Explain the water cycle in accordance with the NCERT TEXTBOOK.{3 MARKS}
The water cycle
To understand the water cycle, we should know
- how water is lost from the environment
- the processes of change and the different states of water
- the method by which it is returned to the environment
Water molecules change into water vapour and move into the atmosphere by the process of evaporation. The excess water absorbed by plant roots is released through the pores on the surface of leaves by the process of transpiration.
The process by which water vapour rises up, cools down in the higher atmosphere, and forms clouds is called condensation.
As condensation proceeds, water vapour changes into water droplets. When enough water droplets accumulate, they fall down as rain. This process is called precipitation. The rain replenishes the water in the lakes, ponds, oceans, and other water bodies. The process of rain water thus entering the soil is known as infiltration. When rain water flows over the surface of land before entering the water bodies, it is called surface runoff.
At very low temperatures, water freezes and falls down as hail, snow, or sleet.