Interactions between paleogeography, climate and biodiversity at the geological time scale. Insights and questions from paleoclimate modelling ; Étude des liens entre paléogéographie, climat et biodiversité aux échelles de temps géologiques. Apports et questions de la modélisation des paléoclimats

My research work consists of trying to improve our knowledge of the links between the physical world and biodiversity on a geological time scale. I seek both to understand the mechanisms behind the major climate changes of the last 100 million years and to quantify their consequences on the development of biodiversity as we know it today. My presentation will initially focus on the links between palaeogeography and climate. The uplift of mountain ranges, the opening/closing of sea passages, and the break-up of supercontinents are all processes that have altered the climate system (oceanic and atmospheric dynamics in particular) over time. I will show, notably through the thesis work that I had the privilege of co-supervising, how the use of numerical climate models can (i) help to understand and quantify these processes and (ii) benefit to and from paleoclimate proxies, notably isotopic ones. By briefly presenting the development of a low-resolution version of the Earth system model of the Pierre Simon Laplace Institute (IPSL-CM5A2), I will also discuss the limits of these models for studying ancient climates, and will try to discuss their necessary evolution. Finally, I will outline my research project for the coming years, in particular the question of the bridge between geosciences and the problems of macro-evolution of biodiversity. In particular, I will look at methods of integrating spatialised paleoclimatic information into models of diversification of living organisms and how to take into account the feedback of biological evolution on climate. ; Mon travail de recherche consiste à tenter d’améliorer notre connaissance des liens entre le monde physique et la biodiversité à l’échelle des temps géologiques. Je cherche à la fois à comprendre et spatialiser les mécanismes à l’origine des grands changements climatiques des 100 derniers millions d’années, et à quantifier leurs conséquences sur la mise en place de la biodiversité telle que nous la connaissons aujourd’hui. Mon exposé se concentrera dans un ...