First steps of a historical storm track model based on climate reanalysis data for understanding the spatial footprint of recorded storm impacts

Abstract. In the context of climate change, understanding extratropical storm dynamics is crucial for anticipating risks related to sea-level rise, as coastal hazards are expected to be more frequent in the future decades. This study presents the first steps of an innovative storm track reconstruction model based on wind gusts from ERA5 reanalysis data, instead of relying solely on atmospheric pressure. By focusing on wind intensity, the model prototype enables the identification of “impact trajectories” that align more closely with observed damage along the French Atlantic coastline. The methodological framework includes four main steps: ERA5 data processing, high-wind structure detection, trajectory modeling and smoothing, and interactive mapping. To validate the approach, seven major historical storms were analyzed: Xynthia (2010), Lothar and Martin (1999), Daria and Herta (1990), the 1987 “Great Storm”, and the February 1974 event. The modeled tracks were compared with geomorphological records (sedimentary deposits and dendrochronology) and historical sources such written documents and newspapers, revealing strong spatial consistency. Results highlight the value of combining climate reanalysis data with environmental archives to better understand past storm dynamics. This interdisciplinary approach may enhance the temporal depth of storm reconstructions and can be applied to pre-instrumental periods. The early stage of this model offers significant potential for assessing long-term changes in storm patterns and shall contribute to improved projections of future coastal hazards in the ongoing context of climate change.