The effects of climate change are directly felt and experienced through the increased occurrence and magnitude of extreme weather and climate events, which inflict damage and harm on societies and natural systems.

Understanding physical processes by which extreme events such as heatwaves, heavy precipitation or tropical cyclones emerge and change their statistics in response to anthropogenic warming is imperative for climate risk stress testing and effective adaptation measures.

Trends and changing dependence structures of independent and connected climate impact drivers can lead to new, compounding and more complex climate risks some of which are currently underestimated.

In this theme we will reduce uncertainty about future risks from extreme weather and climate events by:

  • understanding physical processes that lead to extreme weather and climate events by using observational and globally gridded climate data, to benchmark and improve climate risk model projections.
  • attributing observed changes in timing, location, frequency and magnitude of extreme weather and climate events to anthropogenic climate change and disentangle the forced signal from natural variability.
  • estimating impacts from extreme weather and climate events on various societal sectors such as global food systems and human health to identify global hotspots and regions most at risk.
  • application and development of advanced statistical methods such as causal inference and explainable artificial intelligence for the to support the development of climate impact emulators and more regional and accurate risk assessment by down-scaling, and bias adjustment of model estimates.

Current collaborative Projects and Initiatives

Acute Physical Risk Assessments for the NGFS

The Network for Greening the Financial System (NGFS) facilitates managing climate-related risks in the financial sector and promotes a sustainable economy. With over 90 central banks and financial market supervisors, the network collaborates with scientific experts. In collaboration with project partners, IIASA provides the acute physical climate risk indicators and projections for different scenarios.

PERSEVERE II

The subproject PERSEVERE 2 is part of the ClimXtreme Consortium and investigates Europes increasingly persistent hot and dry summers. Changes in atmospheric dynamics, such as more frequent double jet conditions over Eurasia, have been linked to heatwaves in western Europe, explaining their accelerated trend (Rousi et al. 2022). These atmospheric changes under climate change add significant uncertainty in predicting future extreme events.  PERSEVERE II evaluates general circulation models' ability to (i) reproduce observed double jet patterns and trends, (ii) projects changes in double jet frequency under global warming and their impact on future European hot and dry conditions, and (iii) assesses extreme risks from drought and compound extremes driven by jet stream dynamics to reduce uncertainty of extreme hot and dry risks

Risk Knowledge Action Network (Risk-KAN)

Extreme weather events, associated disasters, and emergent risks pose an existential crisis to humanity and impede progress towards the Sustainable Development Goals (SDGs). Despite limiting global warming to under 2°C, the societal and ecological effects of climate change extremes will be substantial.

The Knowledge-Action Network (KAN) on Emergent Risks and Extreme Events serves as a comprehensive inter- and transdisciplinary hub for scientists, experts, and communities focusing on multi-hazard risks, disaster risk reduction, and governance of extreme events. As a Future Earth Global Research Network (GRN) and a joint initiative of the Future Earth, IRDR, WCRP, and WWRP programs, the Risk KAN actively promotes the exchange of information, knowledge, and data. The aim of the RISK KAN is to understand and reduce disaster risks under environmental change by offering global leadership in understanding and addressing emergent systemic risks and extreme events.

