The Intergovernmental Panel on Climate Change (IPCC) at its 61^st Plenary Session in Sofia, Bulgaria, has agreed on the outlines of the IPCC Special Report on Climate Change and Cities and the 2027 IPCC Methodology Report on Inventories for Short-lived Climate Forcers. More than 230 delegates from 114 member governments attending the week-long meeting in the Bulgarian capital also agreed on the respective timelines of the two reports.

“The Panel’s decision today paves the way for the critically important next stages in our work — the nomination and selection of authors who will actually write these two reports. We are keen for these processes to bring on board the most diverse and inclusive group of authors yet,” said IPCC Chair Jim Skea.

“The timing of these two reports confirms the continued policy relevance of IPCC scientific reports.”

The calls for nominations of authors are scheduled for release as early as next week.

The agreed outline of the Special Report on Climate Change and Cities includes trends, challenges and opportunities for cities in a changing climate, the actions and solutions to reduce urban risks and emissions, how to facilitate and accelerate change in the context of cities, and solutions by city and types and regions. Panel’s approval and publication of this Special Report are scheduled for March 2027. The detailed outline is available here.

The scientific leadership of the Special Report on Climate Change and Cities is shared between the IPCC’s three Working Groups. The Co-Chairs of Working Group II – Winston Chow and Bart van den Hurk – who are leading the report’s production, stressed that this Special Report is of immense relevance to many stakeholders around the world for implementing effective climate action in cities, adding that their team is dedicated to its timely development over the next three years.

The 2027 IPCC Methodology Report on Inventories for Short-lived Climate Forcers will guide the preparation and reporting of a national inventory of emissions of short-lived climate forcers. The planned publication time of this Methodology Report is July 2027. The detailed outline is available here.

Based on the report from the upcoming scoping meeting of the three Working Groups’ contributions to the Seventh Assessment Report, which is scheduled to take place in December 2024, at its next Plenary in early 2025, the Panel will agree on their respective scope, outlines, and work plans, including schedules and budgets.

To request interviews with the IPCC Chair and other Bureau Members, please email ipcc-media@wmo.int.

For more information please contact:

IPCC Press Office, Email: ipcc-media@wmo.int

Notes for editors

What is the IPCC?

The Intergovernmental Panel on Climate Change (IPCC) is the UN body for assessing the science related to climate change. It was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988 to provide political leaders with periodic scientific assessments concerning climate change, its implications and risks, as well as to put forward adaptation and mitigation strategies. In the same year the UN General Assembly endorsed the action by the WMO and UNEP in jointly establishing the IPCC. It has 195 member states.

Thousands of people from all over the world contribute to the work of the IPCC. For the assessment reports, experts volunteer their time as IPCC authors to assess the thousands of scientific papers published each year to provide a comprehensive summary of what is known about the drivers of climate change, its impacts and future risks, and how adaptation and mitigation can reduce those risks.

The IPCC has three working groups: Working Group I, dealing with the physical science basis of climate change; Working Group II, dealing with impacts, adaptation and vulnerability; and Working Group III, dealing with the mitigation of climate change. It also has a Task Force on National Greenhouse Gas Inventories that develops methodologies for measuring emissions and removals.

IPCC assessments provide governments, at all levels, with scientific information that they can use to develop climate policies. IPCC assessments are a key input into the international negotiations to tackle climate change. IPCC reports are drafted and reviewed in several stages, thus guaranteeing objectivity and transparency.

About the Seventh Assessment Cycle

Comprehensive scientific assessment reports are published every 5 to 7 years. The IPCC is currently in its seventh assessment cycle, which formally began in July 2023 with the elections of the new IPCC and Taskforce Bureaus at the IPCC’s Plenary Session in Nairobi. 

At its first Plenary Session in the seventh assessment cycle – the 60^th Plenary Session in Istanbul, Türkiye, in January 2024 – the Panel agreed to produce in this cycle the three Working Group contributions to the Seventh Assessment Report (AR7), namely the Working Group I report on the Physical Science Basis, the Working Group II report on Impacts, Adaptation and Vulnerability and the Working Group III report on Mitigation of Climate Change. The Synthesis Report of the Seventh Assessment Report will be produced after the completion of the Working Group reports and released by late 2029.

The Panel decided already during the previous cycle to produce a Special Report on Climate Change and Cities and a Methodology Report on Short-lived Climate Forcers during AR7. Scientists have also been asked to deliver a Methodology Report on Carbon Dioxide Removal Technologies, Carbon Capture Utilization and Storage.

In addition, a revision of the 1994 IPCC Technical Guidelines on impacts and adaptation as well as adaptation indicators, metrics and guidelines, will be developed in conjunction with the Working Group II report and published as a separate product.

IPCC’s latest report, the Sixth Assessment Report, was completed in March 2023 with the release of its Synthesis Report, which provides direct scientific input to the first global stocktake process under the United Nations Framework Convention on Climate Change at COP28 in Dubai.

The Sixth Assessment Report comprises three Working Group contributions and a Synthesis Report. The Working Group I contribution Climate Change 2021: the Physical Science Basis was released on 9 August 2021. The Working Group II contribution, Climate Change 2022: Impacts, Adaptation and Vulnerability, was released on 28 February 2022. The Working Group III contribution, Climate Change 2022: Mitigation of Climate Change, was released on 4 April 2022 and the Synthesis Report on 20 March 2023. The Synthesis Report to the Sixth Assessment Report, distils and integrates the findings of the three Working Group assessments as well as the three Special Reports released in 2018 and 2019.

The special reports were on Global Warming of 1.5°C (October 2018.), Climate Change and Land (August 2019) and, the ocean and cryosphere in a changing climate (September 2019).

For more information visit www.ipcc.ch.

The website includes outreach materials including videos about the IPCC and video recordings from outreach events conducted as webinars or live-streamed events.

Most videos published by the IPCC can be found on our YouTube channel.