CLOUDS WWBAT Describe how clouds are formed and

CLOUDS

WWBAT: • Describe how clouds are formed, and practice identifying clouds.

HOW CLOUDS FORM Surface heating forms warm air below cool air. As the air rises, it goes from high to low pressure, so it expands and cools. Once the air's temperature reaches its dew point, the water vapor in it will condense.

THERE ARE 3 MAIN TYPES OF CLOUD • They are based on their shape: –Cirrus Clouds –Stratus Clouds –Cumulus Clouds

CIRRUS CLOUDS • Wispy, curly, feathery clouds • Form at high altitudes, usually above 6 km and with low temperatures • They are made of ice crystals. • They indicate fair weather

CUMULUS CLOUDS • Fluffy, lumpy, heap clouds. Looks like cotton. • These clouds usually form less than 2 km from the ground, but can extend upwards as high as 18 km. • Short cumulus clouds usually indicate fair weather. • Tall towering cumulus clouds with a flat top are called Cumulonimbus clouds. These usually produce thunderstorms. • When we see the suffix –nimbus it

STRATUS CLOUDS • These clouds form in flat layers. They usually cover all or most of the sky and are a dull gray. • These clouds may thicken and produce precipitation. Then they are called nimbostratus clouds.

THESE CLOUDS WILL OCCUR AT THREE DIFFERENT HEIGHTS • High clouds – High clouds are made up of ice crystals because high altitudes have cold temperatures. – The prefix cirro- is used to describe high clouds. • Example: Cirrocumulus

THESE CLOUDS WILL OCCUR AT THREE DIFFERENT HEIGHTS • Middle Clouds – These clouds are made up of water droplets and ice crystals. – The prefix alto- is used to describe middle level clouds. – These form between 2 and 6 km above the earth. – When we see alto- used it shows that the clouds form higher than normal, but lower than Cirrus Clouds • Example: Altocumulus and altostratus

THESE CLOUDS WILL OCCUR AT THREE DIFFERENT HEIGHTS • Low level Clouds – Low clouds are made up of water droplets. – The prefix strato- is used to describe low clouds • Example: Stratocumulus

FOG • Clouds that form near the ground. • Fog usually forms when the ground cools at night after a humid day.

WRAP-UP • Answer the following questions on a sheet of paper to be turned in. • How do clouds form? • Go to page 59 in your textbook and answer assess your understanding 1 a and 1 b.