What is Precipitation
Precipitation is a natural process by which the Atmospheric Moisture falls on the surface of the earth in various forms such as rain, sleet, and hail.
- If Precipitation involves drops of water, it is called rainfall.
- If it involves snowflakes,It is called snowfall.
- Sometimes a thin layer of ice is formed on the ground due to the freezing of raindrops and flakes or snow,It is called sleet.
- Sometimes raindrops merge and freeze and fall on the ground on stones of ice.It’s called Hail Stones.
Types of Rainfall:
- In the tropical region, the overlying layers of air are heated up through conduction and the hot air expands and becomes lighter.
- The Lighter air rises up.
- When it reaches so high , where the temperature is below its dew point,condensation takes place.
- Then a heavy rainfall or hail storm will occur.
- This type of rainfall which is associated with thunder and lightning is called Convectional type of rainfall.
- Due to the differential heating and cooling of the land masses and water bodies and also due to the prevailing planetary winds,air flows from the oceans and seas onto the land surface.
- When a hill or mountain obstructs the path of such moisture -laden winds, the wind rises up and gives heavy rainfall on the wind -ward side of the barrier.
- There would be no rainfall on the other side of it, such regions are called Rain-shadow Regions.
3.Cyclonic Rainfall: Cyclonic Rainfall is associated with the passage of a cyclone or a depression.There are two types of cyclones
- The Tropical Cyclones
Winds from the surrounding high-pressure areas below toward the centre of the low pressure in a circular motion from all around and lifted up.The Uplifted air gives heavy rainfall.
2. The Temperature Cyclones
In the temperature Zone, cyclones occur when the cold air masses converge with the warm Air Masses and The warmer air,being lighter is lifted up by the denser cold air and it results in the rainfall.
Also, read Atmospheric Pressure and its Factors