PhD thesis about permafrost modelling (M/F)

Job Description

Thesis Subject

This PhD thesis aims at studying the impacts of climate change-induced permafrost thaw in the Arctics, by using advanced thermo-hydro-mechanical modelling capabilities developed in the framework of the PERMACHANGE project. Permafrost is soil permanently frozen in depth, covering a quarter of Northern Hemisphere lands. Due to climate warming, it is experiencing fast and widespread thawing, and this induces essential impacts in the Arctics, both on the environment (e.g., water resources) and on societies (e.g., infrastructure destabilisation). These permafrost thaw impacts are expected to generate significant additional financial costs for maintaining key human activities, up to hundreds of billions of dollars by the end of the century. Moreover, permafrost thaw will likely trigger critical climatic feedback. Thus, anticipating permafrost thaw by numerical simulations is paramount for ensuring the resilience of Arctic environments, societies and activities while controlling the associated costs. Meanwhile, numerical simulations of permafrost dynamics are highly complex and challenging due to the strong non-linearities and couplings involved in the related physics.
The PERMACHANGE project builds on high performance computing (Orgogozo et al., 2023, Xavier et al., 2024) and hydrid modelling (Chinesta et al., 2020; Champaney et al., 2022) for developing a site scale (~10's of km2) permafrost thermo-hydological hybrid twin, to be coupled with state of the art freezing/thawing soil mechanics machine learning-based surrogate models (Richa et al., 2024, Tristani et al., 2024) using symbolic regression approaches (e.g. Guayacán-Carrillo and Sulem, 2024). By doing so, PERMACHANGE will enable unprecedented high fidelity and high efficiency numerical simulations of subterranean heat and water transfers and terrain stability under permafrost thaw.
This PhD thesis aims at applying this advanced modelling chain to three sites of long-term permafrost monitoring in the European Arctics: Abisko in Northern Sweden, Ny-Ålesund in Svalbard and Ilulissat in Greenland. In this way, projections of permafrost-thaw impacts at different time scale will be done, from the seasonal time scale to the century time scale. This will allow us to demonstrate the capabilities of the PERMACHANGE advanced modelling workflow and to provide critical information to local stakeholders as an alert for decision-making regarding emergency actions for short-term permafrost thaw hazards and information for long-term land planning, taking into account climate change. It will also enable establishing a general procedure for the operational application of this advanced permafrost modelling workflow all across the Arctics and contribute to the gathering of the relevant information needed for improving permafrost modelling in Earth System Models used for climate change simulations.

Your Work Environment

The Geosciences Environment Toulouse laboratory is one of the main French laboratories in earth and environmental sciences. This is the leading laboratory of the ANR-funded project PERMACHANGE (permachange.sedoo.fr ), in which the present PhD position is included.

Constraints and risks

None

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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