Articles | Volume 7, issue 1
https://doi.org/10.5194/wcd-7-393-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wcd-7-393-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Constructing extreme heatwave storylines with differentiable climate models
Tim Whittaker
CORRESPONDING AUTHOR
Centre Étude et simulation du climat à l'échelle régionale (ESCER), Département des Sciences de la Terre et de l’Atmosphère, Université du Québec à Montréal, Montréal, Québec, Canada
Alejandro Di Luca
Centre Étude et simulation du climat à l'échelle régionale (ESCER), Département des Sciences de la Terre et de l’Atmosphère, Université du Québec à Montréal, Montréal, Québec, Canada
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Clarence Gagnon, Daniel F. Nadeau, Alejandro Di Luca, Benoit Brault, Romane Hamon, Nicolas L. Roy, Marc-André Bourgault, and François Anctil
EGUsphere, https://doi.org/10.5194/egusphere-2025-6192, https://doi.org/10.5194/egusphere-2025-6192, 2026
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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This article studies the contribution of extratropical cyclones to nearly 500 river floods that caused material damage in the province of Quebec, in eastern Canada, between 1991 and 2020. By bringing significant amounts of precipitation, extratropical cyclones played a key role in the majority of floods. During the period, over half of the flood-contributing storms originated in the central United States and the Gulf of Mexico, and just a handful caused most of the financial damage observed.
François Roberge, Alejandro Di Luca, René Laprise, Philippe Lucas-Picher, and Julie Thériault
Geosci. Model Dev., 17, 1497–1510, https://doi.org/10.5194/gmd-17-1497-2024, https://doi.org/10.5194/gmd-17-1497-2024, 2024
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Our study addresses a challenge in dynamical downscaling using regional climate models, focusing on the lack of small-scale features near the boundaries. We introduce a method to identify this “spatial spin-up” in precipitation simulations. Results show spin-up distances up to 300 km, varying by season and driving variable. Double nesting with comprehensive variables (e.g. microphysical variables) offers advantages. Findings will help optimize simulations for better climate projections.
Olivier Asselin, Martin Leduc, Dominique Paquin, Katja Winger, Alejandro Di Luca, Melissa Bukovsky, Biljana Music, and Michel Giguère
EGUsphere, https://doi.org/10.5194/egusphere-2022-291, https://doi.org/10.5194/egusphere-2022-291, 2022
Preprint archived
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Planting trees cools the climate by removing CO2 from the atmosphere, but may also cool or warm the climate by altering the albedo, roughness and evapotranspiration efficiency of the surface. To quantify these biogeophysical effects, we ran regional climate models over two idealized worlds, FOREST and GRASS, respectively representing maximum and minimum tree cover over North America and Europe. We find that these effects must be taken into account to successfully mitigate climate change.
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Short summary
Heatwaves are becoming more extreme in frequency and intensity. Yet running many climate simulations to find the rare worst-case events is slow and costly. We developed a method that tweaks initial weather conditions to target the most extreme heat scenarios at a fraction of the usual cost. For the 2021 Pacific Northwest heatwave, it found cases up to 3.7 °C hotter than any run in a 75-member ensemble, helping communities prepare for the worst.
Heatwaves are becoming more extreme in frequency and intensity. Yet running many climate...