1º ESO BILINGUAL HISTORY. SANTILLANA CLASS BOOK

1. Unit 3
WATER

2. 1- Where is water found?
- On Earth: 71% of the Earth’s surface is covered by
water (salt water is 97%, fresh water just 3%).

4. Activities
Exercises 1 and 2 on page 25.

5. 2- What are rivers?
-River source
-Tributaries
-Basin
-Flow (depends
on the season)

6. The importance of rivers
-Transport
-Water supply: Canals, reservoirs
-Electricity: dams, power stations

7. Activities
Exercise 1 on page 26

8. 3- What are oceans and seas?
They hold almost all the world’s liquid water,
that is salt water.
Salinity is different depending on if the sea is
warmer or colder.
Warm = + salt
Cold = - salt

10. The importance of oceans and seas
-Food
-Raw materials
-Energy
-Tourism
-Transport

11. 4- What are currents, tides and waves?
Map of ocean currents

12. Ocean currents

13. Tides

14. Waves

15. Activities
Exercise 1 on page 28.

16. 5- What are lakes?
Different terms:
-Lake
-Lagoon (small)
-Inland sea (salt water)
Different origins:
-Precipitation
-Rivers or groundwater
-Glaciers

17. Activities
Exercise 1 on page 29.

18. 6- Where are groundwater and glaciers found?
GROUNDWATER. Aquifers.

19. Hot and cold springs

20. The importance of groundwater
-Drinking water
-Source for rivers and lakes
-To grow plants

22. Glaciers

23. Icebergs

24. Homework
Activity 1 on page 30.

25. 7- What problems are related to water today?
WATER CONSUMPTION AND DISTRIBUTION
-3% Fresh water -> 0,014% available
-Increase in population -> increase in
consumption
-Bad distribution
-Consequences: droughts or floods

27. Water pollution
and acid rain

29. Activities
Exercises 1 and 3 on page 31.

30. Work at home
Exercises 1, 4 and 5 on pages 32-33.