2. WHAT IS WATER CYCLE
The cycle of processes by which water
circulates between the earths oceans,
atmosphere and land involving
precipitation as rain and snow, drainage in
streams and rivers, and return to the
atmosphere by evaporation and
transpiration.
3. STAGES OF WATER CYCLE
•Evaporation
•Transpiration
•Condensation
•Precipitation
•Infiltration
•Surface runoff
4. EVAPORATION
One of the major process in the cycle, is the
transfer of water from the surface of the earth
to the atmosphere. By evaporation water in the
liquid state is transferred to the gaseous or
vapour state. The main factors affecting
evaporation are temperature, humidity, wind
speed and solar radiation. The principle source
of water vapour is the oceans but evaporation
also occurs in soils, snow, ice.
5. TRANSPIRATION
Transpiration is the process by which moisture
is carried through plants from roots to small
pores on the underside of leaves, where it
changes to vapors and is released to the
atmosphere Transpiration is essentially
evaporation of water from plant leaves.
Transpiration rates vary widely depending on
weather conditions, such as temperature,
humidity, sunlight, soil type, wind, land scope
and type of plant.
6. CONDENSATION
Condensation is the process by which water
vapor in the air is changed into liquid water.
Condensation is crucial to the water cycle
because it is responsible for the formation of
clouds. Clouds form when water vapor
condenses around small particles like bits of
dust or smoke in the air. Depending on the size
of the drops, these particles may or may not be
visible.
7. PRECIPITATION
Precipitation is water released from clouds
in the form of rain, freezing rain, snow or
hail. It is the primary connection in the
water cycle that provides for the delivery of
atmospheric water to the earth. Most
precipitation falls as rain. Precipitation
forms in the clouds when water vapor
condenses into bigger and bigger droplets of
water. When the drops are heavy enough,
they fall to the earth. If a cloud is colder,
like it would be at higher altitude the water
droplets may freeze to form ice.
8. INFILTRATION
Infiltration is a part of the water cycle and
occurs when water moves into the ground
from the surface and begins to soak into
the soil and rock layers under earth. The
water can make its way to the surface from
the earth by rain, snow melting or in
human activity such as watering.
9. SURFACE RUNOFF
Runoff includes not only the waters that travel
over the land surface and through channels to
reach a stream but also interflow, the water
that infiltrates the soil surface and travels by
means of gravity towards a stream channels
and eventually empties into the channel.
10. IMPPORTANCE OF WATER CYCLE
• The water cycle is important to all life on earth for many reasons. All living
organisms required water and the water cycle describes the process of how
water moves through the plants. Plants wouldn’t grow without precipitation.
Glaciers, ice and snow can act as stores of fresh water for both human and
other organisms. All of these process sustain life and create the ecosystems
around us. If water didn’t naturally recycle itself, we would run out of clean
water, which is essential to life.
• It is also involved in maintaining aquatic ecosystem.
• Greatest natural process which plays a significant role by a continuous
movement of water on above and below the surface of earth.
