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  • Report
    Heptonstall PJ, Gross R, Steiner F, 2017,

    The costs and impacts of intermittency - 2016 update

    , London, Publisher: UK Energy Research Centre
  • Journal article
    Dong N, Prentice IC, Evans BJ, Caddy-Retalic S, Lowe AJ, Wright IJet al., 2017,

    Leaf nitrogen from first principles: field evidence for adaptive variation with climate

    , Biogeosciences, Vol: 14, Pages: 481-495, ISSN: 1726-4189

    Nitrogen content per unit leaf area (Narea) is a key variable in plant functional ecology and biogeochemistry. Narea comprises a structural component, which scales with leaf mass per area (LMA), and a metabolic component, which scales with Rubisco capacity. The co-ordination hypothesis, as implemented in LPJ and related global vegetation models, predicts that Rubisco capacity should be directly proportional to irradiance but should decrease with increases in ci : ca and temperature because the amount of Rubisco required to achieve a given assimilation rate declines with increases in both. We tested these predictions using LMA, leaf δ13C, and leaf N measurements on complete species assemblages sampled at sites on a north–south transect from tropical to temperate Australia. Partial effects of mean canopy irradiance, mean annual temperature, and ci : ca (from δ13C) on Narea were all significant and their directions and magnitudes were in line with predictions. Over 80 % of the variance in community-mean (ln) Narea was accounted for by these predictors plus LMA. Moreover, Narea could be decomposed into two components, one proportional to LMA (slightly steeper in N-fixers), and the other to Rubisco capacity as predicted by the co-ordination hypothesis. Trait gradient analysis revealed ci : ca to be perfectly plastic, while species turnover contributed about half the variation in LMA and Narea.

  • Journal article
    Kolster C, Mechleri E, Krevor S, Mac Dowell Net al., 2017,

    The role of CO<inf>2</inf> purification and transport networks in carbon capture and storage cost reduction

    , International Journal of Greenhouse Gas Control, Vol: 58, Pages: 127-141, ISSN: 1750-5836

    A number of Carbon Capture and Storage projects (CCS) are under way around the world, but the technology's high capital and operational costs act as a disincentive to large-scale deployment. In the case of both oxy-combustion and post-combustion CO 2 capture, the CO 2 compression and purification units (CO 2 CPU) are vital, but costly, process elements needed to bring the raw CO 2 product to a quality that is adequate for transport and storage. Four variants of the CO 2 CPU were modelled in Aspen HYSYS each of which provide different CO 2 product purities at different capital and operating costs. For each unit, a price of CO 2 is calculated by assuming that it is an independent entity in which to invest and the internal rate of return (IRR) must be greater or equal to the minimum rate of return on investment. In this study, we test the hypothesis that, owing to the fact that CO 2 will likely be transported in multi-source networks, not all CO 2 streams will need to be of high purity, and that it may be possible to combine several sources of varying purity to obtain an end-product that is suitable for storage. We find that, when considering study generated costs for an example network in the UK, optimally combining these different sources into one multi-source transport network subject to a minimum CO 2 purity of 96% can reduce the price of captured CO 2 by 17%.

  • Journal article
    Terrer C, Vicca S, Hungate BA, Phillips RP, Reich PB, Franklin O, Stocker BD, Fisher JB, Prentice ICet al., 2017,

    Response to Comment on "Mycorrhizal association as a primary control of the CO2 fertilization effect"

    , Science, Vol: 355, ISSN: 0036-8075

    Norby et al. center their critique on the design of the data set and the response variable used. We address these criticisms and reinforce the conclusion that plants that associate with ectomycorrhizal fungi exhibit larger biomass and growth responses to elevated CO2 compared with plants that associate with arbuscular mycorrhizae.

  • Journal article
    Few SPM, Gambhir A, Napp T, Hawkes A, Mangeon S, Bernie D, Lowe Jet al., 2017,

    The impact of shale gas on the cost and feasibility of meeting climate targets - a global energy system model analysis and an exploration of uncertainties

    , Energies, Vol: 10, ISSN: 1996-1073

    There exists considerable uncertainty over both shaleand conventional gas resource availability and extraction costs, as well as the fugitive methane emissions associated with shale gas extractionand its possible role in mitigating climate change. This study uses a multi-region energy system model, TIAM (TIMES Integrated Assessment Model),to consider the impact of a range of conventional and shale gas cost and availability assessments on mitigation scenariosaimed at achieving a limit to global warming of below 2°C in 2100, with a 50% likelihood. When adding shale gas to the global energy mix, the reduction to the global energy system cost is relatively small (up to0.4%), and the mitigation cost increases by 1-3% under all cost assumptions. The impact of a “dash for shale gas”, of unavailability of carbon capture and storage, of increased barriers to investment in low carbon technologies, and of higher than expectedleakage rates, are also considered;andare each found to have the potential to increase the cost and reduce feasibility of meeting globaltemperature goals. We concludethat the extraction of shale gas is not likely to significantly reduce the effort required to mitigate climate change under globallycoordinatedaction, but could increase required mitigation effort if not handled sufficiently carefully.

