1. THE ATMOSPHERE

2. COMPOSITION OF THE ATMOSPHERE

3. Was the composition of the
atmosphere always the same?
• Was there always oxygen in the
atmosphere?
• Evolución composición atmósfera

5. STRUCTURE OF THE ATMOSPHERE
• There are 5 layers:
– TROPOSPHERE
– STRATOSPHERE
– MESOSPHERE
– TERMOSPHERE
– EXOSPHERE

8. • Sobre las distintas capas
– http://recursostic.educacion.es/secundaria/edad/1e
– Video
• http://www.youtube.com/watch?v=Jv9r7ZCN-DU

9. • Aurora borealis
• Video aurora borealis
• Video troposphere

10. What happens in the..?
• Troposphere
– The closest layer to the Earth
– Meteorological phenomena take place here
– The greenhouse effect
– 80% of the gases are in this layer.
• Stratosphere
– It contains the ozone layer
• Mesosphere
– Falling stars form here

11. • Ionosphere or Termosphere
– Aurora borealis and aurora australis (Northern
and Southern lights) are produced here
• Exosphere
– The last layer
– Very very few air molecules in this layer
– No clear boundary between this layer and space

12. Weather and climate
• Weather:
• is what the forecasters on the TV news
predict each day.

13. Weather conditions include:
•
•
•
•
•
Humidity Amount of water vapour.
Clouds.
Precipitacion (rain, snow or hail)
Temperature (hot or cold air)
Wind

14. Atmospheric pressure
• The pressure air exerts on a surface.
• Where is it higher, at sea level or at the
top of a mountain?

15. Low and high pressure areas

16. Air moves from high pressures
areas to low pressure areas

19. • Climate:
– is the average weather in a place over
many years.
– While the weather can change in just a few
hours, climate takes hundreds, thousands,
even millions of years to change.

20. Factors affecting climate are:
• Latitude. How far North or South a place is
from the equator.
Longitude. The East or west position of a
point on the Earth´s surface.

21. • Video explaining latitude.
– http://www.youtube.com/watch?
v=K2b4iInGYq0
• Longitude video
– http://www.youtube.com/watch?v=3zj6tXcLAk#t=10

22. • Distance from the sea. Coastal areas
have milder weather than inland areas.
• Ocean currents.

24. • Video Ocean currents
– http://www.youtube.com/watch?
v=Hu_Ga0JYFNg

26. Meteorological instruments
• Thermometer:
– measures the air temperature.
• A BAROMETER:
– measures air pressure.
– It tells you whether or not the pressure is rising or
falling.
– A rising barometer means sunny and dry conditions,
while a falling barometer means stormy and wet
conditions.
– An Italian scientist named Torricelli built the first
barometer in 1643.

28. • Anemometer
– measures wind
speed.
Weather vane/ Wind
vane:
– determines the
direction from which
the wind is blowing.

29. • Hygrometer
– measures the water
vapor content of air.
– The humidity.
• Pluviometer
– the amount of rain that
has fallen over a
specific time period.

30. What is atmospheric pressure?
• Video instrumentos meteorológicos
– http://recursostic.educacion.es/secundaria/ed
ad/1esobiologia/1quincena5/1q5_contenidos_
3d.htm
• Animation