Large deviation theory applied to climate physics, a new frontier of statistical physics and applied mathematics

par Freddy Bouchet (ENS Lyon)

jeudi 16 juin 2016, 14:00 → 15:00 Europe/Paris

salle 435 (UMPA)

We will review some of the recent developments in the theoretical and mathematical aspects of the non-equilibrium statistical mechanics of climate dynamics. At the intersection between statistical mechanics, turbulence, and geophysical fluid dynamics, this field is a wonderful new playground for applied mathematics. It involves large deviation theory, stochastic partial differential equations, and diffusion Monte-Carlo algorithms. We will first present new theoretical results for the computation of the transition rates between attractors for irreversible dynamics (the non-equilibrium Eyring-Kramers law). We discuss applications to stochastic partial differntial equations that describe turbulent flows. We will then consider two classes of applications. First extreme heat waves as an example of a rare event with a huge impact. Second rare trajectories that suddenly drive the complex dynamical system from one attractor to a completely different one, related to abrupt climate changes.