What Are Clouds And What Are Their Types?

Clouds are classified into 10 main types, according to height and appearance. High altitude clouds are wispy and thin and composed of ice crystals, with their bases 16,000-39,000 ft. Above ground. Mid-level clouds are sheet or lump-like and are 6,500-16,000. Low-lying clouds, below 6,500 ft. Are mound-like or form sheets. The different cloud types are:  Cirrostratus, cirrus, cirrocumulus, altostratus, cumulonimbus, altocumulus, stratocumulus, cumulus, nimbostratus, stratus.

Atmospheric pressure decreases with height above the earth. When air rises, it moves to regions of lower pressure and it therefore expands. The energy needed for expansion comes from the air and it therefore cools. When air cools, it can hold less water vapour, and water vapour condenses in tiny of water as clouds. The factors that cause air to rise are:
Air may be forced if it meets hills
Convection currents carry air upwards
When warm and cold fronts meet, air is forced upwards.
Could are divided into three main groups
Cirrus clouds are delicate, white, wispy clouds which form at high levels (6000 m). They are called "mares' tails" and can extend to form a thin veil of white cloud. They don no t produce rain.
Stratus clouds. Are uniform layers of cloud, like fog, formed at 2500-6000 m. they can develop nimbostratus clouds, large flat-topped clouds shaped like a blacksmiths anvil. These produce rain.
Cumulus clouds: are "piles" of thick, lumpy, dome-shaped or cauliflower-shaped clouds with flat bases, which from at levels (below 2500m). Light cumulus clouds may give a little rain or none at all. Large cumulus produces light showers. They can grow into to become anvil-shaped cumulonimbus clouds which give heavy showers and thunderstorms.