Penguin poop clouds are cooling Antarctica, new research finds, as ammonia aerosols from millions of penguins’ guano spark heat-shielding low clouds over the icy continent. In 2025, Helsinki and Canterbury scientists link this smelly process to the climate’s delicate balance, calling it “surprising.”

Ammonia from penguin guano triggers cloud formation, but the real twist comes from how it interacts with sulfur from ocean algae. This chemical synergy, observed by 7 researchers, means colonies covering square miles could shift cloud cover—turning the birds’ bathroom breaks into unexpected climate guardians.

A single large penguin colony can produce several hundred tons of guano annually—enough to spot from space.