There's a new hole in the ozone layer, and it's not where you would expect it to be.
Scientists have monitored the infamous ozone hole in Antarctica since the 1980s, but a mini hole opened up on the other side of the planet in the Arctic this year. The European Space Agency announced the discovery on Monday.
NASA has likened the ozone layer to atmospheric sunscreen. It protects Earth from the sun's ultraviolet radiation and helps keep our planet habitable for life. The emergence of the Antarctica hole sparked a global effort to reduce the use of chemicals, including some aerosol products, that contribute to the hole.
German Aerospace Center (DLR) researchers watched the Arctic hole's formation by using data from the Copernicus Sentinel-5P satellite. The Antarctica hole forms seasonally, but Arctic holes, particularly of this size, are a rare occurrence.
ESA said "unusual atmospheric conditions" are to blame, including freezing temperatures in the stratosphere, an extremely strong polar vortex (a swirling expanse of cold air) and the arrival of post-winter sunlight.