By: Vivian Greene and Cloudia Wittich 2009 By: Vivian Greene and Cloudia Wittich

What are clouds? Clouds are water droplets or ice crystals that are in the Earths troposphere (the bottom part of the Earth's atmosphere)

Dew Point and Condensation Condensation- when water vapor becomes a liquid Dew point- temperature where water vapor condenses into a liquid. Clouds form when water vapor sticks to dust particles and condenses in the air

How do clouds form? Clouds form when the air rises. As air rises it cools. Cooler air cannot hold as much water vapor as warmer air. As the temperature reaches the dew point, the water vapor will condense on dust particles. A cloud is formed!

Formation of Clouds and Precipitation Chapter 16 Section 1 Water in the Air Formation of Clouds and Precipitation Click below to watch the Visual Concept. Visual Concept

What are the different types of clouds? Clouds are classified by their altitude and appearance (form/shape and altitude) Each type of cloud forms in a different way and brings its own type of weather There are 3 main forms of clouds The main forms are, cirrus, stratus, cumulus

Cloud Prefixes Cirro: means wisp of hair (highest clouds) Alto: means high (name given to mid-level clouds). Nimbo/nimbus: means rain. The cloud can make precipitation Cumulo: means heap. (piled-up clouds) Strato= means layer There is no prefix for low-altitude clouds

Cirrus Cirrus is Latin for curl or wisp Cirrus clouds look like curls of white hair. Very high, made of ice crystals Can indicate a change in the weather.

Stratus Stratus: Latin for sheet or layer Stratus clouds look like a gray, flat blanket that covers the entire sky. Look like fog that does not reach the ground. Usually no precipitation, but sometimes they may drizzle. Nimbostratus clouds bring rain.

Cumulus In Latin cumulus means heap Cumulus clouds look like a heap of whipped cream or cotton balls Forms on sunny days Signal good weather If it gets higher it can cause bad weather

Cumulonimbus Cumulonimbus are thunderstorm clouds. Can cause lightning, thunder, hail, strong rains, strong winds, and tornadoes. Thunderheads/anvil shape. Dense, towering storm clouds.

Common Clouds Most clouds are a mixture of the three main clouds at different altitudes Some common clouds are: Cumulo-nimbus Cirro-stratus Cirro-cumulus Alto-stratus Strato-cumulus Nimbo-stratus Fog

Cumulonimbus thunderheads thunderstorm clouds that can grow very high (over 40,000 feet) Tremendous amounts of energy are released by the condensation of water vapor inside this cloud. Lightning, thunder, and even violent tornadoes often occur with this cloud.

Cirrostratus Cirrostratus are sheet-like, high-level clouds made of ice crystals. Though cirrostratus can cover the entire sky and be up to several thousand feet thick, they are relatively transparent, as the sun or the moon can often be seen through them.

Cirrocumulus appear as small, rounded white puffs. The small ripples in these clouds resemble the scales of a fish. This sky is sometimes referred to as a "mackerel sky."

Altostratus Gray or blue-gray middle level clouds composed of ice crystals and water droplets. Often cover the entire sky. In the thinner areas of the cloud, the sun may be dimly visible as a round disk. Altostratus clouds often form ahead of storms that will produce continuous precipitation.

Stratocumulus Usually dark, heavy looking clouds. Rain is likely.

Nimbostratus Uniform dark flat low featureless clouds that make precipitation.

Fog Very low stratus cloud In contact with ground

Bibliography http://www.enchantedlearning.com/subjects/astronomy/planets/earth/clouds/ http://wxdude.com/page9.html Prentice Hall Earth Science Teacher Edition Our Textbook