Ozone Purge
From Tardis Wiki, the free Doctor Who reference
The Ozone Purge was an environmental and ecological change for the Earth. (BFA: An Earthly Child)
The purge occurred around 2106. It affected many lifeforms, causing sheep, cats and sparrows to go extinct. (NA: Lucifer Rising) It also led to the last traces of oil being found on the Earth, forcing new oil companies to start on other worlds. (BFA: An Earthly Child)
