinal ventilation flows in long tunnels: comparison of full CFD and multi-scale modelling approaches in FDS6

    , Tunnelling and Underground Space Technology, Vol: 52, Pages: 119-126, ISSN: 0886-7798

    The accurate computational modelling of airflows in transport tunnels is needed for regulations compliance, pollution and fire safety studies but remains a challenge for long domains because the computational time increases dramatically. We simulate air flows using the open-source code FDS 6.1.1 developed by NIST, USA. This work contains two parts. First we validate FDS6’s capability for predicting the flow conditions in the tunnel by comparing the predictions against on-site measurements in the Dartford Tunnel, London, UK, which is 1200 m long and 8.5 m in diameter. The comparison includes the average velocity and the profile downstream of an active jet fan up to 120 m. Secondly, we study the performance of the multi-scale modelling approach by splitting the tunnel into CFD domain and a one-dimensional domain using the FDS HVAC (Heating, Ventilation and Air Conditioning) feature. The work shows the average velocity predicted by FDS6 using both the full CFD and multi-scale approaches is within the experimental uncertainty of the measurements. Although the results showed the prediction of the downstream velocity profile near the jet fan falls outside the on-site measurements, the predictions at 80 m and beyond are accurate. Our results also show multi-scale modelling in FDS6 is as accurate as full CFD but up to 2.2 times faster and that computational savings increase with the length of the tunnel. This work sets the foundation for the next step in complexity with fire dynamics introduced to the tunnel.

  • Journal article
    Blamey J, Fennell P, Anthony E, Dugwell D, Zhao M, Manovic Vet al., 2016,

    A shrinking core model for steam hydration of CaO-based sorbents cycled for CO2 capture

    , Chemical Engineering Journal, Vol: 291, Pages: 298-305, ISSN: 1873-3212

    Calcium looping is a developing CO2 capture technology. It is based on the reversiblecarbonation of CaO sorbent, which becomes less reactive upon cycling. One method ofincreasing the reactivity of unreactive sorbent is by hydration in the calcined (CaO) form.Here, sorbent has been subjected to repeated cycles of carbonation and calcination within asmall fluidised bed reactor. Cycle numbers of 0 (i.e., one calcination), 2, 6 and 13 have beenstudied to generate sorbents that have been deactivated to different extents. Subsequently,the sorbent generated was subjected to steam hydration tests within a thermogravimetricanalyser, using hydration temperatures of 473, 573 and 673 K. Sorbents that had beencycled less prior to hydration hydrated rapidly. However, the more cycled sorbents exhibitedbehaviour where the hydration conversion tended towards an asymptotic value, which is likelyto be associated with pore blockage. This asymptotic value tended to be lower at higherhydration temperatures; however, the maximum rate of hydration was found to increase withincreasing hydration temperature. A shrinking core model has been developed and applied to 2the data. It fits data from experiments that did not exhibit extensive pore blockage well, butfits data from experiments that exhibited pore blockage less well

  • Journal article
    Zhao R, Zhuge W, Zhang Y, Yang M, Martinez-Botas Ret al., 2016,

    Numerical study of a two-stage turbine characteristic under pulsating flow conditions

    , JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY, Vol: 30, Pages: 557-565, ISSN: 1738-494X
  • Journal article
    Lanzini A, Guerra C, Leone P, Santarelli M, Smeacetto F, Fiorilli S, Gondolini A, Mercadelli E, Sanson A, Brandon NPet al., 2016,

    Influence of the microstructure on the catalytic properties of SOFC anodes under dry reforming of methane

    , MATERIALS LETTERS, Vol: 164, Pages: 312-315, ISSN: 0167-577X

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