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In this lesson we are going to discuss about the definition of the hydrological cycle and the processes involved

Answer Text:
Hydrological/water Cycle
- Endless interchange of water between the sea, atmosphere and land.

Processes in Which Circulation Is Carried Out
1. Evaporation
- Changing of water into water into water vapour when it’s heated by solar radiation.
Evapotranspiration: Combined loss of water from the soil through direct evaporation and transpiration by plants.
2. Cooling
- Reduction of water vapour temperature as it rises into the atmosphere when it expands due to reduced temperature and pressure.
3. Condensation
- Turning of water vapour into tiny water droplets which form clouds when cooling continues below dew point.
4. Precipitation
-The process in which the earth receives moisture from the atmosphere.
It occurs when droplets formed by condensation combine forming heavier drops which fall on the ground
as rain or may become frozen to form snow, hail, sleet, etc.
5. Surface runoff
- Some of the water from precipitation that flows on the surface into valleys, ponds, lakes, etc.
6. Infiltration
- Entry of water into the ground through pores, joints and cracks in rocks.
7. Percolation
- Downwards and sideways movement of water that has entered into the ground.
8. Overland flow
Surface runoff makes the overland flow.
River water flows back to the oceans where evaporation takes place again and water cycle is repeated.