Abstract: ""The Arctic has seen dramatic changes in recent decades. Here we use a simple metric, the Arctic residence time of air, that is, the time air spends uninterruptedly north of 70◦N, to evaluate how these changes have affected the high-latitude atmospheric circulation in the last 40 years. We find that, on average, near-surface air resides between 7 (winter) and 12 (summer) days in the Arctic. This residence time has decreased almost year-round since the 1980s, especially pronounced in the seasonal transition periods (fall: − 0.9 day; spring: − 1.4 days). The more pronounced reduction in spring also affects higher atmospheric layers. Our analysis indicates that this reduction is likely linked to the observed sea ice loss, decrease in snow cover, and increase in temperature. Furthermore, it indicates a speed-up of the circulation, effectively making the Arctic less isolated and more prone to influences from mid-latitudes."