Subseasonal variability of the winter North Atlantic jet stream has decreased due to climate change

The North Atlantic eddy-driven jet plays a vital role in shaping Euro-Atlantic weather and climate. While previous research has focused on the seasonal mean jet response to climate change, its changes at subseasonal timescales remain poorly understood, despite the importance for extreme weather. Here, we show that over the past 75 years, wintertime subseasonal variability in jet latitude and tilt has declined by 18% and 14%, respectively. The decreased jet variability is connected to regional storm tracks, atmospheric blocking, precipitation and temperature variability in Europe. Climate models show that part of the reduction in jet variability is due to external forcing, though they tend to underestimate its magnitude. Models project that jet variability will continue to decrease throughout the 21st century under increasing global warming. These findings reveal a robust response of the North Atlantic jet to climate change with implications for current and future European weather. Anthropogenic climate change has significantly reduced the winter North Atlantic jet stream’s subseasonal variability over the past seven decades, according to climate model simulations.