  • Journal article
    Coleman MA, Cetina-Heredia P, Roughan M, Feng M, van Sebille E, Kelaher BPet al., 2017,

    Anticipating changes to future connectivity within a network of marine protected areas

    , Global Change Biology, Vol: 23, Pages: 3533-3542, ISSN: 1365-2486

    Continental boundary currents are projected to be altered under future scenarios of climate change. As these currents often influence dispersal and connectivity among populations of many marine organisms, changes to boundary currents may have dramatic implications for population persistence. Networks of marine protected areas (MPAs) often aim to maintain connectivity, but anticipation of the scale and extent of climatic impacts on connectivity are required to achieve this critical conservation goal in a future of climate change. For two key marine species (kelp and sea urchins), we use oceanographic modelling to predict how continental boundary currents are likely to change connectivity among a network of MPAs spanning over 1000 km of coastline off the coast of eastern Australia. Overall change in predicted connectivity among pairs of MPAs within the network did not change significantly over and above temporal variation within climatic scenarios, highlighting the need for future studies to incorporate temporal variation in dispersal to robustly anticipate likely change. However, the intricacies of connectivity between different pairs of MPAs were noteworthy. For kelp, poleward connectivity among pairs of MPAs tended to increase in the future, whereas equatorward connectivity tended to decrease. In contrast, for sea urchins, connectivity among pairs of MPAs generally decreased in both directions. Self-seeding within higher-latitude MPAs tended to increase, and the role of low-latitude MPAs as a sink for urchins changed significantly in contrasting ways. These projected changes have the potential to alter important genetic parameters with implications for adaptation and ecosystem vulnerability to climate change. Considering such changes, in the context of managing and designing MPA networks, may ensure that conservation goals are achieved into the future.

  • Journal article
    Chen SS, Sun Y, Tsang DC, Graham NJ, Ok YS, Feng Y, Li XDet al., 2017,

    Insights into the subsurface transport of As(V) and Se(VI) in produced water from hydraulic fracturing using soil samples from Qingshankou Formation, Songliao Basin, China.

    , Environmental Pollution, Vol: 223, Pages: 449-456, ISSN: 1873-6424

    Produced water is a type of wastewater generated from hydraulic fracturing, which may pose a risk to the environment and humans due to its high ionic strength and the presence of elevated concentrations of metals/metalloids that exceed maximum contamination levels. The mobilization of As(V) and Se(VI) in produced water and selected soils from Qingshankou Formation in the Songliao Basin in China were investigated using column experiments and synthetic produced water whose quality was representative of waters arising at different times after well creation. Temporal effects of produced water on metal/metalloid transport and sorption/desorption were investigated by using HYDRUS-1D transport modelling. Rapid breakthrough and long tailings of As(V) and Se(VI) transport were observed in Day 1 and Day 14 solutions, but were reduced in Day 90 solution probably due to the elevated ionic strength. The influence of produced water on the hydrogeological conditions (i.e., change between equilibrium and non-equilibrium transport) was evidenced by the change of tracer breakthrough curves before and after the leaching of produced water. This possibly resulted from the sorption of polyacrylamide (PAM (-CH2CHCONH2-)n) onto soil surfaces, through its use as a friction reducer in fracturing solutions. The sorption was found to be reversible in this study. Minimal amounts of sorbed As(V) were desorbed whereas the majority of sorbed Se(VI) was readily leached out, to an extent which varied with the composition of the produced water. These results showed that the mobilization of As(V) and Se(VI) in soil largely depended on the solution pH and ionic strength. Understanding the differences in metal/metalloid transport in produced water is important for proper risk management.

