CORDEX 15 years

2024 CORDEX is celebrating 15 years and we will therefore take the opportunity to look back on these years and also look at what is planned ahead. Information will be added during the year.

The beginning of CORDEX and the first years

We will start by looking at the beginnning.

This is the WMO bulletin from 2009 Addressing climate information needs at the regional level: the CORDEX framework.

The World Climate Research Programme (WCRP) in 2008 created the Task Force on Regional Climate Downscaling (TFRCD), chaired by Filippo Giorgi and Colin Jones. CORDEX was then initiated in 2009 at a meeting in Toulouse.

Before the start of CORDEX there were some skeptical attitudes. William Gutowski, former member of the Science Advisory Team (SAT) and later SAT co-chair, describes what it was like during a meeting:

“I was at a meeting on one WCRP working group, presenting plans for a regional climate modeling assessment program, when one member of the working group stated that regional climate modeling is mathematically ill-posed (and therefore invalid). I could not remember at the time what that meant, but I later dug around to find that a mathematically well-posed problem has a unique solution to the conditions supplied and the solution varies continuously with smooth changes in those conditions. That would then mean that climate simulation with global models is ill-posed, because for many values of the solar constant (the primary boundary condition), Earth has two stable solutions: our contemporary climate and an Ice-covered Earth. Moreover, as the solar constant varies, Earth’s climate can potentially jump discontinuously from one of those climates to the other. This anecdote is an example of the high skepticism we encountered early on, despite all the validation work that had already been occurring with RCMs.”

In response to this earlier skepticism we can today underline the fact that the CORDEX user community is large and continuously growing.

The first International Conference on the Coordinated Regional Climate Downscaling Experiment – CORDEX – was held in Trieste, Italy 21-26 March, 2011. It was devoted to a review of the status and main issues of the CORDEX initiative over the various CORDEX domains. Special sessions were devoted to the Africa domain and to the assessment of the first multi-model CORDEX simulations over this region.

Following the pioneering and successful work of the Task Force on Regional Climate Downscaling (TFRCD) which mandate ended in 2011, the WCRP established a CORDEX Science Advisory Team in 2012. In 2013 CORDEX had 13 domains and was still growing!

There was a call for an International Project Office during 2014 and at the end of the year the office opened at SMHI, in Norrkoping, Sweden. The first Director was Eleanor O’Rourke and these are her memories of CORDEX:

“I became involved in CORDEX in around 2013 helping to support some of the communication activities and events, including the ICRC- CORDEX2013 in Brussels. In 2014 discussions intensified on the need for an International Project Office for CORDEX (IPOC) given the expanding and diverse activities. Given SMHI’s strong contribution and interest in CORDEX, a bid was made to host the new IPOC and was successful. I was delighted to be selected as the founding Director and the IPOC kicked off in January 2015 with the second CORDEX-SAT meeting taking place in Norrkoping in February 2015 (photo below of everyone trying not to look too cold!).

I immensely enjoyed working with everyone in the CORDEX community as it is so diverse, enthusiastic and knowledgeable with a very clear connection to the real world impacts. I was privileged to travel to CORDEX domain meetings in Bogota, Johannesburg, and Manila – experiences, and people, I will never forget.

In terms of achievements, it is all down to the amazing CORDEX community, but seeing some of the results of funding I secured to support CORDEX Africa presented at the WCRP OSC in Kigali during my time as IPOC Director really felt great!

Happy 15th Birthday CORDEX, here’s to many more!”

CORDEX Africa and MENA domains

Africa was the region that was first prioritized within CORDEX. In a flyer from 2012 it is described why and what was initially done:

“The first priority region for CORDEX was Africa because:

  • It is highly vulnerable to climate change. Key sectors (such as agriculture, water management and health) have relatively low vulnerability thresholds to deal with climate variability and change;
  • Climate change may have significant impacts on Africa, with the potential for interaction with other stressors such as desertification and rapid population growth;
  • There is a dearth of high-resolution climate projections for the continent.

