We saw in the 'basics' section that clouds are made up of millions of droplets which form as water condenses onto tiny suspended particles. In this 'read more' section on clouds we'll have a look in more detail at how these water droplets form, what happens inside clouds and how different cloud types vary.
Aerosol particles have both natural and human (anthropogenic) sources. They can be emitted directly into the air as primary aerosols or formed in the atmosphere as secondary aerosols. Different aerosols have different chemical and physical properties, some play a key role in the formation and behaviour of clouds and on the climate system and others have an impact on human health.
Clouds are composed of liquid water or ice crystals and tiny particles either inside or outside of the water droplets. These particles occur everywhere in the atmosphere, not just in the clouds. In this unit we look at the global radiation budget of the Earth and how particles affect visibility and our climate.