  • Journal article
    Levontin P, Baranowski P, Leach AW, Bailey A, Mumford JD, Quetglas A, Kell LTet al., 2017,

    On the role of visualisation in fisheries management

    , Marine Policy, Vol: 78, Pages: 114-121, ISSN: 1872-9460

    Environmental change has focused the attention of scientists, policy makers and the wider public on the uncertainty inherent in interactions between people and the environment. Governance in fisheries is required to involve stakeholder participation and tobe more inclusive in its remit, which is no longer limited to ensuring a maximum sustainable yield from a single stock but considers species and habitat interactions, as well as social and economic issues. The increase in scope, complexity and awareness of uncertainty in fisheries management has brought methodological and institutional changes throughout the world. Progress towards comprehensive, explicit and participatory risk management in fisheries depends on effective communication. Graphic design and data visualisation have been underused in fisheries for communicating science to a wider range of stakeholders. In this paper, some of the general aspects of designing visualisations of modeling results are discussed and illustrated withexamples from the EU funded MYFISH project. These infographicswere tested in stakeholder workshops, and improved through feedbackfrom that 2process. It is desirable to convey not just modelling results but a sense of how reliable various models are. A survey was developed to judge reliability of different components of fisheries modelling: the quality of data, the quality of knowledge, model validation efforts, and robustness to key uncertainties. The results of these surveys were visualized for ten different models, and presented alongside the main case study.

  • Journal article
    Napp T, Bernie D, Thomas R, Lowe J, Hawkes A, Gambhir Aet al., 2017,

    Exploring the feasibility of low-carbon scenarios using historical energy transitions analysis

    , Energies, Vol: 10, ISSN: 1996-1073

    The scenarios generated by energy systems models provide a picture of the range of possible pathways to a low-carbon future. However, in order to be truly useful, these scenarios should not only be possible but also plausible. In this paper, we have used lessons from historical energy transitions to create a set of diagnostic tests to assess the feasibility of an example 2 °C scenario (generated using the least cost optimization model, TIAM-Grantham). The key assessment criteria included the rate of deployment of low carbon technologies and the rate of transition between primary energy resources. The rates of deployment of key low-carbon technologies were found to exceed the maximum historically observed rate of deployment of 20% per annum. When constraints were added to limit the scenario to within historically observed rates of change, the model no longer solved for 2 °C. Under these constraints, the lowest median 2100 temperature change for which a solution was found was about 2.1 °C and at more than double the cumulative cost of the unconstrained scenario. The analysis in this paper highlights the considerable challenge of meeting 2 °C, requiring rates of energy supply technology deployment and rates of declines in fossil fuels which are unprecedented.

  • Journal article
    Mechleri E, Brown S, Fennell PS, Mac Dowell Net al., 2017,

    CO2 capture and storage (CCS) cost reduction via infrastructure right-sizing

    , CHEMICAL ENGINEERING RESEARCH & DESIGN, Vol: 119, Pages: 130-139, ISSN: 0263-8762
  • Journal article
    Pedersen M, Andersen ZJ, Stafoggia M, Weinmayre G, Galassi C, Sorensen M, Eriksen KT, Tjonneland A, Loft S, Jaensch A, Nagel G, Concin H, Tsai M-Y, Grioni S, Marcon A, Krogh V, Riccerin F, Sacerdote C, Ranzi A, Sokhi R, Vermeulen R, de Hoogh K, Wang M, Beelen R, Vineis P, Brunekreef B, Hoek G, Raaschou-Nielsen Oet al., 2017,

    Ambient air pollution and primary liver cancer incidence in four European cohorts within the ESCAPE project

    , ENVIRONMENTAL RESEARCH, Vol: 154, Pages: 226-233, ISSN: 0013-9351
  • Journal article
    Gambhir A, Drouet L, McCollum D, Napp T, Bernie D, Hawkes A, Fricko O, Havlik P, Riahi K, Bosetti V, Lowe Jet al., 2017,

