Anthropogenic aerosols can shape the winter mid-latitude cyclone tracks

Mid-latitude cyclones are “parent storms” of various weather hazards and contribute significantly to the moisture and heat intrusion into the Arctic. Anthropogenic aerosols are known to affect cyclone intensities and their associated precipitation, but their impacts on cyclone tracks remain largely unclear. Here, based on both observational data diagnosis and global climate model simulations, we show that anthropogenic aerosols over East Asia can lead to a significant poleward drift of mid-latitude cyclone tracks in winter over the North Pacific. By suppressing precipitation in the southeastern sector of cyclones and enhancing it in the northeastern sector, aerosols increase the positive potential vorticity tendency northeast of the cyclones, thereby driving their poleward drift. This might give rise to more cyclones migrating into the Arctic over the North Pacific, reducing the Arctic sea ice extent in recent decades. In the future, efforts to reduce aerosol emissions in East Asia could potentially mitigate the poleward migration of the storm track driven by global warming.