National Policy Makers

This Summary for Policymakers presents key findings from the Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX). The SREX approaches the topic by assessing the scientific literature on issues that range from the relationship between climate change and extreme weather and climate events (‘climate extremes’) to the implications of these events for society and sustainable development. The assessment concerns the interaction of climatic, environmental, and human factors that can lead to impacts and disasters, options for managing the risks posed by impacts and disasters, and the important role that non-climatic factors play in determining impacts.

This introductory chapter serves as a lead-in to the science presented in the Working Group I (WGI) contribution to the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). Chapter 1 in the IPCC Fourth Assessment Report (AR4) (Le Treut et al., 2007) provided a historical perspective on the understanding of climate science and the evidence regarding human influence on the Earth’s climate system. Since the last assessment, the scientific knowledge gained through observations, theoretical analyses, and modelling studies has continued to increase and to strengthen further the evidence linking human activities to the ongoing climate change. In AR5, Chapter 1 focuses on the concepts and definitions applied in the discussions of new findings in the other chapters. It also examines several of the key indicators for a changing climate and shows how the current knowledge of those indicators compares with the projections made in previous assessments. The new scenarios for projected human-related emissions used in this assessment are also introduced. Finally, the chapter discusses the directions and capabilities of current climate science, while the detailed discussion of new findings is covered in the remainder of the WGI contribution to the AR5.

List of the Expert Reviewers of the IPCC WGI Fifth Assessment Report.

List of contributors to the IPCC WGI Fifth Assessment Report.

List of Acronyms used in the Fifth IPCC Assessment Report (AR5).

This glossary defines some specific terms as the Lead Authors intend them to be interpreted in the context of this report.

Annex II presents, in tabulated form, data related to historical and projected changes in the climate system that are assessed in the chapters of this report (see Section 1.6). It also includes some comparisons with the Third Assessment Report (TAR) and Fourth Assessment Report (AR4) results. These data include values for emissions into the atmosphere, atmospheric abundances and burdens (integrated abundance), effective radiative forcing (ERF; includes adjusted forcing from aerosols, see Chapters 7 and 8), and global mean surface temperatures and sea level. Projections from 2010 to 2100 focus on the RCP scenarios (Moss et al., 2010; Lamarque et al., 2010; 2011; Meinshausen et al., 2011a; van Vuuren et al., 2011; see also Chapters 1, 6, 8, 11, 12 and 13). Projections also include previous IPCC scenarios (IPCC Scenarios 1992a (IS92a), Special Report on Emission Scenarios (SRES) A2 and B1, TAR Appendix II) and some alternative near-term scenarios for methane (CH4) and short-lived pollutants that impact climate or air quality. Emissions from biomass burning are included as anthropogenic. ERF from land use change is also included in some tables.

This Annex presents a series of figures showing global and regional patterns of climate change computed from global climate model output gathered as part of the Coupled Model Intercomparison Project Phase 5 (CMIP5; Taylor et al., 2012). Maps of surface air temperature change and relative precipitation change (i.e., change expressed as a percentage of mean precipitation) in different seasons are presented for the globe and for a number of different sub-continental-scale regions. Twenty-year average changes for the near term (2016–2035), for the mid term (2046–2065) and for the long term (2081–2100) are given, relative to a reference period of 1986–2005. Time series for temperature and relative precipitation changes are shown for global land and sea averages, the 26 sub-continental SREX (IPCC Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation) regions (IPCC, 2012) augmented with polar regions and the Caribbean, two Indian Ocean and three Pacific Ocean regions. In total this Annex gives projections for 35 regions, 2 variables and 2 seasons. The projections are made under the Representative Concentration Pathway (RCP) scenarios, which are introduced in Chapter 1 with more technical detail given in Section 12.3 (also note the discussion of near-term biases in Sections 11.3.5.1 and 11.3.6.1). Maps are shown only for the RCP4.5 scenario; however, the time series presented show how the area-average response varies among the RCP2.6, RCP4.5, RCP6.0 and RCP8.5 scenarios. Spatial maps for the other RCP scenarios and additional seasons are presented in the Annex I Supplementary Material. Figures AI.1 and AI.2 give a graphical explanation of aspects of both the time series plots and the spatial maps. While some of the background to the information presented is given here, discussion of the maps and time series, as well as important additional background, is provided in Chapters 9, 11, 12 and 14. Figure captions on each page of the Atlas reference the specific sub-sections in the report relevant to the regions considered on that page.

Climate Change 2013: The Physical Science Basis Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change.

Frontmatter with Foreword, Preface and Dedication

Resumo para Decisores (RPD) (p.3)

A contribuicao do Grupo de Trabalho I para o Quinto Relatorio de Avaliacao do IPCC (AR5) considera novas evidencias das alteracoes climaticas com base em muitas analises cientificas independentes a partir de observacoes do sistema climatico, registos do paleoclima, estudos teoricos de processos climaticos e simulacoes utilizando modelos climaticos. Ele baseia-se na contribuicao do Grupo de Trabalho I para o Quarto Relatorio de Avaliacao do IPCC (AR4), e incorpora novas descobertas de pesquisas posteriores. Como um componente do quinto ciclo de avaliacao, o Relatorio Especial IPCC sobre a Gestao dos Riscos de Eventos Extremos e Desastres para o Avanco da Adaptacao as Alteracoes Climaticas (SREX) e uma base importante para as informacoes sobre a mudanca meteorologica e climas extremos. Este Resumo para Decisores (RPD) segue a estrutura do relatorio do Grupo de Trabalho I. A narrativa e apoiada por uma serie de conclusoes destacadas abrangentes que, em conjunto, apresentam um resumo conciso. As seccoes principais sao introduzidas por um breve paragrafo em italico, o qual descreve a base metodologica da avaliacao.

Resumo Tecnico (RT) (p.33)

O principal objetivo deste Resumo Tecnico (RT) e fornecer a ligacao entre a avaliacao completa das multiplas linhas de evidencia independente apresentadas nos 14 capitulos do relatorio principal e o resumo altamente condensado preparado como o Resumo para Decisores (RPD) do WGI. O Resumo Tecnico serve, assim, como ponto de partida para aqueles leitores que procuram a informacao completa sobre topicos mais especificos abrangidos por esta avaliacao. Esta finalidade e facilitada pela inclusao de indicadores para os capitulos e seccoes  onde pode ser encontrada a avaliacao completa. Topicos relacionados com politicas, que abrangem muitos capitulos e envolvem muitos processos interligados no sistema climatico, sao apresentados aqui como Elementos de Foco Tematico (EFT), permitindo um rapido acesso a esta informacao.

Perguntas Frequentes (FAQ) (p.119)

Glossario (p.185)

Este glossário define alguns termos específicos tal como os Autores Principais pretendem que sejam interpretados no contexto do presente relatório.