Eight groups from the CORDEX community have completed climate projections for Africa with the results now being shared and discussed among international and regional communities. A first multi-authored peer-reviewed article has been published analysing the representation of today’s climate.

Building new relationships for the future

Further, an analysis and training programme was established in early 2011 for an initial assessment of Africa relevant CORDEX model output. Teams were created according to geographical location and scientific expertise, with representation from both the physical sciences and vulnerability, impact and risk assessment communities. Such a multi-disciplinary approach facilitates the building of strong relationships between those producing climate projections and those utilising them for impact and adaptation planning providing maximum benefit.”

Link to the flyer: https://cordex.org/wp-content/uploads/2018/03/cordex_flyer2012.pdf

Since then many more peer reviewed publications have been published. A selection of publications from 2012-2020 can be found here: https://www.csag.uct.ac.za/cordex-africa/cordex-africa-publications/

The programme mentioned above was part of the workshop series CORDEX Africa Analysis Phase 1 2011-2012 which resulted in 13 journal publications and build the foundations of the CORDEX-Africa community that includes climate, hydrology, agriculture and hydrology scientists. Phase 2 took place in 2015-2017 and both are very good examples of capacity building activities within the domain. A highlight of the effort was how CORDEX-Africa participants decided to produce a series of papers targeting the IPCC Special Report on 1.5 degrees (SR15) and this resulted in Box 3.1 in Chapter 3 of the report on the impact of 1.5 degrees of warming on Africa. Furthermore, in the 6th assessment cycle of the IPCC (AR6) CORDEX-Africa had 7 lead authors in various chapters of Working Groups 1 and 2, and the special reports on 1.5 degrees and climate change and land. The full report from Phase 2 can be read here: https://www.csag.uct.ac.za/wp-content/uploads/2015/06/CORDEX-Africa_workshops_2nd_phase.pdf.

The work within the domain has continued and workshops have been held both online and in-person. More recently a workshop was held online in December 2021 that gathered thirty participants from thirteen countries. https://cordex.org/2022/03/28/cordex-workshop-for-thirteen-african-countries/ and was then followed up by a joint in-person workshop organized by CORDEX Africa and the CORDEX Flagship South-East Africa Pilot Study held in Johannesburg in April 2022 after being postponed due to Covid-19. The purpose of these workshops was extended collaboration and to discuss the most pressing issues and gaps in climate information in order to enable well informed decisions for Africa.

There are also currently two Flagship Pilot Studies focusing on Africa:

ELVIC – Climate Extremes in the Lake Viktoria Basin
https://cordex.org/experiment-guidelines/flagship-pilot-studies/endorsed-cordex-flagship-pilote-studies/africa-elvic-climate-extremes-in-the-lake-viktoria-basin/

Modelling the southeast African regional climate
https://cordex.org/experiment-guidelines/flagship-pilot-studies/endorsed-cordex-flagship-pilote-studies/africa-modelling-the-southeast-african-regional-climate/

The MENA (Middle East and North Africa) CORDEX domain was established in 2012, user-driven by a need of high-resolution regional climate information from the Regional Initiative for the Assessment of the Impact of Climate Change on Water Resources and Socio-Economic Vulnerability in the Arab Region (RICCAR, https://riccar.org/).

Since 2012 regional downscaling activities in the MENA region have been growing together with the number of participants involved. The first results from the MENA domain were presented at the International Conference on Regional Climate - CORDEX 2013 in Brussels where a scoping meeting for the MENA domain was held. An active working group of several regional climate modelling teams from the region and Europe was successfully launched in November 2014 at the CORDEX MENA meeting in Nicosia (Cyprus). The first MENA CORDEX simulations were made publicly available on the Earth System Grid Federation (ESGF) in 2013.

