The Water Cycle
What really is the Water Cycle?
Do you know that fresh water which you drink is not fresh? It has
been earlier used in one way or the other somewhere in the universe. If
you keep a glass of water in the sunlight, you will realise that some of
it disappears,. Do you know what happens to this water?. When we wash
clothes and put them out to dry, all the water evaporates in the air.
Then this water comes back again to earth in the form of rain. It may
fall on the ground or in a river or into the sea. Do you realise that
all the water in the universe keeps moving in a cycle from pond to air
and then again back as rain , that is why it is called the water -cycle.
Here are five different processes in a water cycle.
When a liquid, in this case water, changes from its liquid state to a
gaseous state due to some heat factors it is called Evaporation. Our
clothes dry when we put it out due to it.
It is the opposite of evaporation. Condensation occurs when a gas
changes into a liquid. This happens when heat is lost. Dew drops are
formed due to this. When water vapour in the air touches grass, which
has become cold due to low night temperature, the water vapour becomes
liquid. Hence we see water drops on the grass in the morning.
It is process where rain water gets infiltrated (soaked) into the
ground. Due to this we get ground water for drinking and irrigation of
Rain is due to this. When atmospheric pressure is appropriate;
temperature in higher skies becomes low, small quantities of water
vapour join together to form big droplets. These big droplets can't bear
their own weight and start falling as raindrops.
The plants absorb water from the soil through their roots, it passes
from the stem and reaches the leaves. Some of this water is lost by the
leaves due to the heat of the atmosphere. This is also a kind of
evaporation, but here water from plants evaporates into the air.