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Resource Section
for Meteorology
| Temperature
| Clouds | Precipitation | Wind |
Atmospheric Pressure |
|Humidity&Dew point |
Forecasting | Hurricanes /
Typhoons / Cyclone|
|Snowstorms | Thunderstorms |
Tornadoes | Global Issues |
Glossary |
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Clouds |
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High Level Clouds
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Mid Level Clouds |
Low Level Clouds |
Convective Clouds | Hurricanes and Tornadoes |
Other Types Of Clouds | How Clouds Form
| Credits |
Clouds, we see them almost everyday.
To observe them, to identify them, all you need is your eyes. A cloud is
comprised of visible ice crystals and /or water droplets suspended in air. Clouds can be big or little , thick or thin, existing in a seemingly endless
array of shapes and sizes. The purpose of this module is to introduce how
clouds develop and their different classifications, so that with a little
practice, you too can become reasonably accurate in identifying them .
Cloud Chart
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Convective Clouds
Probably the most familiar
of the classifications is the Cumulus cloud , and the variety of shapes, sizes and colors it is able to attain. Generated most commonly through
either thermal convection of frontal lifting, what may begin the day as
harmless -looking cumulus clouds, exits the potential for tremendous
vertical development come afternoon. Sometimes to a height in excess of
39,000ft (12,000m), releasing incredible amounts of energy by the
condensation of water vapor within the cloud itself.
For Further insight into the
different types of cumulus clouds, choose from the following list
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Fair weather cumulus have the appearance of floating cotton and
have a lifetime of 5-40 minutes. Known for their flat bases and distinct
outlines, fair weather cumulus exhibit only slight vertical growth, with
the cloud tops designating the limit of the rising air. Given suitable
conditions, however, harmless fair weather cumulus can later develop
into towering
cumulonimbus clouds associated with powerful thunderstorms.
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A principal cloud type
(cloud genus) of vertical development. Exceptionally dense and
vertically developed clouds, occurring either as isolated clouds or as a
line or wall of clouds with separated upper portions. These clouds
appear as mountains or huge towers, at least a part of the upper
portions of which are usually smooth, fibrous, or striated, and almost
flattened. This part often spreads out in the form of anvil (incus) or
vast plume. Under the base of cumulonimbus, which is very dark, there
frequently exists virga, precipitation, and low, ragged clouds, either
merged with it or not. Its precipitation is often heavy and always of a
showery nature. |
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Other
Cloud Types
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 Contrail A contrail ,also known as a
condensation trail, is a cirrus -like trail of condensed vapor that is
produced by jet aircraft flying at high altitudes .
Contrails |
Kelvin-Helmholtz
Wave-like clouds that form as a result of a strong change
in wind speed across two adjacent layers of air .
Kelvin-Helmholtz
Clouds |
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Mammatus
clouds
Named after their "pouch- like " appearance,
Mammatus are most commonly seen on the underside of
cumulonimbus clouds ,though they have been observed to be associated with
other cloud types as well .
Mammatus
Clouds
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| Orographic Clouds The forced lifting of air by topographical features, for
example mountains, produces a special classification of clouds known as
orographic clouds .
 Orographic
Clouds
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| Pileus Clouds A smooth cloud that is found above or attached to either
the top of a topographical feature ,such as a mountain , or a growing
cumulus tower .
 Pileus
Clouds
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Hurricanes and Tornadoes
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How Clouds Form ?
| We know
that clouds form when rising air cools and the moisture in it condenses
to form water droplets. But do you know what makes the air rise in the
first place? Let me tell you. |
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Air rises for three main reasons: |
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Sunshine
– heat from the sun or warm ground
warms the air and makes it lighter. It therefore rises into the sky.
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The terrain – air may rise as it is forced
upwards due to changes in the terrain (landscape). This often occurs
when wind blows air either over mountains, or over cliffs onto land
from the sea.
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A front
– air can also rise at a weather
front. At cold fronts, cold air is pushed under warm air, forcing it
upwards and at a warm front, warm moist air is forced up and over the
cold air.
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In all three of these cases, the warm moist
air will cool as it rises, and so the moisture it contains will condense
into water droplets – forming clouds. |
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Created by Niru Khanna
Click here to view my
portfolio.
Last update on 10-03--06
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