Missions

The Postdoctoral researcher will join the CECI laboratory and the TRACCS community to work on a project on investigating the mechanisms of future changes in high-impact phenomena and the added value of kilometer-scale climate modeling.

Km-scale Regional Climate Models (RCMs), or Convective Permitting RCMs, are now providing long-term climate projections, but their full potential for characterizing regional climate change still remains largely unexplored. These models offer significant advantages, including improved representation of convective events and improved simulation of extreme precipitation. They also provide with a more realistic depiction of areas with complex topography. Many of these areas were not correctly modeled using lower-resolution climate models. For example, at the km-scale, we expect better representation of coastal wind patterns and diurnal variations, and improved simulation of high-wind corridors. We also expect improved simulation of altitude-dependent temperature variations in mountainous regions. Some studies also suggest these models could alter the sign of soil-moisture precipitation feedback, which has potentially major implications for future hydroclimate changes, including droughts and heatwaves. However, the precise added value of km-scale regional climate modeling for future climate projections is still not well evaluated, as their broader availability is recent. To ensure the robustness of the changes, km-scale projections must be assessed in comparison with lower-resolution projections.

The physical complexity of Earth System Models (ESMs) is not yet matched by km-scale RCMs or even RCMs. A necessary trade-off exists between a model's resolution and its complexity, given computational costs and limitations. For instance, km-scale RCMs generally lack ocean coupling, use basic land surface models, or omit interactive aerosols. Such simplifications could ultimately negate the added value of higher resolution if crucial mechanisms are overlooked. Furthermore, to truly realize their potential, km-scale RCMs may require schemes even more detailed than those in lower-resolution models. For example, while their detailed orography promises valuable insights in mountainous regions, highly detailed snow schemes might be essential to obtain the most realistic projections there. Similarly, the impact of air-sea interactions in coastal regions on winds and diurnal variations may not be accurately reflected in uncoupled km-scale simulations.


The main goal of this Postdoctoral will be to explore the mechanisms responsible for changes in local phenomena of interest and to evaluate the added value of km-scale RCMs for projecting future climate change in that context. The study will specifically focus on climate extremes and high-impact events where km-scale modelling is expected to be particularly valuable. This includes droughts and heatwaves (with an emphasis on land-atmosphere interactions), local wind extremes (in coastal areas and wind corridors), and temperature changes within mountainous regions and coastal areas.

Activités

The following research will be conducted by the recruited researcher:
• Detailed analysis of mechanisms behind future changes: This involves pinpointing the mechanisms driving changes in the events of interest and understanding how they are impacted by resolution
• Comparison with standard RCMs: Changes and their underlying mechanisms will be compared with projections from standard Regional Climate Models.
• Robustness assessment: The robustness of findings will be assessed by including km-scale climate projections from other European groups.
• CNRM-AROME case studies: Further investigation of identified mechanisms could be conducted using the CNRM-AROME km-scale model for events of particular interest. This may include testing the role of the resolution, internal variability within the model, and specific condition such as the surface conditions.
While the candidate will initially focus on Western Europe due to the availability of km-scale simulations and the international context, there is also broader interest in other regions, such as Western Africa and tropical islands.
Ultimately, the project's focus is flexible and can be tailored to the candidate's research interests.

Compétences

Requested qualifications:
• Ph.D. in climate science, or another relevant field (experience in regional climate modeling is appreciated).
• Demonstrated process-based understanding of the climate system.
• Research and publication track record in a relevant field, commensurate with opportunity. Ability in conducting research, both independently and as an active member of a research team.
• Experience in handling large spatio-temporal geophysical datasets.
• Good programming skills in Python and Linux shell scripting.
• Good English language skills.
• Good oral and written communication skills.
Responsibilities:
• Ensure research is carried out in line with the project's aims and under the limited direction of the supervisors.
• Writing scientific papers, coordinating research activities, participating in the setting of research directions and any other research activities as required
• Maintain a strong focus on communication by interacting with the national and international community, publishing in highly ranked journals, and presenting to peers at local and international conferences.
• Assist in the supervision of master students in this project area as opportunities arise

Contexte de travail

The recruitment is part of the TRACCS (Transforming Climate Modelling for Climate Services, https://pepr-traccs.fr) research programme. TRACCS is a major 8-year initiative that seeks to accelerate climate model development to meet societal needs in mitigating and adapting to climate change impacts. Its activities range from improving climate model reliability and developing downscaling and bias correction methods to creating prototype climate services co-constructed with relevant stakeholders. TRACCS also explores technological and scientific advancements, such as new computing architectures and artificial intelligence techniques, which open new avenues for climate science. This initiative contributes to training the next generation of climate experts across all aspects of climate modeling and the development, provision, and use of climate services. The programme is organised into 10 targeted projects and a governance project. The present position is part of the TRACCS-PC10-LOCALISING project. LOCALISING  aims to define and explore the best way to provide accurate and reliable local climate information to support adaptation strategies. LOCALISING develops multi-component, fully coupled local climate system models to achieve kilometer and hourly scale representation. This is achieved by combining dynamic models with statistical approaches to characterize local-scale uncertainty.

Working conditions:
• Contract duration: 36 months, starting as early as November 2025, subject to availability. Possibility of 6-month extension.
• Location: CECI (CNRS/Cerfacs/IRD), Toulouse.
• Employer: CNRS.
• A competitive salary will be offered, commensurate with experience and qualifications.
• A genuinely inclusive and equitable work environment.
• Flexible working arrangements with possibility to work from home up to two days per week.

Closing date of the call is September 10th, 2025.

Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.

Contraintes et risques

none