CLOUDS
What is
CLOUD?
A white or gray mass in the sky that is made of many very small drops of water. Clouds are the basis of precipitation. Clouds work as a blanket or shadow of the atmosphere. Clouds are the most important part of the atmosphere and climate system.
Cloud Formation Process
Clouds are created when water vapor turns into liquid water droplets.We call this process ‘evaporation.’ Evaporation is the concept of phase change of water. The liquid state(water) changed into gas state(water vapor). Evaporation happens when water molecules get energy from a heat source.
In the other way, the most important factor of cloud formation is ‘the rise of the air.’ When the air rises, its temperature gets cool. The air temperature reaches the dew-point temperature. The water condenses, and cloud forms.
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There are some factors that the air rises:
CLOUD CLASSIFICATION
In 1802, the first classification of cloud was first appeared by Luke Howard.
The World Meteorological Organization(WMO) extended Luke Howard’s classifications.
Now there are 10 main groups of cloud.
High Clouds (CH)
Clouds usually form above 5,000m.
High clouds are composed in cold tropospheric temperatures, the clouds are mostly of ice crystals and are thin and white.
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Type : Cirrus, Cirrocumulus, Cirrostratus
Medium Clouds (CM)
Clouds usually form between 2,000-7,000m. The bases of medium clouds in the middle level of the troposphere. Medium clouds composed of water droplets, ice crystals, and supercooled droplets.
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Type : Altocumulus, Altostratus, Nimbostratus
Low clouds (CL)
These clouds usually form below 2,000m. Low clouds normally consist of liquid water droplets and super-cooled droplets.
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Type : Stratocumulus, Stratus, Cumulus, Cumulonimbus
These are the clouds that will be mentioned in Method / Analysis part.
CLOUD FEEDBACK
1
WHAT IS FEEDBACK?
Feedback is a circular process of influence where action influences on the action again.
If the action affects itself, and the phenomena became larger than the beginning, we call the process as 'positive feedback.'
If not, the action affects itself to make the action smaller than the beginning, we call the process as 'negative feedback.'
2
POSITIVE FEEDBACK
clouds formation ->
clouds’ greenhouse effect -> global warming->
water vapor increases ->
clouds increase
3
NEGATIVE FEEDBACK
clouds formation ->
clouds’ albedo effect ->
the temperature of the Earth decreases ->
water vapor decreases ->
clouds decrease