Brain Pop:Clouds

Cloud Types

18.3

18.3 Types of Clouds•Clouds are classified based on how they formed and their height•3 basic forms…

• Seen in fair weather, but can mean rain or snow is coming

Cirrus: (= a curl of hair) Thin, white, wispy, feathery

• Made from ice crystals at high altitudes

• Usually mean fair weather

Cumulus: (= a pile) Rounded, thick, puffy masses

• Formed by vertically rising air currents

• Block out sunlight - associated with rain

Stratus: (= a layer) Layered, gray, and smooth

• Form in sheets at low altitudes

• 3 levels of height can have seasonal and latitudinal variation

High Clouds: (above 6000 meters)

Cirrus cirrocumulus

cirrostratusCirrostratus halo around the sun

Middle Clouds: (2000-6000 meters)

altocumulus

altostratus

Low Clouds: (below 2000 meters)

nimbostratus

Stratus stratocumulus

Clouds of vertical development: (start at 2000 meters – mid/high)

cumulonimbus

Fog: A cloud with its base at or very near the ground

• The only difference between clouds and fog is their method and place of formation.

Fogs caused by cooling

Ex: coastal California

• Fog forms when warm oceanic air moves over a cold water current, then wind blows it over land

• OR fog forms over land as air temperature near the ground drops overnight and reaches the dew point in the early morning

• Fog forms over water when water temperatures are still warm, but air temperatures have fallen rapidly

• Fall and early winter

Fogs caused by evaporation