    Assessing the feasibility of global long-term mitigation scenarios

    , Energies, Vol: 10, ISSN: 1996-1073

    This study explores the critical notion of how feasible it is to achieve long-term mitigation goals to limit global temperature change. It uses a model inter-comparison of three integrated assessment models (TIAM-Grantham, MESSAGE-GLOBIOM and WITCH) harmonized for socio-economic growth drivers using one of the new shared socio-economic pathways (SSP2), to analyse multiple mitigation scenarios aimed at different temperature changes in 2100, in order to assess the model outputs against a range of indicators developed so as to systematically compare the feasibility across scenarios. These indicators include mitigation costs and carbon prices, rates of emissions reductions and energy efficiency improvements, rates of deployment of key low-carbon technologies, reliance on negative emissions, and stranding of power generation assets. The results highlight how much more challenging the 2OC goal is, when compared to the 2.5-4OC goals, across virtually all measures of feasibility. Any delay in mitigation or limitation in technology options also renders the 2OC goal much less feasible across the economic and technical dimensions explored. Finally, a sensitivity analysis indicates that aiming for less than 2OC is even less plausible, with significantly higher mitigation costs and faster carbon price increases, significantly faster decarbonization and zero-carbon technology deployment rates, earlier occurrence of very significant carbon capture and earlier onset of global net negative emissions. Such a systematic analysis allows a more in-depth consideration of what realistic level of long-term temperature changes can be achieved and what adaptation strategies are therefore required.

  • Journal article
    Romagnoli A, Vorraro G, Rajoo S, Copeland C, Martinez-Botas Ret al., 2017,

    Characterization of a supercharger as boosting & turbo-expansion device in sequential multi-stage systems

    , Energy Conversion and Management, Vol: 136, Pages: 127-141, ISSN: 0196-8904

    This paper proposes a detailed performance analysis and experimental characterization of a high-pressure supercharger in a multi-stage boosting system (turbo-super arrangement). Infact, besides the technical challenges associated with achieving adequate tuning, interoperability and driveability of multi-stage boosting systems, another challenge lies in their performance prediction during engine design. Indeed, performance maps of single boosting systems are usually provided by manufacturers and used as look-up tables in 1-D engine models. Tests are usually conducted in a standalone mode, with no information provided on the behaviour and performance of the combination of more than one boosting device. The supercharger was tested with varying inlet pressures and temperatures matching on-engine operating conditions and the results were then used to assess the effectiveness of 1-D engine models performance prediction when dealing with multi-stage boosting systems. An assessment on heat transfer in superchargers was also carried out together with the analysis on the nature of non-dimensional performance maps when dealing with a pressurized inlet. Finally, the analysis also looked into the opportunity to use the superchargers as expanders (‘expansion mode’) in order to cool the air charge entering the engine. The results showed that there is discrepancy between the efficiency values computed by 1-D engine models and those obtained experimentally under pressurized/heated inlet air conditions; the correction of the efficiency maps for heat transfer plays a significant role in the final measured efficiency and the correction of the maps for varying inlet temperatures must be carried out in order to avoid incurring in apparent efficiencies greater than unity. The experiments on the supercharger in ‘expansion mode’ showed that low isentropic efficiencies can be achieved; despite this, 1-D engine simulations showed that it is possible to achieve savings

  • Conference paper
    Latinopoulos C, Sivakumar A, Polak JW, 2017,

    Modeling electric vehicle charging behaviour: What is the relationship between charging location, driving distance and range anxiety?

    , Annual Meeting of the Transportation Research Board

    For parking operators and charging service providers it is critical to understand the factors that influence the demand for charging electric vehicles away from home. This information will not only help them to better anticipate the impact on the power grid, but also to develop revenue maximizing demand response strategies. Recent studies suggest that observable and unobservable attributes of travel demand affect the location and the frequency of charging events. Nevertheless, it is unlikely that there is a simple one way causality in the relationship, since the distinctive characteristics of electric vehicles might also lead to transformations in travel behaviour. In order to examine these ambiguous interrelationships we develop two models: a binary logistic regression for home charging vs out-of-home charging and an ordered logit regression for the daily distance driven with an electric vehicle. Attitudes and perceptions of individuals towards range constraints are indirectly captured with latent constructs like schedule flexibility or mobility necessity. The data used for the analysis were collected through the administration of an online survey to electric vehicle drivers in the UK and Ireland. Results show that there is an intrinsic link between charging and travel behaviour with potential implications both in a strategic and an operational level.

  • Journal article
    Pimentel R, Lopes DJH, Mexia AMM, Mumford JDet al., 2017,

    Seasonality of the Mediterranean Fruit Fly (Diptera: Tephritidae) on Terceira and Sao Jorge Islands, Azores, Portugal

