Clouds

Without water in the air there would be no clouds or precipitation. A CLOUD is a mass of billions of tiny droplets of water or crystals of ice floating over the earth. When warm water evaporates, the warm air and water vapor rise into the cooler upper air. Then the water vapor collides with tiny, cold dust particles in the air and condense into minute droplets. Billions of these droplets together form a cloud.

 

Clouds form when warm, moist air meets cold air.

 

 

Small patches of clouds grow quickly into large heaps of clouds. Full-size clouds only last an hour or two while the air that rose is still warm. When there is no longer any heat in the air, the clouds fade away and are replaced by new clouds.

Clouds can be made of water droplets or ice crystals that are so small that the slightest air movement will support them and keep them from falling to the ground. The tiny cloud droplets are so small, in fact, that it takes about one million of them to make a single raindrop and many of them evaporate before they fall to the ground. It is only when the little droplets repetitively collide and COALESCE to combine into much larger drops that they become too heavy for the cloud to hold and they fall as rain.

Scientists believe that even summer rain begins as ice crystals that melt as they pass through warmer air. In winter, the ice crystals grow into snowflakes as they fall through the frigid air.

Hail is formed when small ice balls fall toward the earth and are carried back to the cloud by the air currents. Each time the ice ball returns to the cloud, a new layer of water is added. This water freezes and becomes ice. Again and again the iceboat is returned to the cloud, getting larger each time, until finally it is so heavy that the air can not push it back up into the cloud, and it falls to earth as hail.

 

 

Clouds are classified by shape and color. The international system created in the 1800's used three basic categories for classifying clouds: CUMULUS, STRATUS, and CIRRUS. There are subdivisions in these categories, however, and today we have ten clouds in the modern classification system.

CUMULUS: puffy, white clouds that are often flat on bottom and dome-shaped on top. about a mile above earth. fair weather clouds

CCUMULUS

CUMULUS

CUMULUS

CUMULUS

 

STRATUS: flat layers or blankets of gray clouds which often carry drizzle or steady rain. about 2,000 feet above the ground. stratus clouds at ground level are called fog.

STRATOCUMULUS

STRATOCUMULUS

STRATUS

 

CIRRUS: feathery wisps and curls made of ice crystals. They are high above the earth.

CIRRUS

CIRRUS

 

 

NIMBOSTRATUS: dark gray clouds that produce hours of rain or snow. They start near the ground but can extend high into the sky.

ALTOSTRATUS: Neither high nor low, these clouds form a layer made of water droplets

CIRROSTRATUS: made of ice crystals. They occur very high in the sly.

CUMULONIMBUS: billow upwards eight to ten miles and are flat and dark on the bottom. They are storm clouds called "THUNDERHEADS", and are often associated with rain, thunder, lightning and tornados.

ALTOCUMULUS: medium-elevation clouds that look like flattened cumulus clouds almost joined together.

CIRROCUMULUS: produce a sky that looks like fish scales. The clouds appear as rows of tiny ice clouds.

STRATOCUMULUS: occur when cumulus clouds spread into layers. Long rolls of stratocumulus clouds indicate the coming of fair weather.

 

 

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