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Major transformation of the global energy system is required for climate change mitigation. However, energy demand patterns and supply systems are themselves subject to climate change impacts. These impacts will variously help and hinder mitigation and adaptation efforts, so it is vital they are well understood and incorporated into models used to study energy system decarbonisation pathways. To assess the current state of understanding of this topic and identify research priorities, this paper critically reviews the literature on the impacts of climate change on the energy supply system, summarising the regional coverage of studies, trends in their results and sources of disagreement. We then examine the ways in which these impacts have been represented in integrated assessment models of the electricity or energy system.Studies tend to agree broadly on impacts for wind, solar and thermal power stations. Projections for impacts on hydropower and bioenergy resources are more varied. Key uncertainties and gaps remain due to the variation between climate projections, modelling limitations and the regional bias of research interests. Priorities for future research include the following: further regional impact studies for developing countries; studies examining impacts of the changing variability of renewable resources, extreme weather events and combined hazards; inclusion of multiple climate feedback mechanisms in IAMs, accounting for adaptation options and climate model uncertainty. 相似文献
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The study presented herein concerns the double-layer repulsive force that exists between clay particles in a clay–water–electrolyte system. The objective is to examine the nature of the double-layer repulsive force between two negatively charged clay particles that are inclined to each other and have finite length. The finite element numerical technique is used first to determine the spatial distribution of the electric potential. The net repulsive force and its location are then evaluated from this known distribution of the potential on the basis of the theory of electrostatics. A systematic parametric study is performed by varying certain dimensionless system variables, particularly to investigate the effect of orientation, surface potential and particle length. It is found that for non-parallel orientation, as the value of inclination and surface potential increase, the repulsive force decreases and its location shifts towards the particle ends that are closer to each other. 相似文献
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A non-linear optimization technique based on the quasi-Newton approach is employed to back-calculate certain model parameters of a simple, bounding surface, soil plasticity model from in situ pressuremeter data. The theoretical response corresponding to a given set of parameters is generated by finite element analysis. A semi-analytical procedure is developed for the accurate and efficient evaluation of the gradient of objective function with respect to the model parameters of interest. The BFGS update is used to update the Hessian. Results of a series of numerical experimentation using artificial pressuremeter responses is first reported and discussed. A set of laboratory cavity expansion data is then used to calibrate the constitutive model. 相似文献
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Calibration of dynamic analysis methods from field test data 总被引：3，自引：0，他引：3
In view of the heterogeneity of natural soil deposits and approximations made in analysis methods, in situ methods of determining soil parameters are highly desirable. The problem of interest here is the nonlinear dynamic behavior of pile foundations. It is shown in this paper that soil parameters needed for simplified dynamic analysis of a single pile may be back-calculated from the dynamic response of the pile measured in the field. A pile was excited by applying a large horizontal dynamic force at the pile-head level, and the response measured. In this paper, two different (simplified) methods of modeling the dynamic response of the pile are considered. One of the methods is based on the Winkler foundation approach, with the spring constant characterized by the so-called nonlinear p–y springs. The second method is based on the equivalent-linear finite element approach, with the nonlinearity of shear modulus and damping accounted for by employing the so-called degradation relationships. In the latter, the effect of interface nonlinearity is also considered. Starting with best estimates of soil parameters, the experimental data on the response of pile is used to fine-tune the values of the parameters, and thereby, to estimate parameters that are representative of in situ soil conditions. 相似文献
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Steve Pye Christophe McGlade Chris Bataille Gabrial Anandarajah Amandine Denis-Ryan Vladimir Potashnikov 《Climate Policy》2016,16(4):S92-S109
The role of fossils fuels in national economies will change radically over the next 40 years under a strong climate regime. However, capturing this changing role through national-based analyses is challenging due to the global nature of fossil fuel demand and resulting trade patterns. This article sets out the limitations of existing national-scale decarbonization analyses in adequately capturing global conditions and explores how the introduction of a global modelling framework could provide vital insights, particularly for those countries that are dependent on fossil fuel exports or imports.The article shows that fossil fuel use will significantly decline by 2050, although gas will have an important transition role. This leaves large fossil fuel exporters exposed, the extent of which is determined by mitigation action in different regions and especially by the pathways adopted by the larger Asian economies. We find that global-scale models provide critical insights that complement the more detailed national analyses and should play a stronger role in informing deep decarbonization pathways (DDPs). They also provide an important basis for exploring key uncertainties around technology uptake, mitigation rates and how this plays out in the demand for fossil fuels. However, use of global models also calls for improved representation of country specifics in global models, which can oversimplify national economic and political realities. Using both model scales provides important insights that are complementary but that can challenge the other’s orthodoxy. However, neither can replace the other’s strengths.Policy relevance:In recent years, how global fossil fuel markets will evolve under different climate regimes has been subject to much debate and analysis. This debate includes whether investments in fossil fuel production still make sense or will be exposed in the future to liabilities associated with high carbon prices. This is important for governments who need to develop coherent policy in relation to fossil fuel sectors and their role as drivers of economic growth and in providing for domestic energy needs. This article argues that national analyses need to be fully cognizant of the global-scale transition, which can be informed by using a multi-scale modelling approach. 相似文献
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A. Anandarajah 《Engineering Geology》1997,47(4):491-323
In an assembly of clay particles placed in a fluid, each particle is typically subjected to: (1) double-layer repulsive forces; (2) van der Waals attractive forces; and (3) contact mechanical forces. The study presented here concerns an approximate, quantitative analysis of clay suspensions, with considerations to the first two - the physico-chemical forces. Using recent theories to calculate the physico-chemical forces between two clay particles in an approximate model of an assembly, the equilibrium void ratio of a clay suspension is computed. The mechanical forces are ignored in the analysis. The results serve to verify the validity of physico-chemical theories employed and help interpret experimental data more fundamentally in terms of the system variables. 相似文献
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