    , Journal of Insect Science, Vol: 17, ISSN: 1536-2442

    Population dynamics studies are very important for any area-wide control program as they provide detailed knowledge about the relationship of Medfly [Ceratitis capitata (Wiedemann)] life cycle with host availability and abundance. The main goal of this study is to analyse seasonality of C. capitata in Terceira and Sao Jorge Islands (Azores archipelago) using field and laboratory data collected during (2010–2014) CABMEDMAC (MAC/3/A163) project. The results from Sao Jorge Island indicate significantly lower male/female ratio than on Terceira Island. This is an important finding specially regarding when stablishing the scenario parameters for a sterile insect technique application in each island. The population dynamics of C. capitata are generally linked with host fruit availability and abundance. However, on Terceira Island fruit infestation levels are not synchronized with the trap counts. For example, there was Medfly infestations in some fruits [e.g., Solanum mauritianum (Scop.)] while in the nearby traps there were no captures at the same time. From this perspective, it is important to denote the importance of wild invasive plants, on the population dynamics of C. capitata, as well important to consider the possibility of having different densities of traps according to the characteristics of each area in order to improve the network of traps surveillance’s sensitivity on Terceira Island.

  • Journal article
    Bhave A, Taylor RHS, Fennell P, Livingston WR, Shah N, Mac Dowell N, Dennis J, Kraft M, Pourkashanian M, Insa M, Jones J, Burdett N, Bauen A, Beal C, Smallbone A, Akroyd Jet al., 2017,

    Screening and techno-economic assessment of biomass-based power generation with CCS technologies to meet 2050 CO2 targets

    , APPLIED ENERGY, Vol: 190, Pages: 481-489, ISSN: 0306-2619

    Biomass-based power generation combined with CO2 capture and storage (Biopower CCS) currently represents one of the few practical and economic means of removing large quantities of CO2 from the atmosphere, and the only approach that involves the generation of electricity at the same time. We present the results of the Techno-Economic Study of Biomass to Power with CO2capture (TESBiC) project, that entailed desk-based review and analysis, process engineering, optimisation as well as primary data collection from some of the leading pilot demonstration plants. From the perspective of being able to deploy Biopower CCS by 2050, twenty-eight Biopower CCS technology combinations involving combustion or gasification of biomass (either dedicated or co-fired with coal) together with pre-, oxy- or post-combustion CO2 capture were identified and assessed. In addition to the capital and operating costs, techno-economic characteristics such as electrical efficiencies (LHV% basis), Levelised Cost of Electricity (LCOE), costs of CO2 captured and CO2 avoided were modelled over time assuming technology improvements from today to 2050. Many of the Biopower CCS technologies gave relatively similar techno-economic results when analysed at the same scale, with the plant scale (MWe) observed to be the principal driver of CAPEX (£/MWe) and the cofiring % (i.e. the weighted feedstock cost) a key driver of LCOE. The data collected during the TESBiC project also highlighted the lack of financial incentives for generation of electricity with negative CO2 emissions.

  • Journal article
    Raaschou-Nielsen O, Pedersen M, Stafoggia M, Weinmayr G, Andersen ZJ, Galassi C, Sommar J, Forsberg B, Olsson D, Oftedal B, Krog NH, Aasvang GM, Pyko A, Pershagen G, Korek M, De Faire U, Pedersen NL, OEstenson C-G, Fratiglioni L, Sorensen M, Eriksen KT, Tjonneland A, Peeters PH, Bueno-de-Mesquita HBA, Plusquin M, Key TJ, Jaensch A, Nagel G, Foeger B, Wang M, Tsai M-Y, Grioni S, Marcon A, Krogh V, Ricceri F, Sacerdote C, Migliore E, Tamayo I, Amiano P, Dorronsoro M, Sokhi R, Kooter I, de Hoogh K, Beelen R, Eeftens M, Vermeulen R, Vineis P, Brunekreef B, Hoek Get al., 2017,

    Outdoor air pollution and risk for kidney parenchyma cancer in 14 European cohorts

    , INTERNATIONAL JOURNAL OF CANCER, Vol: 140, Pages: 1528-1537, ISSN: 0020-7136

    Several studies have indicated weakly increased risk for kidney cancer among occupational groups exposed to gasoline vapors, engine exhaust, polycyclic aromatic hydrocarbons and other air pollutants, although not consistently. It was the aim to investigate possible associations between outdoor air pollution at the residence and the incidence of kidney parenchyma cancer in the general population. We used data from 14 European cohorts from the ESCAPE study. We geocoded and assessed air pollution concentrations at baseline addresses by land-use regression models for particulate matter (PM10, PM2.5, PMcoarse, PM2.5 absorbance (soot)) and nitrogen oxides (NO2, NOx), and collected data on traffic. We used Cox regression models with adjustment for potential confounders for cohort-specific analyses and random effects models for meta-analyses to calculate summary hazard ratios (HRs). The 289,002 cohort members contributed 4,111,908 person-years at risk. During follow-up (mean 14.2 years) 697 incident cancers of the kidney parenchyma were diagnosed. The meta-analyses showed higher HRs in association with higher PM concentration, e.g. HR = 1.57 (95%CI: 0.81–3.01) per 5 μg/m3 PM2.5 and HR = 1.36 (95%CI: 0.84–2.19) per 10−5m−1 PM2.5 absorbance, albeit never statistically significant. The HRs in association with nitrogen oxides and traffic density on the nearest street were slightly above one. Sensitivity analyses among participants who did not change residence during follow-up showed stronger associations, but none were statistically significant. Our study provides suggestive evidence that exposure to outdoor PM at the residence may be associated with higher risk for kidney parenchyma cancer; the results should be interpreted cautiously as associations may be due to chance.

