Dynamically downscaled seasonal heat wave projections in the CONUS

Journal Article · Sun Jun 01 00:00:00 UTC 2025 · npj Climate and Atmospheric Science

DOI: https://doi.org/10.1038/s41612-025-01055-3 · OSTI ID:2572197

Rubin, Hannah ^[1]; Zhang, Leyuan ^[1]; Fu, Joshua S. ^[1]; Rastogi, Deeksha  ^[2]; Kao, Shih-Chieh  ^[2]; Ashfaq, Moetasim  ^[2]

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1. University of Tennessee, Knoxville (UTK)
2. ORNL

Heat waves are a well-documented hazard that are projected to increase in intensity, duration, and frequency with climate change. Regions of the US experience widely varying temperatures; for example, 35 °C is extremely hot for spring in the Northeast but not for summer in the Southeast. It is important to evaluate projections within a regional context and at a high enough resolution to understand the risks to populations. We identify heat waves across the Conterminous US (CONUS) under SSP5–8.5 from 2020 to 2059 with an ensemble of dynamically downscaled Coupled Model Intercomparison Project Phase 6 (CMIP6) model outputs. We demonstrate that there are regional differences caused by seasonal and local drivers of persistent hot temperatures. Summer heat waves are increasing in intensity and duration faster than winter heat waves because of the atmospheric conditions that promote these events. Our analysis emphasizes the value of fine-resolution modeling for projecting future climate risks.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE; USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 2572197
• Journal Information: npj Climate and Atmospheric Science, Journal Name: npj Climate and Atmospheric Science Journal Issue: 1 Vol. 8
• Country of Publication: United States
• Language: English