Clouds Formation

2. WHAT IS CLOUD?

3. • A cloud is a visible mass of tiny particles of water or
ice, or a mixture of both, suspended in the air.
Cloud particles are about 5 to 75 micrometers
(0.0005 to 0.008 cm/0.0002 to 0.003 in) in size,
which explains why light, vertical currents can
sustain them in the air.

4. • Clouds are created when water vapor, an invisible
gas, turns into liquid water droplets. These water
droplets form on tiny particles, like dust, that are
floating in the air.

5. • Types of clouds
• Luke Howard's Classification: (1803)
• Luke Howard has been called the Father of Meteorology. He was the first man to classify clouds. World
Meteorological Organization (WMO) has extended Luke Howard's classification to make to main groups
of clouds.
• High level clouds
• Cirrus
• Cirrocumulus
• Cirrostratus.
• Mild Level Clouds
• Altocumulus
• Altostratus
• Nimbostratus.
• Low Level Clouds
• Stratocumulus
• Cumulonimbus
• Stratus
• Cumulus

6. • Names for clouds:
• The names for clouds are usually combinations of the following prefixes or
suffixes:
• Stratus/Strato = Flat or layered and smooth.
• Cumulus/Cumulo = Heaped up or puffy, like cauliflower.
• Cirrus/ Cirro = High up or wispy.
• Alto Medium level.
• Nimbus/Nimbo = Rain-bearing cloud.
• Types of clouds
• 1- High Level Clouds:
• Above 20,000 feet, composed of ice crystals, thin and white in appearance.
• 2- Mild Level Clouds:
• Between 6000-20,000 feet, composed of water droplets, grey to pale blue in
appearance.

7. • Types of clouds
• 3- Low Level Clouds:
• Below 6,000 feet, composed of water droplets, may contain ice
crystals, light grey in appearance.
• The water cycle
• The Water Cycle consists of 4 main processes:
• 1- Evaporation:
• High temperature cause evaporation of water from water bodies,
i.e. Oceans, Rivers, Lakes etc.
• 2- Transpiration:
• Transpiration, loss of water from plants, enters water into the the
atmosphere.

8. • The water cycle
• 3- Condensation:
• The air and water droplets condense and clouds are
formed.
• 4- Precipitation:
• The clouds looses their water in the form of rain,
hail, snow. This is how water is returned back to
ground and cycle continues.

9. • Cloud formation
• Process:
• Cloud formation occurs through convection. As the intensity of solar radiation
increases, the warmer air becomes lighter and moves upward. As this happens,
the temperature decreases, so does the amount of water vapors air can hold.
Due to this, the process of condensation starts. These vapors rapidly condense
and soon clouds composed of countless billions of tiny water droplets or ice
crystals - result. Clouds are occasionally produced by a reduction of pressure
aloft or by the mixing of warmer and cooler air currents.
• Cloud formation
• Clouds are formed at different heights.
• The characteristics of clouds are formed by the elements available, including the
amount of water vapors, the temperature at that height, the wind, and the
interplay of other air masses.

10. • Factors influencing Cloud Formati
• Factors which influence cloud formation are:
• Surface heating.
• Topography forcing.
• Frontal.
• Convergence.
• Turbulence.

11. • Factors influencing Cloud Formatio
• Frontal:
• Clouds are formed when a mass of warm air rises up over a mass of cold, dense air over
large areas along fronts.
• Convergence:
• Streams of air flowing from different directions are forced to rise where they flow
together, or converge.
• Turbulence:
• A sudden change in wind speed with height creating turbulent eddies in the air.
• Impact of clouds on Environme
• Clouds cool Earth's atmosphere by absorbing heat emitted from the surface and radiating
it to the space.
• Clouds help redistribute extra heat from the equator toward the poles.
• Clouds indicate what type of atmospheric processes are occurring. For Example, Cumulus
Clouds indicate surface heating and atmospheric turbulence.

12. • Impact of clouds on Environme
• The reflection of sunlight from different kinds of
clouds can cool Earth's atmosphere.
• Clouds are required for precipitation and essential
for hydrological cycle.