The climate has changed naturally throughout the Earth’s history. But natural causes cannot explain the particularly rapid warming seen over the last century, according to the UN’s climate body, the Intergovernmental Panel on Climate Change (IPCC).
This warming has been caused by human activities, mainly the widespread use of fossil fuels – coal, oil and gas – in homes, factories and transport systems.
When fossil fuels burn, they release greenhouse gases – mostly carbon dioxide (CO2). This CO2 acts like a blanket, trapping extra energy in the atmosphere near the Earth’s surface. This causes the planet to heat up.
Since the start of the Industrial Revolution – when humans started burning large amounts of fossil fuels – the amount of CO2 in the atmosphere has risen by about 50%, external, far above levels seen in the Earth’s recent history.
The CO2 released from burning fossil fuels, external has a distinctive chemical fingerprint. This matches the type of CO2 increasingly found in the atmosphere.