Le changement climatique est actuellement l'un des défis majeurs de notre société. Les observations des intervalles de temps passés marqués par des instabilités climatiques et environnementales sont cruciales pour prédire les conséquences du réchauffement climatique actuel et les mécanismes de rétroaction qui permettraient à la biosphère de revenir à des conditions d'équilibre.
L'originalité et les aspects innovants de RECOVERY se construisent à l'intersection d'outils analytiques avancés et de concepts théoriques pour fournir une compréhension complète sans précédent des mécanismes de rétroaction impliqués dans la récupération du système terrestre après des changements paléoclimatiques et paléoenvironnementaux extrêmes.


RECOVERY – Response of Earth system to extreme palaeoclimatic and palaeoenvironmental changes : A multiproxy study of the aftermath of the Toarcian hyperthermal


Key information / Informations

•    Funding programme / Programme de financement: H2020-MSCA-IF-2019
•    Coordinator / Coordinateur: Guillaume SUAN - UCBL
•    Budget : 184 707,84 €
•    Grant / Subvention : 184 707,84 €
•    Début – Fin : 18/01/2021 – 17/01/2023

Context / Contexte

Over the last decades, climate change has become one of the major challenges for our society. In this context, it appears crucial to have a better understanding of Earth system dynamics, in order to predict the consequences of current climate change, and thus implement the future strategies of mitigation and adaptation. It is widely recognised that anthropogenic emissions of greenhouse gases, such as carbon dioxide (CO2), have a direct impact on climate system, and thus on the Earth’s natural greenhouse effect. Current global warming is already severely affecting physical and biological systems, and there is alarming evidence that Earth system is witnessing a sixth mass extinction. Additionally, the massive use of fertilizers is currently favouring eutrophication processes and the formation of dead anoxic zones in lakes and coastal marine environments. The causes and mechanisms triggering current climate change and environmental perturbations are relatively well understood, but there are still large uncertainties concerning the future climatic evolution, the exact consequences, and the feedbacks mechanisms that would allow the biosphere to recover and return to steady-state conditions.

Objectives / Objectifs

The overall objective of RECOVERY is to give a holistic appraisal of the palaeoclimatic and palaeoenvironmental evolution in the aftermath of the T-OAE, and of the feedback mechanisms, which have allowed the biosphere to recover. As such, this project will fill a gap in our understanding of the response of Earth system to extreme conditions, taking the aftermath of the T-OAE hyperthermal as a case study. Specific objectives aim to answer the following questions:
1) What were the carbon cycle dynamics in the aftermath of the T-OAE?
•    Specific objective: provide a high-resolution carbon-isotope stratigraphy for the middle–late Toarcian time interval, trace carbon cycle dynamics, and distil out global from regional driving mechanisms.
2) What was the palaeoclimatic evolution in the aftermath of the T-OAE hyperthermal?
•    Specific objective: reconstruct the palaeoclimatic conditions in the aftermath of the T-OAE hyperthermal, evaluate the role of these climatic conditions in modulating the palaeoenvironmental conditions, and better constrain the climate-carbon cycle feedbacks.
3) How was the level of nutrients in the aftermath of the T-OAE?
•    Specific objective: determine the flux of nutrients and changes in primary productivity.
4) Did renewed volcanic activity during the middle–late Toarcian have any influence on the palaeoenvironmental conditions?
•    Specific objective: track volcanic activity and test the potential causality link between volcanic activity and the palaeoenvironemental changes.
5) Was continental weathering efficient enough to terminate the T-OAE?
•    Specific objective: constrain continental weathering rates, and evaluate the potential impact on global climate.

Expected impact and results / Impact et résultats attendus

The originality and innovative aspects of RECOVERY builds at the intersection of advanced analytical tools and theoretical concepts to provide an unprecedented comprehensive understanding of the middle–late Toarcian time interval. RECOVERY will improve our knowledge of Earth system’s dynamics by studying a key period in the aftermath of one of the most extreme episodes of climatic and environmental changes that occurred during the Phanerozoic. The climatic and environmental evolution in the aftermath of the T-OAE is so far poorly constrained due to the relative scarcity of multi-proxy datasets available for the middle–late Toarcian compared to the early Toarcian (T-OAE). The sections that will be examined in this project will fill this gap.

LIP’s contribution / Rôle de LIP :

Follow-up of the project, administrative and financial follow-up, justification of expenses.