Global warming (Encyclopaedia Britannica)
The rise of air temperatures near Earth’s surface over the past one to two centuries is known as global warming.
Earth has experienced periods of gradual warming and cooling throughout its existence as a result of natural causes. Such natural causes have included volcanic eruptions and variations in the Sun’s output. However, scientists have attributed the recent increase in global temperatures to human causes—primarily the release of certain gases into the atmosphere as a result of industrial activity. These gases are known as greenhouse gases. They absorb and trap heat emitted from Earth’s surface through a process known as the greenhouse effect.
