So, what exactly is climate change? Well, the Earth retains its temperature thanks to "greenhouse" gases in the atmosphere, which trap energy from the sun. Without this greenhouse effect, the average global temperature would be more than 30°C colder than it is now.
However, every time we switch on a light, use a computer, watch television or travel by any form of motorised transport, we are creating carbon dioxide (CO2), the principal contributor to global warming. And as these polluting activities increase, the concentrations of greenhouse gases - particularly CO2 but also methane and nitrous oxide and others - build up in the atmosphere. This causes the world to heat up unnaturally, and the weather to become more extreme and unpredictable. The heating process is often referred to as global warming, and the overall effect is known as climate change.
About two-thirds of greenhouse gas pollution comes from the CO2 emitted when we burn fossil fuels such as coal, gas and oil. Coupled with this, we are also depleting the Earth's biggest natural stores of carbon - the world's forests. In combination, these factors are seriously disrupting the balance of the world's climate.
WWF-UK's climate change campaign is part of WWF's international campaign
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