The ozone layer is a layer of ozone gas around 20-30 km up in the stratosphere, and is of crucial importance in protecting life on Earth from harmful UV-B radiation from the sun. Every southern spring a large hole develops in this layer over Antarctica, however this year’s hole is the largest since 2008. How does the hole form and how important is this year’s growth?
Ozone is a gas consisting of three oxygen atoms in a molecule instead of the usual two. It is formed in the stratosphere when incoming ultraviolet radiation from the sun breaks up normal oxygen molecules (O2) into two single oxygen atoms. These atoms are very reactive and quickly react with another oxygen molecule to form an ozone molecule (O3).