Cloud formation and precipitation processes

 Cloud formation & Precipitation

Cloud formation

    Condensation of water above the Earth surface creates clouds. In general cloud develop in any air mass that becomes saturated (relative humidity become 100%).

    Saturation can occur by way of atmospheric mechanism that causes the temperature of an air to be cooled to its dew point. 

The following processes can be responsible for the formation of the clouds.

    When air is forced to rise because of the physical presence of elevated land. As the parcel of air rises, it cools due to adiabatic expansion at a rate of approximately 10° C / km. 

    The development of clouds and resulting heavy quantities of precipitation along SW coast of India, during the SW Monsoon, is due to these processes.

    A rain shadow is a patch of land that has been forced to become a desert because mountain ranges blocked all plant-growing, rainy weather. On one side of the mountain, wet weather systems drop rain and snow. On the other side of the mountain, the rain shadow side, all that precipitation is blocked.

Precipitation

    The word precipitation is derived from a Latin word, ‘Precipitatio’ meaning headlong falling down. It include rain, snow, hail, sleet & Fog. These forms depend upon the following conditions. 

• The temperature at which condensation takes place
• The condition encounters as the parcels passes through the air. 
• The type of clouds and their heights from the ground
• The processes generating phenomena

Forms of precipitation:

    Precipitation results from the continued condensation and growth of the moisture parcels until they become too large to remain suspended in the air.

• If the condensation occurs above 0°C, the resulting precipitation in the form of rain
• If the rain passes through a layer of colder air on the way down it may freeze and fall as sleet 
• In strong turbulent current of thunderstorm, water droplet may carried upward in to freezing temperature and eventually fall as hail
• Snow is not a frozen rain, but forms when moisture crystallizes directly from vapor at a temperature below freezing.
• Ice storm results when rain already near the freezing point, falls on the colder ground and vegetation and freezes upon contact.

 If found interesting check the video below for more

Reference:

1. Atmosphere, Ocean, and Climate Dynamics - An Introductory Text (John Marshall & R. Alan Plumb).

2. Climatology – second edition – (John E Oliver, John J Hidore)

3. Atmospheric Thermodynamics - John M. Wallace, Peter V. Hobbs.