Fifth Assessment Report

Fifth Assessment Report
Name	Fifth Assessment Report
Author	Intergovernmental Panel on Climate Change
Country	International
Language	English
Subject	Climate change assessment
Publisher	Intergovernmental Panel on Climate Change
Pub date	2013–2014
Preceded by	Fourth Assessment Report
Followed by	Sixth Assessment Report

Fifth Assessment Report

The Fifth Assessment Report provided a comprehensive assessment of scientific, technical, and socio-economic information relevant to understanding climate change and its impacts, involving hundreds of authors from institutions such as National Aeronautics and Space Administration, National Oceanic and Atmospheric Administration, European Commission, Met Office, and World Meteorological Organization. It synthesized evidence from observational programs like Argo (oceanography), satellite missions including Landsat program, and modeling initiatives such as the Coupled Model Intercomparison Project to inform policy arenas exemplified by the United Nations Framework Convention on Climate Change and negotiations at United Nations Climate Change Conference sessions.

Overview

The report was produced by the Intergovernmental Panel on Climate Change and released in stages between 2013 and 2014, combining contributions from working groups and a cross-cutting Synthesis Report, drawing on datasets from IPCC Fourth Assessment Report successors and research centers including Hadley Centre, Princeton University, NASA Goddard Institute for Space Studies, Scripps Institution of Oceanography, and Max Planck Institute for Meteorology. It addressed attribution studies connected to events like the European heat wave of 2003 and long-term trends observed in records such as Mauna Loa Observatory carbon dioxide measurements and Paleocene–Eocene Thermal Maximum comparisons.

Preparation and Process

The preparation followed procedures endorsed by the IPCC plenary, with authors appointed from nominations by governments and observer organizations including World Health Organization and International Energy Agency. Lead authors coordinated contributions from coordinating lead authors and review editors affiliated with universities such as University of Oxford, Massachusetts Institute of Technology, Australian National University, and institutions like National Center for Atmospheric Research. The process incorporated multiple draft reviews by expert reviewers from agencies like United States Environmental Protection Agency and stakeholder review rounds involving delegations to Intergovernmental negotiations at sessions of the United Nations Framework Convention on Climate Change.

Key Findings

Key findings linked observed warming to anthropogenic influences, citing evidence from paleoclimate archives such as Greenland ice sheet cores and Vostok (Antarctica) records, and projecting future changes under Representative Concentration Pathways used in climate modeling. The report quantified sea level rise with references to processes affecting Antarctic ice sheet and Greenland ice sheet dynamics and assessed risks to systems including Coral reefs and Arctic sea ice, while evaluating mitigation potential in sectors represented by International Maritime Organization and International Civil Aviation Organization pathways.

Working Group Reports

Working Group I covered the physical science basis with contributions from modeling centers such as Met Office Hadley Centre, GFDL, and NOAA Geophysical Fluid Dynamics Laboratory; Working Group II addressed impacts, adaptation and vulnerability drawing on case studies from Small Island Developing States, Amazon rainforest, and Sahara Desert-adjacent nations; Working Group III evaluated mitigation pathways and technologies including deployment scenarios involving Intergovernmental Panel on Climate Change Special Report on Renewable Energy Sources and Climate Change Mitigation-related research, energy transitions analyzed with input from International Renewable Energy Agency and International Energy Agency. Each report included chapters authored by experts affiliated with institutions like University of Cambridge, Columbia University, Potsdam Institute for Climate Impact Research, and Tyndall Centre for Climate Change Research.

Synthesis and Summary for Policymakers

The Synthesis Report and the Summary for Policymakers distilled cross-cutting conclusions for decision-makers participating in forums such as the G20 and United Nations General Assembly, emphasizing linkages between mitigation commitments under the Kyoto Protocol and prospective nationally determined contributions discussed ahead of the Paris Agreement. The Summary for Policymakers underwent line-by-line approval by representatives from member states, with input from scientific delegations including China Meteorological Administration, United States Geological Survey, Indian Institute of Science, and Environment and Climate Change Canada.

Reception and Impact

The report influenced international diplomacy at United Nations Climate Change Conference, 2013 and subsequent negotiations culminating in the Paris Agreement; it informed national policy instruments in jurisdictions such as the European Union, United States, China, and Australia. It shaped research priorities at funding bodies like the National Science Foundation and programs at institutions including Woods Hole Oceanographic Institution and CSIRO, and was cited in assessments by organizations such as the World Bank and International Monetary Fund.

Criticism and Controversies

Criticism focused on perceived conservatism in risk estimates and on debates over uncertainty framing, with commentary from actors including Heartland Institute and proponents associated with Climatic Research Unit discussions. Controversies also arose around the Summary for Policymakers approval process involving negotiations among delegations from Brazil, India, Saudi Arabia, and United States, and scrutiny by media outlets such as The New York Times and The Guardian. Scientific debate continued in journals like Nature (journal), Science (journal), and Geophysical Research Letters regarding projections for ice-sheet collapse and regional climate extremes.

Category:Intergovernmental Panel on Climate Change reports