In the heart of Europe, France is on a mission to bolster its wind power capacity, aiming to meet ambitious climate goals. Yet, as the country ramps up its reliance on wind energy, it faces an intriguing challenge: the compound impact of low-wind and cold days during winter. These events, where calm winds meet frigid temperatures, can strain the electricity grid, pushing it to its limits. A recent study, led by François Collet of the CECI, Université de Toulouse, and CERFACS–CNRS in Toulouse, France, delves into the evolution of these compound events over the past seven decades, offering insights that could reshape the energy sector’s approach to winter preparedness.
The research, published in ‘Natural Hazards and Earth System Sciences’ (translated to ‘Natural Hazards and Earth System Sciences’), reveals a complex interplay between weather patterns and energy demand. Collet and his team analyzed daily data from 1950 to 2022, identifying compound low-wind and cold events using a bottom-up approach. Their findings show a high degree of interannual variability, with some winters experiencing no such events, while others saw up to 13 days of compound stress. “The frequency of these compound events has decreased over the study period, which is likely due to a decrease in the frequency of cold days,” Collet explains. This decrease, however, is not solely attributable to anthropogenic factors, as the study suggests that atmospheric circulation and its internal variability also play a significant role.
The study further identifies four distinct weather types that lead to these compound events, each with unique synoptic situations. One particularly notable weather type is characterized by pronounced positive mean sea-level pressure anomalies over Iceland and negative anomalies west of Portugal. This configuration limits the entrance of westerlies, inducing a north-easterly flow that brings cold air over France and Europe. “This weather type is associated with the highest frequency of compound events,” Collet notes, highlighting the critical role of large-scale circulation patterns in shaping these energy challenges.
As France and other European countries continue to invest in wind power, understanding these compound events becomes crucial. The findings suggest that while the overall trend shows a decrease in cold days, the role of atmospheric circulation in the observed decrease in compound events remains complex and warrants further investigation. This research could influence future developments in the energy sector, particularly in the realm of grid management and renewable energy integration. Energy providers may need to adapt their strategies, investing in diverse energy sources and advanced grid technologies to mitigate the risks posed by these compound events. As the energy landscape evolves, so too must our understanding of the weather patterns that shape it.
