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Van Vliet M.T.H.,Wageningen University | Van Vliet M.T.H.,International Institute For Applied Systems Analysis | Vogele S.,Julich Research Center | Rubbelke D.,Basque Center for Climate Change | Rubbelke D.,Ikerbasque
Environmental Research Letters | Year: 2013

Recent warm, dry summers showed the vulnerability of the European power sector to low water availability and high river temperatures. Climate change is likely to impact electricity supply, in terms of both water availability for hydropower generation and cooling water usage for thermoelectric power production. Here, we show the impacts of climate change and changes in water availability and water temperature on European electricity production and prices. Using simulations of daily river flows and water temperatures under future climate (2031-2060) in power production models, we show declines in both thermoelectric and hydropower generating potential for most parts of Europe, except for the most northern countries. Based on changes in power production potentials, we assess the cost-optimal use of power plants for each European country by taking electricity import and export constraints into account. Higher wholesale prices are projected on a mean annual basis for most European countries (except for Sweden and Norway), with strongest increases for Slovenia (12-15%), Bulgaria (21-23%) and Romania (31-32% for 2031-2060), where limitations in water availability mainly affect power plants with low production costs. Considering the long design life of power plant infrastructures, short-term adaptation strategies are highly recommended to prevent undesired distributional and allocative effects. © 2013 IOP Publishing Ltd.

Cosenza A.,University of Palermo | Mannina G.,University of Palermo | Vanrolleghem P.A.,Laval University | Neumann M.B.,Laval University | And 2 more authors.
Environmental Modelling and Software | Year: 2013

Three global sensitivity analysis (GSA) methods are applied and compared to assess the most relevant processes occurring in wastewater treatment systems. In particular, the Standardised Regression Coefficients, Morris Screening and Extended-FAST methods are applied to a complex integrated membrane bioreactor (MBR) model considering 21 model outputs and 79 model factors. The three methods are applied with numerical settings as suggested in literature. The main objective considered is to classify important factors (factors prioritisation) as well as non-influential factors (factors fixing). The performance is assessed by comparing the most reliable method (Extended-FAST), by means of proposed criteria, with the two other methods. In particular, similarity to results obtained from Extended-FAST is assessed for sensitivity indices, for the ranking of sensitivity indices, for the classification into important/non-influential factors and for the method's ability to detect interaction among factors and to provide results in a reasonable time.It was found that the computationally less expensive SRC method was applied outside its range of applicability (R2)=(0.3-0.6)<0.7. Still, the SRC produced a ranking of important factors similar to Extended-FAST. For some variables significant interactions among the factors were revealed by computing the total effect indices STi using Extended-FAST. This means that to obtain reliable variance decomposition and to detect and quantify interactions among the factors, the use of the Extended-FAST is recommended. Regarding the comparison between Morris screening and Extended-FAST a poor agreement was found. In particular, the Morris screening overestimated the number of both important and non-influential factors compared to Extended-FAST for the analysed case study. © 2013 Elsevier Ltd.

Gamerith V.,University of Graz | Neumann M.B.,Laval University | Neumann M.B.,Basque Center for Climate Change | Neumann M.B.,Ikerbasque | And 2 more authors.
Water Research | Year: 2013

While several approaches for global sensitivity analysis (GSA) have been proposed in literature, only few applications exist in urban drainage modelling. This contribution discusses two GSA methods applied to a sewer flow and sewer water quality model: Standardised Regression Coefficients (SRCs) using Monte-Carlo simulation as well as the Morris Screening method. For selected model variables we evaluate how the sensitivities are influenced by the choice of the rainfall event. The aims are to i) compare both methods concerning the similarity of results and their applicability, ii) discuss the implications for factor fixing (identifying non-influential parameters) and factor prioritisation (identifying important parameters) and iii) rank the important parameters for the investigated model. It was shown that both methods lead to similar results for the hydraulic model. Parameter interactions and non-linearity were identified for the water quality model and the parameter ranking differs between the methods. For the investigated model the results allow a sound choice of output variables and rainfall events in view of detailed uncertainty analysis or model calibration. We advocate the simultaneous use of both methods for a first model assessment as they allow answering both factor fixing and factor prioritisation at low computational cost. © 2013 Elsevier Ltd.

Krishna V.V.,University of Gottingen | Drucker A.G.,Bioversity International | Pascual U.,University of Cambridge | Pascual U.,Basque Center for Climate Change | And 2 more authors.
Ecological Economics | Year: 2013

This paper examines the role of direct compensation payments for agrobiodiversity conservation, using minor millet landraces in India as an example. The cost of farmer participation in a hypothetical 'payments for agrobiodiversity conservation services' (PACS) scheme is estimated using a stated preference valuation approach. Significant inter-crop and inter-varietal differences are observed with respect to consumption values, upon which the compensation demanded by farm households is shown to primarily depend. Drawing on a categorisation of consumption values and farmer preferences, the paper points to the importance of simultaneously considering a range of potential interventions in order to conserve a priority portfolio of agrobiodiverse resources in predominantly subsistence-based agricultural systems. © 2012 Elsevier B.V.

Markandya A.,Basque Center for Climate Change | Markandya A.,University of Bath | Pemberton M.,University College London
Energy Policy | Year: 2010

The paper develops a framework to analyze energy security in an expected utility framework, where there is a risk of disruption of imported energy. The analysis shows the importance of an energy tax as a tool in maximizing expected utility, and how the level of that tax varies according to the key parameters of the system: risk aversion, probability of disruption, demand elasticity and cost of disruption. © 2009 Elsevier Ltd. All rights reserved.

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