m

2. Do you know……..?
 Where can we find water in our planet?
 How is sea water different to water in rivers?
 What is the water cycle?
 Why is important not to waste water?
 Some easy ways to save water?

5. WHERE IS THERE WATER ON EARTH?
 97% of water on Earth is salt water. It is found in
the oceans.
 3% of water on Earth is fresh water. It is found in:
 Ice and snow from glaciars.
 Below the surface: groundwater.
 In the atmosphere.
 On the surface.
 In living beings.

6. PROPERTIES OF WATER
 The water molecule is made up of three atoms: H2O
 Water:
 Has no colour, no taste and no smell.
 Is a poweful solvent.
 Absorbs heat: so, water moderates the Earth’s climate by
absorbing heat in summer and emitting heat in winter.
 Freezes at 0 ºC.
 Has cohesion and adhesion.

7.  Cohesion
 Adhesion

8. SEA WATER
 Sea water is salty.
 It contains dissolved gasses: these gasses are
dissolved in the water by two process:
 The movement of the waves.
 The aquatic beings.

9.  The temperature varies with depth:
It is highest at the surface.
It is lower in the deepest
zones.

10.  MOVEMENTS PRODUCED IN THE OCEANS:
 Waves: occur on the surface, and they are caused by the
wind. Waves mix water with the air above the surface,
dissolving a lot of oxygen.

11.  Currents: are masses of water which move like rivers
through the sea. They are produced by wind, and
differences in salinity.

12.  Tides: are the periodic rise and fall of the sea level. They
are caused by the gravitational attraction of the Moon
and the Sun.

15. FRESH WATER
 Fresh water is found on the continents.
 It contains much less salt than sea water.
 It is found in different forms:
 Streams: are water courses fed by rain.
 Glaciers: are formed from the accumulation of snow on mountain
tops.
 Rivers: are permanent water courses.
 Lakes: are masses of water contained on depressed areas.
 Groundwater: is water beneath the ground surface.
 Wetlands: are areas where the ground is inundated all year round.

17.  Is the movement of water around, over and through
the Earth. It consist on these processes:
 Evaporation.
 Evapotranspiration.
 Condensation.
 Precipitation.
 Surface Runoff.

18.  Evaporation: liquid water changes to gas. Water
passes from the hydrosphere to the atmosphere.

19.  Evapotranspiration: water evaporates from the
leaves of plants.

20.  Condensation: Water vapour changes to liquid,
forming clouds.

21.  Precipitation: water in the clouds falls to the
ground.

22.  Surface Runoff: surface water moves across the
land, forming rivers and streams.

23.  Infiltration: surface water filters into the
ground, using the pores in the rocks.

26. El Modelado del Relieve por el Agua
http://www.edistribucion.es/anayaeducacion/8420534/U09/U09_01_EPI_04/v
ideo_modelado_paisaje.html
Las Aguas Contaminadas
http://www.edistribucion.es/anayaeducacion/8420534/U09/U09_01_EPI_05/
video_9_5_nb/index.html