CORDEX – a global collaboration for regional climate information

Global climate models describe how the Earth's climate may change in the future. However, decisions on urban planning, risk management, and climate adaptation, for example, are made at the local and regional levels, where more detailed information is required. Regional processing of global information is therefore necessary.

CORDEX was created after the IPCC's fourth climate report (2007), which clearly showed that there was a lack of detailed regional information on climate change. Initially, the focus was on Africa, but today CORDEX covers almost all of the world's land areas as well as the Arctic.

The goal is to deliver robust, standardized, and easily accessible climate information that can be used in vulnerability, impact, and adaptation studies at the regional and local levels.

Benefits for Sweden and the world

CORDEX has contributed to both national and international benefits.

• National benefits: The results from CORDEX are used in Sweden for climate adaptation and planning, and form a central part of SMHI's climate scenario service. The work supports the government's climate goals and contributes to well-founded decisions on risk strategies and measures.
• International benefits: CORDEX has built networks around the world and played a particularly important role in capacity building in developing countries. SMHI has contributed the most regional simulations globally, including for Africa, where there is a great need for detailed climate information.

One example of the results is a so-called writeshop in Africa that led to many scientific articles, six of which contributed to the IPCC's climate report. In this way, CORDEX has strengthened the link between research, practical application, and international decision-making.

CORDEX International Project Office at SMHI (2015–2025)

In order to coordinate the rapidly growing activities, an International Project Office for CORDEX (IPOC) was established in 2015. The World Climate Research Programme (WCRP) appointed SMHI as host for the office, which was based in Norrköping until 2025.

The office has played a central role in CORDEX, including:

• supporting the scientific advisory team (CORDEX-SAT)
• organizing international conferences on regional climate (ICRC 2016 in Stockholm, 2019 in Beijing, 2023 in Trieste and Pune)
• initiated and supported workshops, workshop series, and training courses in several regions
• secured links to research on climate impact, effects, and adaptation (VIA)
• driven work on funding and international collaboration
• Coordinated CORDEX activities and development

Those who have worked at IPOC during SMHI's hosting period are Iréne Lake (director), Lindha Nilsson, Sophia Kark, Miranda Gatti Ståhl, Anna Eronn, EvaMarie Törnström, Helena Martins, and Eleanor O'Rourke (director during the first year).

Examples of projects and activities

Over the years, CORDEX and IPOC have been involved in a number of important initiatives:

• CORDEX Africa – development of scenarios for a region where information was previously lacking on a regional scale, with a particular focus on knowledge gaps and adaptation.
• Workshop series in Africa, Asia, and Latin America – contributed, among other things, to local research networks and publications used in the IPCC's work.
• International CORDEX conferences – brought together researchers, decision-makers, and users for knowledge exchange and joint planning.
• Copernicus projects and other international collaborations – strengthened access to open data and useful climate information globally.

The future of CORDEX

SMHI continues to organize new workshops with partners we have connected with through CORDEX, including in Africa, where the focus is on strengthening capacity and developing decision-making tools for regions that are particularly vulnerable to climate change. Going forward, SMHI will continue to be part of the global CORDEX community, which we have seen benefits our research, our projects, our opportunities for collaboration, and our society.

The work within CORDEX also continues to evolve—with new methods such as machine learning and AI, with an increased focus on extreme events, and with new collaborations in different parts of the world. SMHI is also involved in the new scenarios being developed in CMIP6 and planned for CMIP7 and beyond, which will provide updated and higher-resolution regional downscalings.

In the video from 2024, you can learn more about what CORDEX is and what the community does around the world.