Scientists have developed a new mathematical method that helps quantify how human-caused climate change is intensifying extreme weather events across Europe. The breakthrough approach, created by climate researcher Gottfried Kirchengast and colleagues at the University of Graz in Austria, provides a powerful tool for analyzing the growing hazards posed by heatwaves, floods, droughts, and other climate-driven extremes. By measuring multiple characteristics of these events—such as their frequency, duration, intensity, and geographic reach—the model allows researchers to better understand how much of the increasing damage from extreme weather events can be attributed to emission-intensive actors like governments, industries, and large corporations.
The researchers designed a mathematical framework capable of tracking the evolution of climate hazards over long time periods. When sufficient historical climate data are available, the model can examine trends year by year or decade by decade, offering insights into how climate risks evolve across regions. This ability to measure and track extreme weather events with precision is particularly valuable for climate science because it moves beyond simple observations and allows scientists to quantify the relationship between greenhouse gas emissions and the intensification of climate hazards.
To demonstrate the model’s capabilities, the research team analyzed changes in extreme heat across Austria and much of Europe. They used datasets of daily maximum temperatures spanning more than six decades, from 1961 to 2024. To determine what counts as “extreme,” the researchers defined thresholds based on temperatures exceeding the top one percent of values recorded during the baseline period from 1961 to 1990. These thresholds varied across Europe depending on local climate conditions. For example, the extreme temperature benchmark in Austria was set at 30°C, while southern Spain exceeded 35°C and Finland’s threshold was about 25°C.
The study, published in the journal Weather and Climate Extremes, revealed a dramatic increase in heat intensity across Europe. In Austria and many parts of Central and Southern Europe, the overall extremity of heat has increased roughly tenfold during the period from 2010 to 2024 compared with the historical baseline. According to Kirchengast, this rise far exceeds natural variability and provides unusually clear evidence of human influence on the climate system. The findings suggest that climate change is not only making heatwaves more common but also significantly increasing their severity and spatial extent.
The consequences of these extreme weather events are already visible across the continent. During the summer of 2025, much of Europe experienced prolonged heatwaves that pushed temperatures near or above 40°C in several countries. The heat contributed to widespread drought conditions and was linked to thousands of deaths. A study conducted by researchers from Imperial College London and the London School of Hygiene & Tropical Medicine examined 854 European cities and estimated that climate change was responsible for approximately 68 percent of the 24,400 heat-related deaths recorded during the summer. Human-driven warming increased temperatures by as much as 3.6°C in some areas, intensifying the deadly effects of the heat.
The economic costs of these climate impacts are also mounting rapidly. Europe’s extreme summer weather in 2025 caused immediate economic losses of at least €43 billion, with projections suggesting that total damages could reach €126 billion by 2029. Additional research led by the University of Mannheim and economists from the European Central Bank found that heatwaves, droughts, and floods affected roughly a quarter of all EU regions during the same summer. These extreme weather events collectively reduced economic output across the European Union by about 0.26 percent in 2024 alone.
Researchers warn that these estimates may still underestimate the true economic toll because they do not fully capture compound climate impacts, where multiple hazards occur simultaneously. For example, heatwaves often intensify drought conditions, amplifying both environmental stress and economic damage. As climate change continues to reshape weather patterns, tools like the new hazard model will play an increasingly important role in identifying responsibility, understanding risks, and guiding strategies to mitigate the growing impacts of extreme weather events.