*THE WATER CYCLE
*WATER IN OUR WORLD
*WATER UNDER THE
* WATER IN HOUR HOUSES
* WATER FOR PLEASURE
• To know why rainTo know why rain
falls,we have tofalls,we have to
understand the waterunderstand the water
• Water is alwaysWater is always
changing state andchanging state and
place. It moves from theplace. It moves from the
land into theland into the
atmosphere and backatmosphere and back
down again. Thisdown again. This
movement is called themovement is called the
water cycle.water cycle.
1. Water falls from clouds or
rain or snow and collect in
rivers, lakes, seas and
2. The Sun's heat turns some
water into water vapour in
3. The air rises and cools and
some vapour turns back into
a liquid water, forming
•About 97% of the world's
water is salty and is found in
our oceans and seas.
•The other 3% is fresh
water, from ice (in glaciers
and ice sheets), rivers and
lakes, or clouds
WATER IS VERY IMPORTANT IN THE WORLD.WATER IS VERY IMPORTANT IN THE WORLD.
IT IS NECESSARY TO LIVE. A VERY HEALTHYIT IS NECESSARY TO LIVE. A VERY HEALTHY
• WITHOUT WATER WE DESHYDRATEWITHOUT WATER WE DESHYDRATE
OURSELVES. EVERY DAY, THOUSANDS OFOURSELVES. EVERY DAY, THOUSANDS OF
PERSONS DIE FOR HAVING NEITHER FOODPERSONS DIE FOR HAVING NEITHER FOOD
NOR ANYTHING TO DRINK.NOR ANYTHING TO DRINK.
•Almost three-quarters of
Earth's surface is covered
with water, making the
planet look blue from
•Water is essential to life
in earth. Without it, all
animals and plants would
•Oceans and seas make up
most of world's water.
Almost three-quarters of the Earth’sAlmost three-quarters of the Earth’s
surface is covered with water, making thesurface is covered with water, making the
planet look blue from Space. Water isplanet look blue from Space. Water is
essential to live in the Earth.essential to live in the Earth.
• Water is necessary in our lives.Water is necessary in our lives.
• On Earth, 96.5% of the planets water is foundOn Earth, 96.5% of the planets water is found
in seas and oceans, 1.7% in groundwater, 1.7%in seas and oceans, 1.7% in groundwater, 1.7%
in glaciers and the ice caps of Antartica andin glaciers and the ice caps of Antartica and
Greenland, a small fraction in otherlarge waterGreenland, a small fraction in otherlarge water
bodies, and 0.001% in the air as vapour, cloudsbodies, and 0.001% in the air as vapour, clouds
and precipitation.and precipitation.
*Some of the water that falls as rain soaks into*Some of the water that falls as rain soaks into
the ground, slowly trickling down through tinythe ground, slowly trickling down through tiny
air space in soil or through cracks in rocks.air space in soil or through cracks in rocks.
*Eventually the water reaches a layer of rock-*Eventually the water reaches a layer of rock-
called impermeable rock- that will not allowcalled impermeable rock- that will not allow
water to pass through it.water to pass through it.
• The sunThe sun turns water to vapour all the time. Whenturns water to vapour all the time. When
the vapour cools high in the sky it turns intothe vapour cools high in the sky it turns into
millions of tiny drops of water. These makemillions of tiny drops of water. These make
•People in towns and cities use hugePeople in towns and cities use huge
amounts of water every day.amounts of water every day.
•Before the water reaches our taps, itBefore the water reaches our taps, it
passes through treatment works to make itpasses through treatment works to make it
safe to drink. Most used water passessafe to drink. Most used water passes
through sewage works before beingthrough sewage works before being
returned to rives or the sea.returned to rives or the sea.
Water inWater in
our housesour houses
RainRain makesmakes puddles of water on the ground. Thepuddles of water on the ground. The
puddles soon dry up, but the water does not gopuddles soon dry up, but the water does not go
away. It turns into an invisible gas called wateraway. It turns into an invisible gas called water
vapour. The water vapour rises into the air.vapour. The water vapour rises into the air.
Rain can be made eitherRain can be made either fromfrom waterwater
dropletsdroplets in low-level clouds, orin low-level clouds, or fromfrom
melted ice cristals in higher clouds.melted ice cristals in higher clouds.
Very light rain is calledVery light rain is called drizzledrizzle. Sleet is a. Sleet is a
mixture of rain falls through cold airmixture of rain falls through cold air
and partly freezes, or snow fallsand partly freezes, or snow falls
through warm air and partly meltsthrough warm air and partly melts
• Rain does not fallRain does not fall
equally around theequally around the
• People in manyPeople in many
countries do not havecountries do not have
enough water.enough water.
Without taps in theirWithout taps in their
homes, many peoplehomes, many people
have to travel longhave to travel long
distances to find anddistances to find and
carry water.carry water.
Some animals andSome animals and
plats are in dangerplats are in danger
because ofbecause of
chemicals. Wastechemicals. Waste
chemicals fromchemicals from
factories kill plants,factories kill plants,
insects, and fish. Soinsects, and fish. So
do some chemicalsdo some chemicals
used on farms.used on farms.
As for recreation, people canAs for recreation, people can
entertain themselves in almost anyentertain themselves in almost any
sort of body of water: beaches,sort of body of water: beaches,
lakes, water parks and evenlakes, water parks and even
puddles can serve as the basis forpuddles can serve as the basis for
a number of recreational activitiesa number of recreational activities