The Hydrosphere

There are 2 types of water

Salt water (97.21%)

Fresh water (2.79%)

The water cycle

Water is always changing
its form. It goes from solid
to liquid to gas and back
again. This is the water
cycle.

Evaporation of sea water,
plants, ground, rivers and
lakes.

Condensation

Wind

Precipitation

Infiltration

Groundwater

It is in oceans and seas, and covers the 71%
of the Earth's surface. Not all seawater has got the same salinity.

Seawter is constantly moving
because of the currents, tides
and waves.

Tides are the rising
and falling of sea
levels. They are
caused by the
gravitional forces of
the Moon.

Ocean currents are like
big rivers moving within
the ocean. This currents
hasn't got the same
salinity or temperature.

Wavesthe up and down
movement of the surface
of oseans and seas. They
are caused by wind. They
rise and fall in a circular
movement. This domino
effect gives the impression
that waves move towards
the beach.

How we use oceans and seas.

ENERGY SOURCE
Oil and gas are found under the
sea. Scientists are looking for ways
to turn the force of tides and waves
into energy.

TOURISM
The sea and the coast
have become a resource
for tourism. They attract
large numbers of visitors
and create many jobs.

WATERWAYS
Oceans and seas are used as
waterways to transport people
and comercial goods.

DRINKING WATER
Some regions have got places called
desalination plants, wich extract the
minerals and salt from seawater and
turn it into drinking water.

FOOD
Aquaculture is the farming of ocean
plants and animals.

Liquid

Solid

Gas

Groundwater is water
that collects or flows
under the Earth's surface.

Lakes and rivers

Lakes are permanent bodies
of water. The water in lakes
comes from rain, rivers or
groundwater.

Rives are a moving stream
of water. The flow of a river is
the amount of water it carries.

Our atmosphere contains
water in the form of water
vapour. Most is in the
troposphere.

Icebergs and glaciers are
fresh water in solid state
(frozen). It inclodes all the
ice in the world and most of
it is in the polar icecaps. The
rest is in mountains.

HOW DO WE USE FRESH WATER

WATER AND AGRICULTURE
Agriculture is the activity that
uses most water. (Spain 80%)

DIGGING FOR WATER
Groundwater in aquifers
is an important freshwater
reserve. Many communities
depend of this water.

URBAN UNDEGROUND DEPOSITS
Cities build facilities underground to
collect rainwater and use it for cleaning
and irrigation servicies.

LEISURE AND WATER
Places with snow, rivers
and lakes attract tourism.

POSITIVE EFFECTS OF
RESERVOIRS
Water form rivers is sometimes
stored in reservoirs. Many dams
are used to produce energy in
hydroelectric plants.

Oceans

Pacific ocean

Atlantic ocean

Indian ocean

Antartic ocean

Artic ocean