Suchergebnisse

One hundred and ninety-three governments adopted the Paris Agreement on Climate Change in 2015. The agreement foresees, for the near term, a new bottom-up process where countries pledge so-called nationally determined contributions (NDCs) for reducing their greenhouse gas (GHG) emissions by 2025–2030. At the same time, the Paris Agreement defines the longterm objective to hold temperature change to well below 2 °C and to pursue efforts to limit it further to 1.5 °C. The consistency between the NDCs and the long-term temperature goals is planned to be regularly assessed in global stocktaking exercises as part of the international negotiations. At the same time, countries have also committed themselves to implement a set of Sustainable Development Goals (SDGs) in order to eradicate poverty, protect the global environment and spur inclusive economic development. Within this context, the CD-LINKS project (www.cd-links.org) brought together an international team of researchers with global, national and sectoral expertise to explore possible linkages between national and global pathways consistent with the overall objective of the Paris Agreement and sustainable development. Part of this work is summarised in this special issue in Climatic Change, which contains eleven papers, including this introductory one, presenting the insights from the collaboration between national and global modelling teams and yielding a more coherent and detailed picture of the future than is typical of climate change mitigation pathways studies focusing on the global level only.

One hundred and ninety-three governments adopted the Paris Agreement on Climate Change in 2015. The agreement foresees, for the near term, a new bottom-up process where countries pledge so-called nationally determined contributions (NDCs) for reducing their greenhouse gas (GHG) emissions by 2025–2030. At the same time, the Paris Agreement defines the longterm objective to hold temperature change to well below 2 °C and to pursue efforts to limit it further to 1.5 °C. The consistency between the NDCs and the long-term temperature goals is planned to be regularly assessed in global stocktaking exercises as part of the international negotiations. At the same time, countries have also committed themselves to implement a set of Sustainable Development Goals (SDGs) in order to eradicate poverty, protect the global environment and spur inclusive economic development. Within this context, the CD-LINKS project (www.cd-links.org) brought together an international team of researchers with global, national and sectoral expertise to explore possible linkages between national and global pathways consistent with the overall objective of the Paris Agreement and sustainable development. Part of this work is summarised in this special issue in Climatic Change, which contains eleven papers, including this introductory one, presenting the insights from the collaboration between national and global modelling teams and yielding a more coherent and detailed picture of the future than is typical of climate change mitigation pathways studies focusing on the global level only.

This work seeks to evaluate overnight construction costs (OCC) and lead-time escalation of nuclear power construction projects from 1955 to 2016. To this end, a comprehensive database of commercial Light Water Reactors (LWR) was developed and a statistical analysis was conducted. Findings reveal a significant delay in lead-time, especially for the last generation reactors constructed from 2010s, with 3/4 of the sample showing significant construction delays. This results in an escalation of capital costs rather than in a decline. Average OCC of newer reactors is 60% higher than the ones implemented in the earlier stages of the nuclear era. This suggests a discontinuity of the learning curve for both OCC and lead-time, which threats the market and financial sustainability of current and future nuclear energy projects. Although this is a general trend, this discontinuity is country specific and, thus, induced by national policies and regulatory frameworks. Therefore, the role of nuclear technology as an alternative to cope with the need for a decarbonisation of the power sector must be better evaluated, taking into account the real cost impacts of nuclear technology implementation. ; - This work was funded by the Brazilian National Council for Scientific and Technological Development agency (CNPq) (166074/2015-2) and the Marie Curie International Research Staff Exchange Scheme Fellowship within the 7th European Union Framework Programme, under the project NETEP- European Brazilian Network on Energy Planning (PIRSES-GA-2013-612263). Authors would like to acknowledge Rafael Garaffa for his helpful advices about processing data with R statistical software and data analysis. Authors are also thankful to the comments of anonymous reviewers. Special thanks to the Grantham Institute and Imperial College London media office for assisting in publicising the findings of the ...

Air Conditioning (AC) appliances are a highly effective adaptation strategy to rising temperatures, thus making future climate conditions an important driver of space cooling energy demand. The main goal of this study is to assess the impacts of climate change on Cooling Degree Days computed with wet-bulb temperature (CDDwb) and household space cooling demand in Brazil. We compare the needs under three specific warming levels (SWLs) scenarios (1.5 °C, 2 °C and 4 °C) to a baseline with historically observed meteorological parameters by combining CDDwb projections with an end-use model to evaluate the energy requirements of air conditioning. The effects of the climate change were isolated, and no future expansion in AC ownership considered. Carbon dioxide (CO2) emissions associated with AC energy demand are also calculated. Results show an increase in both average CDDwb and AC electricity consumption for the global warming scenarios in all Brazilian regions. The Northern region shows the highest increase in CDDwb (187% in CDDwb for SWL 4 °C), while the Southeast presents the highest AC energy consumption response (326% in the AC energy consumption for SWL 4 °C) compared to the baseline. At the national level, CDDwb and the AC energy consumption in all SWLs scenarios grow by 70%, 99% and 190%, respectively.