Publications

  • Kornhuber, K., Coumou, D., Vogel, E., Lesk, C., Donges, J. F., Lehmann, J., & Horton, R. M. (2020). Amplified Rossby waves enhance risk of concurrent heatwaves in major breadbasket regions. Nature Climate Change, 10(1), 48–53. https://doi.org/10.1038/s41558-019-0637-z
  • Rousi, E., Kornhuber, K., Beobide-Arsuaga, G., Luo, F., & Coumou, D. (2022). Accelerated western European heatwave trends linked to more-persistent double jets over Eurasia. Nature Communications, 13(1), 3851. https://doi.org/10.1038/s41467-022-31432-y
  • Raymond, C., Horton, R. M., Zscheischler, J., Martius, O., AghaKouchak, A., Balch, J., Bowen, S. G., Camargo, S. J., Hess, J., Kornhuber, K., Oppenheimer, M., Ruane, A. C., Wahl, T., & White, K. (2020). Understanding and managing connected extreme events. Nature Climate Change, 10(7), 611–621. https://doi.org/10.1038/s41558-020-0790-4
  • Kornhuber, K., Lesk, C., Schleussner, C. F., Jägermeyr, J., Pfleiderer, P., & Horton, R. M. (2023). Risks of synchronized low yields are underestimated in climate and crop model projections. Nature Communications, 14(1), 3528. https://doi.org/10.1038/s41467-023-38906-7
  • Kornhuber, K., & Tamarin-Brodsky, T. (2021). Future Changes in Northern Hemisphere Summer Weather Persistence Linked to Projected Arctic Warming. Geophysical Research Letters, 48(4), e2020GL091603. https://doi.org/10.1029/2020GL091603
  • Lembo, V., Bordoni, S., Bevacqua, E., Domeisen, D. I. V., Franzke, C. L. E., Galfi, V. M., Garfinkel, C., Grams, C. I., Hochman, A., Jha, R., Kornhuber, K., Kwasniok, F., Lucarini, V., Messori, G., Pappert, D., Perez-Fernandez, I., Riboldi, J., Russo, E., Shaw, T. A., … Zagar, N. (2024). Dynamics, statistics and predictability of Rossby waves, heatwaves and spatially compounded extreme events. https://doi.org/10.1175/BAMS-D-24-0145.1
  • Bartusek, S., Kornhuber, K., & Ting, M. (2022). 2021 North American heatwave amplified by climate change-driven nonlinear interactions. Nature Climate Change, 12(12), 1143–1150. https://doi.org/10.1038/s41558-022-01520-4
  • Kornhuber, K., & Messori, G. (2023). Recent Increase in a Recurrent Pan-Atlantic Wave Pattern Driving Concurrent Wintertime Extremes. https://doi.org/10.1175/BAMS-D-21-0295.1
  • Loriani, S., Aksenov, Y., Armstrong McKay, D., Bala, G., Born, A., Chiessi, C. M., Dijkstra, H., Donges, J. F., Drijfhout, S., England, M. H., Fedorov, A. V., Jackson, L., Kornhuber, K., Messori, G., Pausata, F., Rynders, S., Salée, J.-B., Sinha, B., Sherwood, S., … Tharammal, T. (2023). Tipping points in ocean and atmosphere circulations. EGUsphere, 1–62. https://doi.org/10.5194/egusphere-2023-2589
  • Kornhuber, K., Bartusek, S., Seager, R., Schellnhuber, H. J., & Ting, M. (2024). Global emergence of regional heatwave hotspots outpaces climate model projections. https://eartharxiv.org/repository/view/7223/
  • Perkins-Kirkpatrick, S., Barriopedro, D., Jha, R., Wang, L., Mondal, A., Libonati, R., & Kornhuber, K. (2024). Extreme terrestrial heat in 2023. Nature Reviews Earth & Environment, 5(4), 244–246. https://doi.org/10.1038/s43017-024-00536-y
  • Dolk, M., Mahul, O., Ceglar, A., & Kornhuber, K. (n.d.). Compound Risks: Implications for Physical Climate Scenario Analysis. NGFS. NGFS Scenarios Workstream
  • Reichstein, M., Benson, V., Camps-Valls, G., Boran, H., Fearnley, C., Kornhuber, K., Rahaman, N., Schöllkopf, B., Tárraga, J. M., Vinuesa, R., Blunk, J., Dall, K., Denzler, J., Frank, D., Martini, G., Nganga, N., & Robinson, D. M. (2024). Early warning of complex climate risk with integrated artificial intelligence. https://doi.org/10.21203/rs.3.rs-4248340/v1