Coarse climate model grids underestimate coastal humid-heat extremes
5 affiliations
- 1Institute for Atmospheric and Climate Sciences, ETH Zürich, Zürich, Switzerland.
- 2Institut des Geosciences de l’Environnement, UGA, Saint Martin d’Heres, France.
- 3Biogéosciences, CNRS/Université de Bourgogne Europe, Dijon, France.
- 4Research Unit Sustainability and Climate Risk, Earth and Society Research Hub (ESRAH), University of Hamburg, Hamburg, Germany.
- 5ENGEOS Lab, Department of Earth Sciences, Khalifa University, Abu Dhabi, United Arab Emirates.
Abstract
Humid-heat extremes reach intensities close to the limit of human survivability around the Arabian Peninsula. Here, we analyze fully coupled kilometer-scale Icosahedral Nonhydrostatic (ICON) and Integrated Forecasting System-FinitevolumE Sea ice-Ocean Model (IFS-FESOM) simulations from the nextGEMS project, with original resolutions of around 9 kilometers, and compare them with station observations, ERA5, and CMIP6 projections. IFS-FESOM reproduces well the observed upper-tail wet-bulb temperature (TW) and lies near the high end of the CMIP6 distribution over coastal regions, while ICON simulates weaker extremes. Spatial smoothing suppresses localized coastal maxima, reducing daily-maximum TW extremes by up to 8°C and lowering exceedance frequencies across multiple thresholds. Native resolution fields also show stronger mid-century increases in exposure under SSP3-7.0 than their coarse-gridded counterparts. These results suggest that conventional coarse resolution projections may underestimate localized coastal humid-heat risk, although the magnitude of this effect remains model dependent.
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BibTeX
@article{carniel2026coarse,
title = {{Coarse climate model grids underestimate coastal humid-heat extremes}},
author = {Cosimo E. Carniel and Jonathan D. Wille and Lukas Brunner and Diana Francis and Erich M. Fischer},
journal = {Science Advances},
year = {2026},
month = oct,
doi = {10.1126/sciadv.ael4020},
url = {https://www.science.org/doi/abs/10.1126/sciadv.ael4020},
note = {CC BY},
}
RIS
TY - JOUR
TI - Coarse climate model grids underestimate coastal humid-heat extremes
AU - Cosimo E. Carniel
AU - Jonathan D. Wille
AU - Lukas Brunner
AU - Diana Francis
AU - Erich M. Fischer
PY - 2026
DA - 2026/10/30
JO - Science Advances
DO - 10.1126/sciadv.ael4020
UR - https://www.science.org/doi/abs/10.1126/sciadv.ael4020
AB - Humid-heat extremes reach intensities close to the limit of human survivability around the Arabian Peninsula. Here, we analyze fully coupled kilometer-scale Icosahedral Nonhydrostatic (ICON) and Integrated Forecasting System-FinitevolumE Sea ice-Ocean Model (IFS-FESOM) simulations from the nextGEMS project, with original resolutions of around 9 kilometers, and compare them with station observations, ERA5, and CMIP6 projections. IFS-FESOM reproduces well the observed upper-tail wet-bulb temperature (TW) and lies near the high end of the CMIP6 distribution over coastal regions, while ICON simulates weaker extremes. Spatial smoothing suppresses localized coastal maxima, reducing daily-maximum TW extremes by up to 8°C and lowering exceedance frequencies across multiple thresholds. Native resolution fields also show stronger mid-century increases in exposure under SSP3-7.0 than their coarse-gridded counterparts. These results suggest that conventional coarse resolution projections may underestimate localized coastal humid-heat risk, although the magnitude of this effect remains model dependent.
SN - 2375-2548
ER -