refers to all weather conditions for a given location over a period of
time. The term weather refers to the state of the atmosphere over short
periods of time. Weather
can change from hour to hour, from clay to day, from month to month, or
even from year to year. For periods of 30 years or more, however, meteorological
records reveal that distinct weather conditions prevail over different
parts of the world. Each set of conditions forms a climate type, and the
area covered by a particular type is called a climate region.
when air cools below its dew point. The dew point is the temperature at
which air becomes saturated, or filled, with moisture. Although clouds
can differ greatly in size, shape, and color, they all consist of visible
masses of tiny water droplets or ice crystals, because its capacity to
hold water is limited, very much like a sponge. (photo from Nat.
Geogr. Soc.). Warm air can hold more water vapor than cold air can, and
lowering the temperature of a mass of air is like squeezing a sponge, moist
air becomes cloudy with only slight cooling, whereas dry air must be cooled
more to form clouds.
CREDIT: Study the pictures of the clouds shown here.
Classify the clouds and send you result to Prof. Longoria in a separate
A Classification of Clouds
classification of clouds originally proposed by Luke Howard, there are
three main types of clouds: cirrus,
Cirrocumulus: A cirriform cloud with vertical development, appearing as a thin sheet of small white puffs which give it a rippled effect. It often creates a "mackerel sky", since the ripples may look like fish scales. Sometimes it is confused with altocumulus, however, it has smaller individual masses and does not cast a shadow on other elements. It is also the least common cloud type, often forming from cirrus or cirrostratus, with which it is associated in the sky.
A cirriform cloud that develops from cirrus spreading out into a thin layer,
creating a flat sheetlike appearance. It can give the sky a slightly milky
or veiled look. When viewed from the surface of the earth, these ice crystals
can create a halo effect around the sun or moon. This cloud is a good precursor
of precipitation, indicating it may occur within 12 to 24 hours.
Stratus clouds are stratified, or layered, often blanketing the entire sky with a uniform cover. Clouds in the stratus group often form at the boundary of a warm front. Warm, moist air is forced up over cold air, producing clouds across the entire front. Stratus clouds form when stable air does not permit cumulus ones to develop. They often blanket the sky as a gray layer stretching from horizon to horizon and can measure hundreds of kilometers in length and width. If precipitation falls from these clouds at all, it is usually in the form of drizzle or light snow. <move up>
Cumulus clouds are lumpy or heaped. The weather they bring depends on their height and size. Puffy cumulus clouds form when thermals, up drafts of warm air, cool as they rise to altitudes of about 1 kilometer (3,300 ft), The higher the clouds are, the drier the atmosphere and the fairer the weather will be. <move up>
denotes clouds whose bases are between 2 and 6 kilometers (6,500-20,000
ft) above the earth, such as altocumulus
clouds. <move up>
produce rain take the prefix nimbo-
or the suffix -nimbus,
as in nimbostratus
or cumulonimbus. Nimbostratus
clouds bring continuous precipitation that can last for many hours.
Cloud Seeding - any technique carried out to introduce artificial substances into the cloud with the intent of altering the natural development of that cloud. <move up>
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