Reduced air pollution is making clouds reflect less sunlight

Winter is setting in across the Northern Hemisphere, and with it, cold and cloudy winter days. Clouds play a vital role in the environment, providing rain but also reflecting sunlight before it reaches the Earth’s surface.

But between 2003 and 2022, clouds over the North Atlantic and Northeast Pacific became less reflective, allowing more sunlight to reach the ocean surface and causing sea surface temperatures to rise.