Articles | Volume 7, issue 2
https://doi.org/10.5194/wcd-7-843-2026
© 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-7-843-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Dry and moist convective upper bounds for near-surface temperatures
Quentin Nicolas
CORRESPONDING AUTHOR
Institute for Atmospheric and Climate Science, ETH Zürich, Zürich, Switzerland
Belinda Hotz
Institute for Atmospheric and Climate Science, ETH Zürich, Zürich, Switzerland
Related authors
Quentin Nicolas and William R. Boos
Weather Clim. Dynam., 6, 231–244, https://doi.org/10.5194/wcd-6-231-2025, https://doi.org/10.5194/wcd-6-231-2025, 2025
Short summary
Short summary
Rainfall in mountainous regions constitutes an important source of freshwater in the tropics. Yet how it will change with global warming remains an open question. Here, we reveal a strong sensitivity of this rainfall to the speed of prevailing winds. This relationship, validated by theory, simulations, and observational data, suggests that regional wind shifts will significantly influence future rainfall changes in the tropics.
Belinda Hotz, Heini Wernli, Matthias Röthlisberger, and Robin Noyelle
EGUsphere, https://doi.org/10.5194/egusphere-2026-1522, https://doi.org/10.5194/egusphere-2026-1522, 2026
Short summary
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We systematically investigate vertical temperature anomaly profiles during heat extremes on a global scale. Three distinct clusters emerge, aligning closely with the polar, mid-latitude, and tropical climate zones and capturing the key characteristics of the vertical profiles. While mid-latitude and polar profiles feature anomalies throughout the troposphere, with the highest temperature anomalies in the boundary layer, tropical temperature anomalies are confined to the boundary layer.
Quentin Nicolas and William R. Boos
Weather Clim. Dynam., 6, 231–244, https://doi.org/10.5194/wcd-6-231-2025, https://doi.org/10.5194/wcd-6-231-2025, 2025
Short summary
Short summary
Rainfall in mountainous regions constitutes an important source of freshwater in the tropics. Yet how it will change with global warming remains an open question. Here, we reveal a strong sensitivity of this rainfall to the speed of prevailing winds. This relationship, validated by theory, simulations, and observational data, suggests that regional wind shifts will significantly influence future rainfall changes in the tropics.
Belinda Hotz, Lukas Papritz, and Matthias Röthlisberger
Weather Clim. Dynam., 5, 323–343, https://doi.org/10.5194/wcd-5-323-2024, https://doi.org/10.5194/wcd-5-323-2024, 2024
Short summary
Short summary
Analysing the vertical structure of temperature anomalies of recent record-breaking heatwaves reveals a complex four-dimensional interplay of anticyclone–heatwave interactions, with vertically strongly varying advective, adiabatic, and diabatic contributions to the respective temperature anomalies. The heatwaves featured bottom-heavy positive temperature anomalies, extending throughout the troposphere.
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Short summary
Heatwaves are intensifying at a fast pace, and how much further they can strengthen is unknown. Our study seeks to estimate a physical upper limit to surface air temperature. We show that, unlike what recent work suggested, the intensity of the most extreme heatwaves may not be constrained by the onset of thunderstorms. Instead, the limit is set by the development of a several-kilometer-deep layer of well-mixed air above the ground, and modulated by a very hot and unstable near-surface layer.
Heatwaves are intensifying at a fast pace, and how much further they can strengthen is unknown....