Breaking through the barrier of time integration for climate and weather simulations (Martin Schreiber, Université de Grenoble)

10.12.2024 14:00 – 15:00

Weather and climate simulations face new challenges due to changes in computer architectures caused by physical limitations. From a pure computing perspective, algorithms are required to cope with stagnating or decreasing per-core speed and increasing on-chip parallelism. These and other showstopping trends will continue and already led to research on partly disruptive mathematical and algorithmic reformulations of dynamic cores, e.g., using (additional) parallelism along the time dimension.

This presentation provides an overview and introduction of a selection of the following promising newly developed and evaluated time integration methods for equations related to prototypical dynamical cores, all aimed at improving the ratio of wall clock time vs. error: Exponential Integration, Rational Approximation of Exponential Integration (REXI), Parallel Full Approximation Scheme in Space and Time (PFASST), Semi-Lagrangian methods combined with Parareal and MultiGrid Reduction In Time (MGRIT). We get improved time-vs.-error rates, but sometimes with additional challenges on the way which need to be further overcome. Overall, our results motivate further investigation and combination of these methods for operational weather/climate systems.


I gratefully acknowledge collaborators related to this presentation:
Jed Brown, Finn Capelle, Francois Hamon, Richard Loft, Michael Minion, Nathanael Schaeffer, Andreas Schmitt, Joao G.C. Steinsträsser, Pedro S. Peixoto, Raphael Schilling

Lieu

Bâtiment: Conseil Général 7-9

Room 1-05, Séminaire d'analyse numérique

entrée libre