  • Journal article
    Staffell IL, 2017,

    Measuring the progress and impacts of decarbonising British electricity

    , Energy Policy, Vol: 102, Pages: 463-475, ISSN: 1873-6777

    Britain’s ambitious carbon targets require that electricity be immediately and aggressively decarbonised, so it is reassuring to report that electricity sector emissions have fallen 46% in the three years to June 2016, their lowest since 1960. This paper analyses the factors behind this fall and the impacts they are having.The main drivers are: demand falling 1.3% per year due to efficiency gains and mild winters; gas doubling its share to 60% of fossil generation due to the carbon price floor; and the dramatic uptake of wind, solar and biomass which now supply up to 45% of demand. Accounting conventions also play their part: imported electricity and biomass would add 5% and 2% to emissions if they were included.The pace of decarbonisation is impressive, but raises both engineering and economic challenges. Falling peak demand has delayed fears of capacity shortage, but minimum net demand is instead becoming a problem. The headroom between inflexible nuclear and intermittent renewables is rapidly shrinking, with controllable output reaching a minimum of just 5.9 GW as solar output peaked at 7.1 GW. 2015 also saw Britain’s first negative power prices, the highest winter peak prices for six years, and the highest balancing costs.

  • Journal article
    Prentice IC, Cleator SF, Huang YH, Harrison SP, Roulstone Iet al., 2017,

    Reconstructing ice-age palaeoclimates: Quantifying low-CO2 effects on plants

    , Global and Planetary Change, Vol: 149, Pages: 166-176, ISSN: 0921-8181

    We present a novel method to quantify the ecophysiological effects of changes in CO2 concentration during the reconstruction of climate changes from fossil pollen assemblages. The method does not depend on any particular vegetation model. Instead, it makes use of general equations from ecophysiology and hydrology that link moisture index (MI) to transpiration and the ratio of leaf-internal to ambient CO2 (χ). Statistically reconstructed MI values are corrected post facto for effects of CO2 concentration. The correction is based on the principle that e, the rate of water loss per unit carbon gain, should be inversely related to effective moisture availability as sensed by plants. The method involves solving a non-linear equation that relates e to MI, temperature and CO2 concentration via the Fu-Zhang relation between evapotranspiration and MI, Monteith's empirical relationship between vapour pressure deficit and evapotranspiration, and recently developed theory that predicts the response of χ to vapour pressure deficit and temperature. The solution to this equation provides a correction term for MI. The numerical value of the correction depends on the reconstructed MI. It is slightly sensitive to temperature, but primarily sensitive to CO2 concentration. Under low LGM CO2 concentration the correction is always positive, implying that LGM climate was wetter than it would seem from vegetation composition. A statistical reconstruction of last glacial maximum (LGM, 21±1 kyr BP) palaeoclimates, based on a new compilation of modern and LGM pollen assemblage data from Australia, is used to illustrate the method in practice. Applying the correction brings pollen-reconstructed LGM moisture availability in southeastern Australia better into line with palaeohydrological estimates of LGM climate.

  • Book chapter
    Clarke CJ, Tu WC, Weigand L, Brandt A, Hallett JPet al., 2017,

    Solvation behavior of ionic liquids and their role in the production of lignocellulosic biofuels and sustainable chemical feedstocks

    , Advanced Green Chemistry: Part 1: Greener Organic Reactions and Processes, Pages: 77-134, ISBN: 9789813228108
  • Journal article
    Green RJ, Pudjianto D, Staffell I, Strbac Get al., 2016,

