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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

Dans cette contribution au cinquième Rapport d’évaluation du GIEC (RE5), le Groupe de travail I (GTI) examine de nouveaux éléments concernant le changement climatique sur la base de nombreuses analyses scientifiques indépendantes d’observations du système climatique, d’archives paléoclimatiques, d’études théoriques des processus climatiques et de simulations à l’aide de modèles climatiques. Il s’appuie sur sa contribution au quatrième Rapport d’évaluation du GIEC (RE4) et incorpore de nouveaux résultats de recherche obtenus depuis. Composante du cinquième cycle d’évaluation, le rapport spécial intitulé Gestion des risques de catastrophes et de phénomènes extrêmes pour les besoins de l’adaptation au changement climatique (SREX) représente un socle d’informations important sur l’évolution des extrêmes météorologiques et climatiques. Le présent Résumé à l’intention des décideurs suit la structure du rapport du Groupe de travail I. Ce texte s’accompagne d’une mise en exergue des principales conclusions qui, rassemblées, fournissent un résumé concis. L’introduction des principales sections se présente sous la forme d’un bref paragraphe en italique, qui souligne les bases méthodologiques de l’évaluation.

Climate Change 2013: The Physical Science Basis is the contribution of Working Group I (WGI) to the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC). This comprehensive assessment of the physical aspects of climate change puts a focus on those elements that are relevant to understand past, document current and project future climate change. The assessment builds on the IPCC Fourth Assessment Report (AR4)1 and the recent Special Report on Managing the Risk of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX)2 and is presented in 14 chapters and 3 annexes. The chapters cover direct and proxy observations of changes in all components of the climate system; assess the current knowledge of various processes within, and interactions among, climate system components, which determine the sensitivity and response of the system to changes in forcing; and quantify the link between the changes in atmospheric constituents, and hence radiative forcing (RF)3, and the consequent detection and attribution of climate change. Projections of changes in all climate system components are based on model simulations forced by a new set of scenarios. The Report also provides a comprehensive assessment of past and future sea level change in a dedicated chapter. Regional climate change information is presented in the form of an Atlas of Global and Regional Climate Projections (Annex I). This is complemented by Annex II: Climate System Scenario Tables and Annex III: Glossary.

The Working Group I contribution to the IPCC’s Fifth Assessment Report (AR5) considers new evidence of climate change based on many independent scientific analyses from observations of the climate system, paleoclimate archives, theoretical studies of climate processes and simulations using climate models. It builds upon the Working Group I contribution to the IPCC’s Fourth Assessment Report (AR4), and incorporates subsequent new findings of research. As a component of the fifth assessment cycle, the IPCC Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX) is an important basis for information on changing weather and climate extremes.

This Summary for Policymakers (SPM) follows the structure of the Working Group I report. The narrative is supported by a series of overarching highlighted conclusions which, taken together, provide a concise summary. Main sections are introduced with a brief paragraph in italics which outlines the methodological basis of the assessment.

Explore terms that are used in the report to better understand key concepts and the meaning behind how terms are used.