The first common publication effort from the MENA CORDEX:
Zittis G., Hadjinicolaou P., Almazroui M., Bucchignani E., Driouech F., El Rhaz K., Kurnaz L., Nikulin G., Ntoumos A., Ozturk T., Proestos Y., Zaaboul R., Lelieveld J. (2020) Business-as-usual will lead to ultra-extreme heatwaves in the Middle East and North Africa. npj Climate and Atmospheric Science https://www.nature.com/articles/s41612-021-00178-7

Although the number of active participants is rather small in the domain at the moment there are a few modelling groups that are considering in proceeding with CMIP6 downscaling and a few presentations were also made during a workshop in Saudi Arabia in 2023. Information about the workshop can be found in the domain report for 2023: https://cordex.org/domains/domain-activities-2/domain-activities-2023/

Since the CORDEX Africa and MENA CORDEX domain share the North African region collaboration is important and it will be developed further as the CORDEX Africa domain is about to form a North African team.

The current Points of Contact in these domains are:

Africa: Chris Lennard, Nana Ama Browne Klutse, Amira Nasser Mostafa and Rondrotiana Barimalala

MENA: Panos Hadjinicolaou, Fatima Driouech and Mansour Almazroui.

Africa domain

MENA domain

Group photo from one of the CORDEX Africa Workshops

Med-CORDEX

Med-CORDEX is an open club of Mediterranean climate model developers and users, driven by scientific curiosity. It is self-organized, and based on voluntary efforts and is endorsed by CORDEX, Med-CLIVAR, and HyMeX.
Its scientific focus is on the regionally closed energy and water cycles, which implies developing and applying coupled ocean-atmosphere-land high-resolution climate models.

Over the past 15 years, our overarching scientific goals have been to:

  • understand the past variability of the Mediterranean regional climate system and characterize its potential future evolution;
  • investigate, understand, and improve the description of regional climate phenomena and
  • contribute to the characterization of the impacts of Mediterranean climate change

Med-CORDEX began in 2009 as an official CORDEX domain, following the European CIRCE project and funded by the HyMeX program. It develops reference modeling frameworks to provide coordinated regional climate simulations, focusing on the various components of the Mediterranean climate system, including the atmosphere, land, ocean, and aerosols.
Multi-channel coordination is achieved through a mailing list (medcordex@meteo.fr), a website (www.medcordex.eu), a Slack-based discussion forum (medcordex.slack.com), a Zenodo community (https://zenodo.org/communities/medcordex/), and an active steering committee (medcordex-sc@meteo.fr).
Med-CORDEX has published numerous scientific works, including two reference publications (Ruti et al. 2016, Somot et al. 2018b) and 145 scientific articles between 2011 and 2024, including a special issue in Climate Dynamics in 2018 and various multi-model studies.
The Med-CORDEX centralized database hosted by ENEA includes 125 datasets (12 TB uploaded, 42 TB downloaded), contributed by 15 institutes and used by 305 registered users. This database supports extensive research and collaboration within the Mediterranean climate community. Three of the first endorsed CORDEX Flagship Pilot Studies (FPSs) were proposed by Med-CORDEX, focusing on key regional climate processes and their interactions:

Role of the natural and anthropogenic aerosols in the Mediterranean region: past climate variability and future climate sensibility

Role of the air-sea coupling and small-scale ocean processes on regional climate

Convective phenomena at high resolution over Europe and the Mediterranean

Over the years, Med-CORDEX's contributions to Mediterranean climate and ocean science have been recognized by international initiatives such as Med-CLIVAR, C3S, IPCC-AR6, and MedECC-MAR1. Notably, it was the only coordinated initiative providing ocean variables from regional climate models to the IPCC-AR6 interactive atlas.

In 2023 Med-CORDEX published an updated version of the Med-CORDEX-CMIP6 baseline run protocol: Med-CORDEX phase 3: Common protocol for the Baseline runs for the CORDEX-CMIP6 framework.

The current Points of Contact:

MED-CORDEX: Erika Coppola, Bodo Ahrens, Gabriel Jordà, Gianmaria Sannino, Samuel Somot and Fabien Solmon

MED-CORDEX domain

Group photo from the 6th Med-CORDEX workshop in Toulouse in 2019. The same place where it all started.