European supercell thunderstorms-A prevalent current threat and an increasing future hazard

Area of Science:

• Meteorology and Climate Science
• Atmospheric Science
• Severe Weather Studies

Background:

• Supercell thunderstorms pose significant societal risks and are difficult to monitor comprehensively.
• Current monitoring relies on national radar networks, limiting broader European analysis.
• Understanding supercell distribution is crucial for climate adaptation and hazard mitigation.

Purpose of the Study:

• To characterize supercell thunderstorm occurrence in Europe under current and future climate conditions.
• To identify geographical areas with high supercell frequency and predict changes.
• To assess the impact of global warming on supercell distribution.

Main Methods:

• Utilized kilometer-scale climate simulations to model supercell occurrence.
• Compared current climate simulations with a +3°C global warming scenario (pseudo-global warming).
• Analyzed spatial patterns and frequency changes across Europe.

Main Results:

• Current climate simulations reveal hundreds of supercells per season, peaking near complex topography like the Alps.
• Future climate simulations indicate an average 11% increase in supercell occurrence.
• A spatial dipole in changes is observed: increases in central/eastern Europe, decreases in the Iberian Peninsula and southwestern France.

Conclusions:

• Supercell thunderstorm distribution is strongly influenced by topography and climate.
• Global warming is projected to alter supercell frequencies across Europe, with regional variations.
• These findings are critical for future severe weather preparedness and climate impact assessments.