Workshop on Rossby waves, heatwaves and compound extreme events

CNR-ISAC and the University of Trento are co-organizing a workshop on

 "Rossby waves, heatwaves and compound extreme events”

Synopsis

The occurrence of heatwaves in the Northern Hemisphere is often related to the persistence of a peculiar wave pattern, which affects several regions at the same time leading to “concurrent heatwaves”. These are special cases of compound extreme events, for which several indicators concur to establish the notion of extreme event, indicative of a complex process at play. Despite their large socio-economic impact, the understanding of large-scale processes leading to concurrent heatwaves is limited, yet crucial in order to better represent and predict the general circulation of mid-latitudinal atmosphere. One crucial question that remains open is the relation between surface weather extremes and circulation patterns in the atmosphere. Rossby waves are the fundamental driver of concurrent heatwaves, but are poorly predicted in models at the intraseasonal-to-seasonal timescale, mainly because of the insufficient understanding of their growth and propagation mechanisms when non-linear features characterizing the extreme events develop. We thus often resort to several diagnostic approaches, such as waveguides, local wave activity, temporal and spatial spectra, wave packets.

Furthermore, understanding the relation between Rossby waves and concurrent heat waves is crucial in terms of assessing the local impacts of climate change, given that much of this signal is predicted to increase in amplitude with global warming, and climate models are expected to correctly reproduce that.

A few years after the workshop on compound extreme events was held, we believe it is now time to bring together and enlarge the community, to review scientific advancements and identify outstanding challenges and opportunities on this very crucial topic. We welcome abstracts on the theory of concurrent heatwaves and Rossby waves, on the statistics of extreme events and their representation in models, and on the attribution of increasing frequency and intensity of extreme events to global anthropogenic climate change using different techniques.

Keynote Speakers

• Erika Coppola (ICTP, Italy);

• Daniela Domeisen (Univ. of Lausanne, Switzerland);

• Christian Franzke (IBS, S. Korea);

• Vera Melinda Galfi (VUA, Netherlands);

• Kai Kornhuber (Climate Analytics, Germany/LDEO, Columbia University, US);

• Valerio Lucarini (Univ. of Reading, UK);

• Gabriele Messori (Uppsala Univ., Sweden);

• Lenka Novak (CalTech, US);

• Jacopo Riboldi (ETH, Switzerland);

• Pascal Yiou (IPSL-LSCE, France);

• Nedjeljka Zagar (Univ. of Hamburg, Germany);

The workshop is held physically at the CNR Research Area of Bologna, Italy, from 28th to 30th November 2023, and online.