EMS – ACAM Webinar: What Caused the Unusual European Winter of 2025?
Internal Variability, Teleconnections, and the Role of Climate Change
This webinar will be held as Google meet webinar:
- Speaker: Bernat Jiménez Esteve, Instituto de Geociencias – IGEO
- Day & time: Thursday, 9 July 2026 at 7pm CEST
- Registration is not required. This will become the link to join the event directly
Note that this webinar takes place on a Thursday in the evening, and starts at 7pm CEST!
Abstract
The recent winter of 2025/26 has been characterised by an active Atlantic storm season, with a persistent sequence of high-impact storms affecting western Europe. Several of these systems were associated with atmospheric rivers, which channelled large amounts of moisture towards the continent and produced repeated episodes of heavy rainfall and flooding. The accumulated effect of these successive events led to unusually wet conditions across large parts of western Europe. In several regions, national meteorological services reported record-breaking or near-record precipitation totals, underlining the exceptional character of the season.
In this talk, we will assess how unusual this past winter has been from both precipitation and circulation perspectives. We will analyse the circulation drivers behind this sequence of storms and heavy rainfall events, focusing on large-scale modes of variability, weather regimes, and the jet-stream behaviour over the North Atlantic–European sector. We will also examine the role of stratospheric variability and regional and remote sea-surface temperature anomalies. Finally, we will evaluate how anthropogenic climate change may have affected the likelihood and severity of these events, separating robust thermodynamic contributions to moisture availability and precipitation from more uncertain dynamical influences related to North Atlantic circulation and storm-track variability.
About the speaker
Bernat Jiménez Esteve is an atmospheric scientist working at the intersection of atmospheric dynamics, climate variability, numerical modelling, and artificial intelligence applied to weather and climate research.
After training in Physics and Meteorology at the University of Barcelona, he earned his PhD in Atmospheric and Climate Science from ETH Zurich, Switzerland, in 2019. He is currently a postdoctoral researcher at the Institute of Geosciences (IGEO, CSIC-UCM) and an Adjunct Professor at the University of Barcelona.
His research has focused on the dynamical drivers of climate variability and extreme events, including the remote influence of El Niño on European climate and the atmospheric mechanisms controlling the intensity and persistence of heatwaves. He has worked at GEOMAR, ETH Zurich, Meteomatics AG, and the Barcelona Supercomputing Center, contributing to the development and evaluation of high-resolution weather and climate models.
His current work investigates how newly developed artificial-intelligence-based weather prediction models can be used for the attribution of extreme events to anthropogenic climate change. He is particularly interested in understanding how human-induced warming affects the likelihood, intensity, and physical drivers of extreme weather. He is involved in international initiatives, including ARIP, within the WCRP APARC programme, where he focuses on the evaluation of extreme events in reanalysis products, and LEADER, which focuses on attributing dynamically forced extreme events using large ensembles of climate simulations.