The Brazilian power generation sector faces a paradigm change driven by, on one hand, a shift from a hydropower dominated mix and, on the other hand, international goals for reducing greenhouse gas emissions. The objective of this work is to evaluate five scenarios for the Brazilian power sector until 2050 using a multi-criteria decision analysis tool. These scenarios include a baseline trend and low carbon policy scenarios based on carbon taxes and carbon emission limits. To support the applied methodology, a questionnaire was elaborated to integrate the perceptions of experts on the scenario evaluation process. Considering the results from multi-criteria analysis, scenario preference followed the order of increasing share of renewables in the power sector. The preferable option for the future Brazilian power sector is a scenario where wind and biomass have a major contribution. The robustness of the multi-criteria tool applied in this study was tested by a sensitivity analysis. This analysis demonstrated that, regardless of the respondents' preferences and backgrounds, scenarios with higher shares of fossil fuel sources are the least preferable option, while scenarios with major contributions from wind and biomass are the preferable option to supply electricity in Brazil through 2050. ; The research that allowed the publication of this paper has been produced with the financial assistance of the European Union in the context of the CLIMACAP project (EuropeAid/131944/C/SER/Multi) and of the U.S. Agency for International Development and U.S. Environmental Protection Agency in the context of the LAMP project (under Interagency Agreements DW89923040 and DW89923951US). The contents of this publication are the sole responsibility of the authors and can in no way be taken to reflect the views of the European Union or the U.S. government. The authors would like to thank the feedback and efforts from all CLIMACAP and LAMP project partners for enabling the research results reported in this article. This research was ...

This is the final version. Available from IOP Publishing via the DOI in this record. ; No new data were created or analysed in this study. ; Integrated assessment models (IAMs) have emerged as key tools for building and assessing long term climate mitigation scenarios. Due to their central role in the recent IPCC assessments, and international climate policy analyses more generally, and the high uncertainties related to future projections, IAMs have been critically assessed by scholars from different fields receiving various critiques ranging from adequacy of their methods to how their results are used and communicated. Although IAMs are conceptually diverse and evolved in very different directions, they tend to be criticised under the umbrella of 'IAMs'. Here we first briefly summarise the IAM landscape and how models differ from each other. We then proceed to discuss six prominent critiques emerging from the recent literature, reflect and respond to them in the light of IAM diversity and ongoing work and suggest ways forward. The six critiques relate to (a) representation of heterogeneous actors in the models, (b) modelling of technology diffusion and dynamics, (c) representation of capital markets, (d) energy-economy feedbacks, (e) policy scenarios, and (f) interpretation and use of model results. ; European Union Horizon 2020

The Working Group III (WGIII) contribution to the IPCC's Fifth Assessment Report (AR5) assesses literature on the scientific, technological, environmental, economic and social aspects of mitigation of climate change. It builds upon the WGIII contribution to the IPCC's Fourth Assessment Report (AR4), the Special Report on Renewable Energy Sources and Climate Change Mitigation (SRREN) and previous reports and incorporates subsequent new findings and research. Throughout, the focus is on the implications of its findings for policy, without being prescriptive about the particular policies that governments and other important participants in the policy process should adopt. In light of the IPCC's mandate, authors in WGIII were guided by several principles when assembling this assessment: (1) to be explicit about mitigation options, (2) to be explicit about their costs and about their risks and opportunities vis-a-vis other development priorities, (3) and to be explicit about the underlying criteria, concepts, and methods for evaluating alternative policies. This summary offers the main findings of the report.

The Working Group III (WGIII) contribution to the IPCC's Fifth Assessment Report (AR5) assesses literature on the scientific, technological, environmental, economic and social aspects of mitigation of climate change. It builds upon the WGIII contribution to the IPCC's Fourth Assessment Report (AR4), the Special Report on Renewable Energy Sources and Climate Change Mitigation (SRREN) and previous reports and incorporates subsequent new findings and research. Throughout, the focus is on the implications of its findings for policy, without being prescriptive about the particular policies that governments and other important participants in the policy process should adopt. In light of the IPCC's mandate, authors in WGIII were guided by several principles when assembling this assessment: (1) to be explicit about mitigation options, (2) to be explicit about their costs and about their risks and opportunities vis-a-vis other development priorities, (3) and to be explicit about the underlying criteria, concepts, and methods for evaluating alternative policies. This summary offers the main findings of the report.