Climate
Learn about the Factors that are having most influence on climate. At the Equator, the Sun is high in the sky and the climate is hot. In parts of Siberia, far inland, the annual temperature range is m
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Clouds that are formed above 20 thousand feet are the High-level clouds. At such height the temperature is so cold that, these clouds are composed of ice crystals. These types of clouds are typically white and thin in appearance, but can appear in a magnificent array of colors when the sun is low on the horizon.
Clouds
Cloud is masses of water droplets or ice crystals suspended in the air. When air rises, it expands and cools. Cool air cannot hold as much water vapor as warm air. Eventually the rising air cools to a temperature at which it can no longer hold all of its moisture in the form of vapor. The extra water vapor is deposited on small particles that are always to be found floating in the air i.e. salt crystals, pollen, dust, etc. and it forms the water droplets or ice crystals that make up a cloud.
Clouds have two distinct forms. Cumu-liform (heap) clouds usually have a fairly level base with fluffy upper parts. Stratiform (layer) clouds usually appear in an even, unbroken blanket across the sky. Cloud forms are important in weather forecasting. The ten main cloud types are described below.
TYPES OF CLOUD
Cirrus: Delicate, white, detached, high clouds, with fiber-like appearance. Its many forms include 'mare's tails'.
Cirrocumulus: Thin sheet or patch of high cloud in the form of ripples or rounded small masses, often merged together. Sometimes produces a 'mackerel sky'.
Cirrostratus: Transparent film of fiber-like, whitish high cloud, frequently seen before a depression. It is generally the cause of a halo seen round the Sun or Moon (effects of ice crystals on light).
Altocumulus: Grayish-white sheet or patch of medium-high cloud, with shading, made up of rounded heaps, often merged together.
Altostratus: Grayish sheet of medium-high cloud, either fiber-like or uniform. Often produces the 'watery' sky seen before depressions.
Stratocumulus: Grayish-white sheet of low cloud, with shading, made up of rounded masses, often merged together.
Stratus: Uniform, gray, low cloud layer, similar to fog. May envelop high ground.
Nimbostratus: Gray, often dark, layer of cloud, sometimes blurred by falling rain or snow.
Cumulus: Detached, low cloud heaps, developing upwards, brilliant white when lit by Sun.
Cumulonimbus: The thunder-cloud. Dense, with upper portion usually flattened out in shape of anvil, its low base may be very dark.
