18 May 2015 - 20 May 2015
Laxenburg, Austria

IIASA Hosting IPCC Expert Meeting on Scenarios

Energy Program Director, Keywan Riahi, serves as the meeting's organizer and host as well as a member of the meeting's Scientific Steering Committee.

© Skypixel | Dreamstime

© Skypixel | Dreamstime

The meeting’s Scientific Steering Committee consists of: Ottmar Edenhofer (Potsdam Institute for Climate Impact Research/PIK), Keywan Riahi (IIASA), Vicente Barros (University of Buenos Aires), Mercedes Bustamante (University of Brasilia) Timothy Carter (Finnish Environment Institute), Renate Christ (IPCC), Ismail El Gizouli (Higher Council for Environment and Natural Resources, Sudan), Chris Field (Carnegie Institution for Science), Elmar Kriegler (Potsdam Institute for Climate Impact Research/PIK), Jean-Francois Lamarque (University Corporation for Atmospheric Research), Katherine Mach (IPCC WG II TSU), Michael Mastrandrea (IPCC WG II TSU), Ritu Mathur (The Energy and Resources Institute), Ramon Pichs-Madruga (Centro de Investigaciones de la Economia Mundial, Cuba), Jan Heeman-Minx (IPCC WGIII TSU), Brian O’Neill (National Center for Atmospheric Research), Gian-Kasper Plattner (University of Bern), Dahe Qin (China Meteorological Administration), Youba Sokona (The South Center), Thomas Stocker (University of Bern) and Tianjun Zhou (Institute of Atmospheric Physics, Chinese Academy of Sciences).

IPCC and the Scenarios Research Community

Long-term scenarios of future societal development, climate change, and other environmental change are essential ingredients of IPCC reports. They are the basis for evaluating potential climate change impacts as well as socio-economic mitigation and adaptation pathways.

In 2006, the Panel decided to implement a new institutional setup for the development of long-term scenarios: rather than coordinating and approving new scenarios itself, the process of new scenario development should be coordinated by the research community. The IPCC has catalyzed the development and assessed the results from the new scenarios in Fifth Assessment Report (AR5). After completion of the AR5 and reflecting the division of labor in the development of long-term scenarios, the IPCC intends at this meeting to continue the dialogue with the research communities in a timely manner.

IPCC Expert Meeting on Scenarios

The meeting shall facilitate the dialogue between the IPCC and research communities; take stock on the achievements of the process during the Fifth Assessment Report (AR5) cycle; share available information across scientific communities; and discuss the role of scenarios in future IPCC products. With the organization of the meeting, the IPCC intends to bring together scientific groups with diverse expertise and backgrounds to share their experiences and expectations related to the scenario community activities.

IIASA is co-hosting this meeting with the IPCC Working Group III, another collaboration within the long-term partnership between IIASA's Energy Program and the IPCC TSU Working Group III researchers.

Just before the IPCC meeting a new set of Scenarios for the so-called Shared Socioeconomic Pathways (SSPs) has been released. The new SSP scenarios have been developed between 2012 and 2015, and are available now for review by the scientific community. The preliminary SSP scenarios are part of a new framework that the climate change research community has adopted to facilitate the integrated analysis of future climate impacts, vulnerabilities, adaptation, and mitigation. (click here in order to participate in the review).

Against this background, the three main objectives of the expert meeting are:

1) Assess the use of scenarios of climate change and/or societal development in the three AR5 Working Group reports and the Synthesis report, with the goal to identify needs for improving the use of common scenarios in climate change research to allow a more integrated assessment of mitigation, adaptation, and climate change impacts across the entirety of IPCC work in the future.

2) Evaluate progress and research achievements from the scenario framework activities around the Representative Concentration Pathways (RCPs) and the Shared Socioeconomic Pathways (SSPs). The focus will be on the current status of the development of new socio-economic scenarios, including the development of narratives, quantifications of SSPs, related IAM scenarios as well as early applications to mitigation, adaptation, and climate change impacts analysis. The meeting provides the opportunity for sharing information on recently completed scenario products that are ready for use by the research community and for identifying gaps and needs for producing the relevant literature in order to allow a more integrated assessment of scenarios in future work of the IPCC.

3) Based on above stock-taking, the experts will discuss the possible role of scenarios in future IPCC products, and particularly, how the IPCC can facilitate the community scenario process to make progress towards new and fully integrated scenarios. 

Energy Program's Work on Shared Socioeconomic Pathways (SSPs) 

The Energy Program is co-coordinating the overall SSP scenario development process, which involves other major integrated assessment teams from Asia, Europe, and the USA. The development of the SSPs continues to guide important methodological improvements and extensions of the present IIASA-ENE modeling tools, including the endogenous representation of land-use change with the ESM Program.

All data of the SSPs have been made publicly accessible for an extensive community review until June 25th, 2015. Similar to earlier SSP datasets for the community, the scenario data is hosted by the IIASA-SSP interactive database. Furthermore, IIASA's Energy Program is host of the IPCC AR5 Scenarios database of the Working Group III of the IPCC.  

The SSPs describe plausible alternative trends in the evolution of society and natural systems over the 21st century at the level of the world, regional and sometimes national development. They consist of narrative storylines and a set of quantified measures of development.

With the conceptual framework of the SSPs successfully completed in 2013, activities in 2014 and 2015 focused on the finalization of qualitative narratives and the further development of quantitative scenarios for the SSPs. Collaboration at IIASA between the ENE Program and the Ecosystems Services and Management (ESM) and Mitigation of Air Pollution and Greenhouse Gases (MAG) programs has focused on the so-called middle of the road scenario SSP2.

Introduction to the SSP Databases

The SSP database aims at the documentation of quantitative projections of the so-called Shared Socioeconomic Pathways (SSPs) and related Integrated Assessment scenarios. The SSPs are part of a new framework that the climate change research community has adopted to facilitate the integrated analysis of future climate impacts, vulnerabilities, adaptation, and mitigation.

Information about the scenario process and the SSP framework can be found in Moss et al. (2010), van Vuuren et al. (2014) and O‘Neil et al. (2014) and Kriegler et al. (2014). The framework is built around a matrix that combines climate forcing on one axis (as represented by the Representative Concentration Pathways: van Vuuren et al, 2011) and socio-economic conditions on the other. Together, these two axes describe situations in which mitigation, adaptation and residual climate damage can be evaluated. The SSP quantifications build upon the collaborative effort between the IAV and IAM community, which has met in a series of meetings and identified a limited set of five SSP storylines/narratives (O‘Neill et al, 2015). The narratives describe the main characteristics of the SSP future development pathways. They served as the starting point for the identification of internally consistent assumptions for the quantification of SSP elements. Different modeling tools can be used to develop quantifications of these storylines, including factors like population, economic development, land use and energy use.

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Last edited: 18 May 2015


Keywan Riahi

Program Director

Energy, Climate, and Environment Program

Integrated Assessment and Climate Change Research Group

Pollution Management Research Group

Sustainable Service Systems Research Group

T +43(0) 2236 807 491

Scenarios and IPCC databases hosted at IIASA

International Institute for Applied Systems Analysis (IIASA)
Schlossplatz 1, A-2361 Laxenburg, Austria
Phone: (+43 2236) 807 0 Fax:(+43 2236) 71 313