1.2. The Atmosphere
The atmosphere is a mixture of different gases and aerosols (suspended liquid and solid particles) collectively known as air which envelopes the Earth, forming an integrated environmental (climate) system with all the Earth's components. The atmosphere provides various functions, not least the ability to sustain life. Of prime interest for a discussion on climate change, however, is its ability to control the Earth's energy budget. To understand this process, it will be necessary to study in more detail the composition of the atmosphere.