Clouds form when water vapor condenses into liquid water droplets or solid ice crystals. There are three main ways that air can be cooled enough for condensation to occur: contact cooling over land or sea surfaces, convection as air rises, and orographic lifting as air rises over mountains. Clouds can be classified based on their shape and height, with low-level clouds like stratus closest to the surface and high-level clouds like cirrus located over 6,000 meters. The major cloud belts around the world are associated with prevailing wind patterns.

1. Clouds John Harris - Head of Geography - Radley College - UK [email_address] http://geography.radley.org.uk

6. Cloud shapes Clouds can be classified by their shape and height Flat clouds eg Stratus (St) Fluffy clouds eg Cumulus (Cu) Wispy clouds eg Cirrus (Ci)

7. Cloud heights Clouds can also be classified by height of cloudbase Low level (below 2000m) eg stratus Middle level - alto (2,000 to 6, 000m) eg alto-cumulus High level - cirro (above 6,000m) eg cirrus

12. World cloud patterns Can you explain the major world cloud belts?