The Earth's climate has changed many times over the course of its history. We've had ice ages and warm periods in the past, but this time it's different. The current rate of global warming is unprecedented - and it's caused by us humans.
It's all down to the greenhouse effect. When we burn fossil fuels they emit carbon dioxide which becomes part of our atmosphere. This traps heat like a blanket, warming the planet. The heat causes more water vapour to enter the air, another greenhouse gas, and the effect escalates.
Usually, nature's carbon cycle would remove the extra carbon dioxide. But we've added so much of the gas to the air that nature can't keep up. However, there are ways we can fight global warming. Have a go at this quiz and see if you know the causes of climate change and the ways we can tackle it.