    Market Design for Long-Distance Trade in Renewable Electricity

    , Energy Journal, Vol: 37, Pages: 5-22, ISSN: 0195-6574

    While the 2009 EU Renewables Directive allows countries to purchase some of their obligation fromanother member state, no country has yet done so, preferring to invest locally even where load factors arevery low. If countries specialised in renewables most suited to their own endowments and expandedinternational trade, we estimate that system costs in 2030 could be reduced by 5%, or €15 billion a year,after allowing for the costs of extra transmission capacity, peaking generation and balancing operationsneeded to maintain electrical feasibility.Significant barriers must be overcome to unlock these savings. Countries that produce more renewablepower should be compensated for the extra cost through tradable certificates, while those that buy fromabroad will want to know that the power can be imported when needed. Financial Transmission Rightscould offer companies investing abroad confidence that the power can be delivered to their consumers.They would hedge short-term fluctuations in prices and operate much more flexibly than the existingsystem of physical point-to-point rights on interconnectors. Using FTRs to generate revenue fortransmission expansion could produce perverse incentives to under-invest and raise their prices, sorevenues from FTRs should instead be offset against payments under the existing ENTSO-Ecompensation scheme for transit flows. FTRs could also facilitate cross-border participation in capacitymarkets, which are likely to be needed to reduce risks for the extra peaking plants required.

  • Report
    Hanna RF, Gross R, Parrish B, 2016,

    Best practice in heat decarbonisation policy: A review of the international experience of policies to promote the uptake of low-carbon heat supply

    This evidence review evaluates the effectiveness of different policy approaches to support heat supply or infrastructure transitions internationally. Focusing on heat pump deployment and the roll out of district heating, the research identifies lessons from the international policy experience and assess how relevant these might be to the UK context. The report explores the role of different policies – including regulation, fiscal policies, incentives, planning policy and of different models of governance. It also considers historical and contextual factors such as ownership structures, resource endowments and energy prices. The review was undertaken by the UKERC Technology and Policy Assessment team in response to widespread stakeholder interest in policies related to the decarbonisation of heat. It informs the Committee on Climate Change review of heat decarbonisation and seeks to inform the UK Government’s heat strategy, forthcoming in 2017. The main aim of the research is to review and evaluate policies and policy packages used to bring about a substantial change in the technologies and infrastructures used to provide space heating and hot water for homes and businesses. The key question that this TPA project therefore asked is: What policies and other factors have driven change/transformation in heat delivery technologies, fuels and infrastructure?

  • Journal article
    Vitolo C, Wells P, Dobias M, Buytaert Wet al., 2016,

    fuse: An R package for ensemble Hydrological Modelling

    , The Journal of Open Source Software, Vol: 1, Pages: 52-52
  • Journal article
    Bertei A, Tariq F, Yufit V, Ruiz Trejo E, Brandon Net al., 2016,

    Guidelines for the rational design and engineering of 3D manufactured solid oxide fuel cell composite electrodes

    , Journal of the Electrochemical Society, Vol: 164, Pages: F89-F98, ISSN: 0013-4651

    The growth of 3D printing has opened the scope for designing microstructures for solid oxide fuel cells(SOFCs) with improved power density and lifetime. This technique can introduce structural modifications at a scale larger than particle size but smaller than cell size, such as by insertingelectrolyte pillars of ~5-100 µm. This study sets the minimum requirements for the rational design of 3D printedelectrodes based on an electrochemical model and analytical solutions for functional layers with negligible electronic resistanceand no mixed conduction. Results show that this structural modification enhances the power density when the ratio keffbetween effective conductivity and bulk conductivity of the ionic phase is smaller than 0.5. The maximum performance improvement is predicted as a function of keff. A design study on a wide range of pillar shapes indicates that improvements are achieved by any structural modification which provides ionic conduction up to a characteristic thickness ~10-40 µm without removing active volume at the electrolyte interface. The best performance is reached for thin (< ~2 µm) and long (> ~80 µm) pillars when the compositeelectrode is optimised for maximum three-phase boundarydensity, pointing towards the design of scaffolds with well-defined geometry and fractal structures.

  • Journal article
    Siegert MJ, 2016,

    Vulnerable Antarctic ice shelves

    , Nature Climate Change, Vol: 7, Pages: 11-12, ISSN: 1758-6798

    Standfirst: The decay of floating ice shelves around Antarctica speeds up ice flow from the continent and enhances sea-level rise. Now meltwater attributed to warm winds has been discovered on an East Antarctic ice shelf, suggesting greater vulnerability than previously thought.

