The Term precipitation denotes all the form of water that reaches earth through the atmosphere. The term Precipitation includes different forms of water, it can be in the form of snow fall, rainfall, hail, frost and dew.
Requirements of Precipitation:
- For Precipitation to form, the atmosphere must have moisture.
- Sufficient nucleii should be present so that condensation may take place. The nucleii are usually salt particles and are available in plenty.
- Weather conditions must be good so that condensation of water vapor to take place.
- When condensation takes place, the product of condensation reaches the earth, then precipitation will form.
- Precipitation results when small droplets of water come together and coagulate to form larger drops that can drop down to earth.
Engineering Hydrology by k Subramanaya.