Modeling and simulating spatial extremes by combining extreme value theory with generative adversarial networks

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Younes Boulaguiem - , Universität Genf (Autor:in)
  • Jakob Zscheischler - , Helmholtz-Zentrum für Umweltforschung (UFZ), Universität Bern (Autor:in)
  • Edoardo Vignotto - , Universität Genf (Autor:in)
  • Karin Van Der Wiel - , Royal Netherlands Meteorological Institute (Autor:in)
  • Sebastian Engelke - , Universität Genf (Autor:in)

Abstract

Modeling dependencies between climate extremes is important for climate risk assessment, for instance when allocating emergency management funds. In statistics, multivariate extreme value theory is often used to model spatial extremes. However, most commonly used approaches require strong assumptions and are either too simplistic or over-parameterized. From a machine learning perspective, generative adversarial networks (GANs) are a powerful tool to model dependencies in high-dimensional spaces. Yet in the standard setting, GANs do not well represent dependencies in the extremes. Here we combine GANs with extreme value theory (evtGAN) to model spatial dependencies in summer maxima of temperature and winter maxima in precipitation over a large part of western Europe. We use data from a stationary 2000-year climate model simulation to validate the approach and explore its sensitivity to small sample sizes. Our results show that evtGAN outperforms classical GANs and standard statistical approaches to model spatial extremes. Already with about 50 years of data, which corresponds to commonly available climate records, we obtain reasonably good performance. In general, dependencies between temperature extremes are better captured than dependencies between precipitation extremes due to the high spatial coherence in temperature fields. Our approach can be applied to other climate variables and can be used to emulate climate models when running very long simulations to determine dependencies in the extremes is deemed infeasible.

Details

OriginalspracheEnglisch
Aufsatznummere5
FachzeitschriftEnvironmental Data Science
Jahrgang1
PublikationsstatusVeröffentlicht - 13 Apr. 2022
Peer-Review-StatusJa
Extern publiziertJa

Externe IDs

ORCID /0000-0001-6045-1629/work/197321873

Schlagworte

Ziele für nachhaltige Entwicklung

Schlagwörter

  • Climate model simulations, extreme value theory, generative adversarial networks, spatial extremes