Cirrus, Stratus, Cumulus and Cumulonimbus Types of Clouds Cirrus, Stratus, Cumulus and Cumulonimbus

A. What causes clouds to form? 1. There must be three main ingredients present in order for clouds to form: A. Moisture - There must be sufficient water vapor in the air to build a cloud. B. Cooling air - The air temperature must decrease enough for water vapor to condense and form droplets. C. Condensation nuclei - Tiny particles, invisible to the human eye, such as dust, dirt, and pollutants, provide surfaces on which water molecules can gather and condense into water droplets.

B. Cirrus Clouds 1. Typically found at high altitudes. 2. Thin wispy clouds 3. Cirrus clouds are composed of ice crystals that originate from the freezing of super cooled water droplets. 4. Cirrus generally occur in fair weather and point in the direction of air movement at their elevation.

E. Cumulonimbus Clouds Cumulonimbus clouds are different because they cannot be classified as low, middle or high altitude clouds. These are often storm clouds which can be ten or more miles in height, extending through all the levels of altitude. They are very tall clouds. 3. Cumulonimbus clouds can produce rain showers, snow showers, hail, or even thunderstorms.

Cumulonimbus

D. Cumulus Clouds The word cumulus comes from Latin, “means heap or pile”. 1.Cumulus clouds are usually puffy with distinct edges and usually a noticeable vertical (upward) development. 2. Cumulus clouds are sometimes associated with thunderstorms.

C. Stratus Clouds 1. Stratus clouds are usually low clouds seen on an overcast day. 2. Stratus clouds often block out the sun. 3. Usually produce light to heavy continuous rain. 4. Fog can be considered a low stratus cloud

Animations CLOUDS http://asdwww.larc.nasa.gov/SCOOL/tutorial/clouds/cloudtypes.swf SCIENCE ANIMATIONS http://www.educypedia.be/education/climateanimations.htm