[PDE & Applications seminar] Kerstin Lux-Gottschalk: The effect of parameter uncertainty on climate tipping points

05 October 2023 16:00 till 17:00 - Location: Snijderszaal 36.LB 01.010 EEMCS | Add to my calendar

Several subsystems of the Earth might undergo critical transitions under sustained anthropogenic forcing, i.e. these systems are at risk of passing a so-called tipping point (TP). That induces a drastic sudden change in the system’s phase portrait that is often irreversible. We approach these tipping phenomena through the lense of nonlinear dynamical systems theory. In particular, we use tools from bifurcation theory, which provides the mathematical framework for the creation and loss of equilibria as well as changes in their stability properties under variation of a deterministic control parameter. In this talk, I will address the question how uncertainty in model parameters affects the tipping behavior of the dynamical system in terms of the location of TPs and how they are approached. I will present a workflow for climate tipping points from a Bayesian inference on the uncertain model input parameter to the forward propagation of the obtained input probability distribution through the nonlinear dynamics turning the bifurcation curve into a random object [1]. I will show numerical results on a conceptual model of the Atlantic Meridional Overturning Circulation, which is one of the identified tipping elements. This talk covers joint work with Peter Ashwin (University of Exeter, UK), Richard Wood (Met Office, UK), and Christian K ̈uhn (Technical University of Munich, Germany).