A relatively thin envelope of gases, the atmosphere, plays a vital role in regulating our planet's climate and sustains life. It even helps to protect us from some of the Solar System's hazards - asteroid impacts and solar radiation.
The climate has changed repeatedly throughout Earth's history through natural processes. There is strong evidence that human activities are also affecting the climate. Visit BBC Weather for the latest climate science news and for useful background information.
The pages in this section contain interesting, fact-filled videos from popular television series such as Earth: Power of the Planet, presented by Professor Iain Stewart, and Bang Goes the Theory.
Image: The Sun shines down on a layer of clouds (credit: Aflo/naturepl.com)