the.com/ozone layer
Earth's sunscreen, made of the same gas that makes smog dangerous to breathe.
means A region of the stratosphere, roughly 15 to 35 kilometers up, where ozone gas is concentrated enough to absorb most of the sun's harmful ultraviolet radiation before it reaches the ground.
from 'Ozone' comes from the Greek 'ozein,' meaning 'to smell' — coined in the 1800s by the chemist Christian Friedrich Schönbein, who noticed a sharp odor near electrical sparks and around lightning strikes and traced it to this new form of oxygen. 'Layer' is just plain English for a stratum. The phrase 'ozone layer' itself is a 20th-century term, arriving once scientists had mapped out that the gas wasn't just a lab curiosity but formed a distinct, protective band high in the atmosphere.
- thickness
- compressed, it would be 3mm thick
- villain unmasked
- CFCs from fridges and hairspray tore holes in it
- recovery
- healing since the 1987 Montreal Protocol ban
- irony
- toxic at ground level, lifesaving 15 miles up