CLOUDS Name Block Date Cloud – A collection of millions of tiny water droplets or ice crystals Humidity – The amount of water vapor or moisture in the air. Relative Humidity – The amount of humidity the air contains versus the amount it can actually hold. Condensation – Process when water vapor goes from a gas to liquid. Dew Point – The temperature the air must cool to in order to be saturated and condensation to occur.

Absolute Humidity: Maximum water vapor that air holds Relative Humidity: Actual humidity at a certain temperature

How do clouds form? CLOUD TYPES Your foldable

How do clouds form? 1. Warm air rises and cools 2. The rising air cools and becomes saturated 3. At saturation the water vapor changes to a liquid or a solid depending on the air temperature 4. Higher temperatures = Condensation of water vapor on particles, such as dust, smoke and salt, that is suspended in the air as tiny water droplets 5. Lower temperatures = Below freezing, water vapor turn into a solid, forming ice crystals

3. Precipitation Cloud Types Classifications based on: 2. Altitude 1. Shape or Form

SHAPEORFORMSHAPEORFORM DESCRIPTIONDESCRIPTION SKETCH/PHOTOSKETCH/PHOTO ALTITUDEALTITUDE Your foldable CLASSIFICATIONS

Shape or Form In 1803 Luke Howard used Latin words to CLASSIFY the 4 types of clouds: 1. Cumulus = heaped 3. Cirrus = curl of hair 2. Stratus = layered 4. Nimbo = rain Write ONLY these on your foldable

SHAPEORFORMSHAPEORFORM DESCRIPTIONDESCRIPTION SKETCH/PHOTOSKETCH/PHOTO ALTITUDEALTITUDE 1. Cumulus - heaped 2. Stratus - layered 3. Cirrus – curl of hair 4. Nimbo - rain

Puffy, white clouds that tend to have flat bottoms DESCRIPTIONS Cumulus Formed when warm air rises Indicates fair weather Other adjectives: Piled, lumpy, billowy

Stratus Other adjectives: sheets, blanket Form in layers Covers large areas of the sky Often blocks the sun or moon Formed by gentle lifting of a large mass of air FOG - stratus cloud that comes in contact with the ground

Cirrus Thin, feathery, white clouds High altitudes Formed when the wind is strong Indicated approaching bad weather Other adjectives: wispy looking, horse tails

Nimbo Nimbostratus clouds are dark stratus cloud that produce light to heavy continuous rain Cumulonimbus clouds are cumulous clouds that form thunderstorms and produce heavy rain When nimbo or nimbus is part of the cloud’s name it means precipitation might fall

AltitudeAltitude Names HIGH – 6,000 meters + MEDIUM – 6,000 meters to 2,000 meters LOW – Below 2,000 meters Make-up / Other MULTI-LEVEL Draw this in

Primarily composed of ice crystals and include the following: HIGH altitude clouds – 6000 meters + 1.Cirrus clouds

2. Cirrocumulus clouds

3. Cirrostratus clouds They “blanket” the sky and are usually translucent

They can contain ice crystals and/or water droplets and may occasionally be associated with some light precipitation. Alto means MID MEDIUM altitude clouds – 2000 meters to below 6000 meters 4. Altocumulus They appear “puffier” than the HIGH level cirrocumulus because we’re closer to them!

5. Altostratus

6. Cumulus Low clouds are most often composed of water droplets, but can have ice crystals in colder climates. LOW altitude clouds – Below 2000 meters Cumulus clouds tend to be “opaque” due to their “thickness”

7. Stratocumulus

8. Stratus People often refer to a Stratus cloud filled sky as “overcast”

FOG is considered a low Stratus cloud that is in contact with the ground So... Fog = Stratus Cloud NOT a separate cloud type!

9. N i m b o s t r a t u s These clouds are very dark, usually overcast, and are associated with large areas of continuous precipitation A gray and rainy day is usually filled with Nimbostratus clouds! Multi-layer clouds:

10. CUMULONIMBUS These are the clouds that can produce lightning, thunder, heavy rains, hail, strong winds, and tornadoes. They usually have large anvil-shaped tops Can extend above 60,000 feet

All together

Special Clouds: Mammatus Clouds

Here are some other, rarer, types of clouds:

Produced by the flow of air interacting with mountainous terrain. Orographic clouds CAP cloud

Lenticular cloud Lens-shaped clouds that can result from strong wind flow over rugged terrain

SUNDOG

These clouds are called Undulatus Asperatus. They are very rare

The clouds actually dissipate before storms form, despite their dark and threatening appearance. This could be the first new cloud formation to be added in over 50 years.

Taken in Gilberts, Il. by Caitlin Gurgone March 16, 2012

Garrett Schneider’s Fire Rainbow pictures 2013

Determining Cloud Level Low-level cumulus clouds are about the same size, or larger than, your fist. Mid-level cumulus clouds are farther away and the individual cloud pieces are about the size of your thumb. High-level cumulus clouds are smaller still, with individual cloud pieces about the size of the nail on your little finger. To determine cumulus cloud level hold your hand out at arm’s length and compare the size of the cloud “part” to the following:

Stratus clouds have no distinct cloud pieces to measure and a general rule is that cloud opacity tends to decrease with height. Thus, by observing how much the cloud obscures the Sun, you can estimate the level of a stratus cloud. Low-level clouds are generally thicker than mid-level clouds, and a high-level cirrostratus is very thin. If there is precipitation, the chances are very good that you are dealing with a low-level cloud. Mid-level clouds occasionally precipitate, but this is a rare occurrence.

The END!