  • Journal article
    Zekri S, Madani K, Bazargan-Lari MR, Kotagama H, Kalbus Eet al., 2016,

    Feasibility of adopting smart water meters in aquifer management: An integrated hydro-economic analysis

    , AGRICULTURAL WATER MANAGEMENT, Vol: 181, Pages: 85-93, ISSN: 0378-3774
  • Journal article
    Muniina K, Maksimovic C, Graham N, 2016,

    A novel approach for estimating urban water end use characteristics of cities in the developing world

    , Urban Water Journal, Vol: 14, Pages: 750-757, ISSN: 1573-062X

    The design of alternative urban water supply interventions for a community located in a low-income country requires detailed and precise knowledge of the nature, frequency and intensity of various characteristic water end-uses in the community. Without the availability of this characteristic water use information, high resolution metering experiments are the usually preferred methods to measure the water use volumes. However, in the developing world, these high resolution experiments are not an available option. Leaving the imprecise household interviewing process of data collection as the only option. This paper presents a novel methodology that improves and expands on the socially collected water uses data, through the use of a stochastic modelling process of the water use volumes to estimate the total monthly water use of the community. The methodology not only improves the estimates of water use volumes but also provides a mathematical modelling description of the household water uses in the community.

  • Journal article
    Ezzati M, Baumgartner JC, 2016,

    Household energy and health: where next for research and practice?

    , Lancet, Vol: 389, Pages: 130-132, ISSN: 0140-6736
  • Journal article
    Madani K, AghaKouchak A, Mirchi A, 2016,

    Iran’s socio-economic drought: challenges of a water-bankrupt nation

    , Iranian Studies, Vol: 49, Pages: 997-1016, ISSN: 1475-4819

    Iran is currently experiencing serious water problems. Frequent droughts coupled with over-abstraction of surface and groundwater through a large network of hydraulic infrastructure and deep wells have escalated the nation’s water situation to a critical level. This is evidenced by drying lakes, rivers and wetlands, declining groundwater levels, land subsidence, water quality degradation, soil erosion, desertification and more frequent dust storms. This paper overviews the major drivers of Iran’s water problems. It is argued that while climatic changes and economic sanctions are commonly blamed as the main drivers of water problems, Iran is mainly suffering from a socio-economic drought—i.e. “water bankruptcy,” where water demand exceeds the natural water supply. In theory, this problem can be resolved by re-establishing the balance between water supply and demand through developing additional sources of water supply and implementing aggressive water demand reduction plans. Nevertheless, the current structure of the water governance system in Iran and the absence of a comprehensive understanding of the root causes of the problem leave minimal hope of developing sustainable solutions to Iran’s unprecedented water problems.

  • Journal article
    Parkes MA, Tompsett DA, d'Avezac M, Offer GJ, Brandon NP, Harrison NMet al., 2016,

    The atomistic structure of yttria stabilised zirconia at 6.7 mol%: an ab initio study.

    , Physical Chemistry Chemical Physics, Vol: 18, Pages: 31277-31285, ISSN: 1463-9084

    Yttria stabilized zirconia (YSZ) is an important oxide ion conductor used in solid oxide fuel cells, oxygen sensing devices, and for oxygen separation. Doping pure zirconia (ZrO2) with yttria (Y2O3) stabilizes the cubic structure against phonon induced distortions and this facilitates high oxide ion conductivity. The local atomic structure of the dopant is, however, not fully understood. X-ray and neutron diffraction experiments have established that, for dopant concentrations below 40 mol% Y2O3, no long range order is established. A variety of local structures have been suggested on the basis of theoretical and computational models of dopant energetics. These studies have been restricted by the difficulty of establishing force field models with predictive accuracy or exploring the large space of dopant configurations with first principles theory. In the current study a comprehensive search for all symmetry independent configurations (2857 candidates) is performed for 6.7 mol% YSZ modelled in a 2 × 2 × 2 periodic supercell using gradient corrected density functional theory. The lowest energy dopant structures are found to have oxygen vacancy pairs preferentially aligned along the ⟨210⟩ crystallographic direction in contrast to previous results which have suggested that orientation along the ⟨111⟩ orientation is favourable. Analysis of the defect structures suggests that the Y(3+)-Ovac interatomic separation is an important parameter for determining the relative configurational energies. Current force field models are found to be poor predictors of the lowest energy structures. It is suggested that the energies from a simple point charge model evaluated at unrelaxed geometries is actually a better descriptor of the energy ordering of dopant structures. Using these observations a pragmatic procedure for identifying low energy structures in more complicated material models is suggested. Calculation of the oxygen vacancy migration activat

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