Weather for Secondary 1

1. WEATHER
7.1 Layers of the Earth’s Atmosphere
7.2 Factors of Weather
7.3 Monsoons
7.4 Tropical Whirldwinds
7.5 Clouds
7.6 El Nio and La Nia
7.7 How to Avoid Danger during Severe
Weather
7.8 STEM Activity
7.9 Review Questions

2. Vocabulary Words:
• 1. Weather
• 2. Humidity
• 3. Pressure
• 4. Atmosphere
• 5. Ozone
• 6. Gravity
• 7. ultraviolet rays
• 8. Breathe
• 9. Meteorology
• 10. Troposphere

3. The Atmosphere
• The air that surrounds our
Earth is called the atmosphere
• It is made up of mixture of
gases and consists of different
layers.
• It provides shelter for the Earth
• It consists of 5 layers

4. Layers of the Earth’s Atmosphere

5. 1. Troposphere
• The lowest layer
• All living things on land
live in this layer.
• It is about 10 km high
• It contains 75% of the
atmospheric gases
• Our weather occurs in
here.

6. Composition of Earth’s
Atmosphere

7. 2. Stratosphere
• It is located between 10
km and 50 km above the
Earth’s sea level.
• There are no clouds and
no winds in this layer.
• Most planes fly in this part.
• It contains a thin layer of
ozone, O3.
• Jets fly in here because it’s
calm.

8. Ozone (O3)
Ozone Layer
It is important to protect us and other living things from dangerous
Ultraviolet rays from the sun.

9. Ozone Hole by Year

10. 3. Mesosphere
• The layer above the stratosphere which
extends up to a height of 80 km.
• When meteors fall down on Earth, they slow
down and mostly burn in this layer.
• This layer does not absorb energy from the
sun, so it starts to cool.

11. Met eor s bur n i n
t he Mesospher e

12. 4. Thermosphere
• It is found
between 80
km to 700 km
above Earth’s
ground.
• Space shuttles
fly in here.
• Aurora lights
can be
observed.
Aurora Lights

13. Space Shuttles
in Thermosphere

14. 5. Exosphere
• It is the outer layer of the atmosphere.
• Satellites circulate around this area.

15. Borders between layers:
• Tropopause
• Stratopause
• Mesopause
• Thermopause

16. Temperature in different
layers of atmosphere

17. Weather
Meteorology
- a branch in Science which
studies about the Weather.
Weather- it is defined as the
present state of the atmosphere.
( warm/cold, rainy/sunny, windy)

18. Factors Affecting Weather
1. Air Humidity
2. Air Pressure
3. Air Temperature

19. 1. Air Humidity

20. Humidity
• is the amount of water vapor
present in the air.
• Water vapor is the gaseous state of
water and is invisible to the human
eye.
• Humidity indicates the likelihood of
precipitation, dew, or fog.
* Hydrometer- is the instrument used
to measure humidity.

21. Today: Nov. 15, 2017

22. 2. Air Pressure
• Also called atmospheric
pressure.
• Defined as the weight of air
above a given point per surface
area.
• At higher altitude, the fewer
molecules, the lower pressure
acts.

23. Air Pressure
• Barometer
- the instrument that measures
atmospheric pressure
AT sea level, the pressure of 760
mmHg and it decreases as you
go high altitude.

25. Air Temperature
• It is the most important factor that
influences our weather.

26. Reporting Next Week
• Group 1 (Monsoons)
• Group 2 ( Tropical Whirlwinds)
• Group 3 (Clouds)
• Group 4 ( How to Avoid Danger
during Severe Weather)
• Group 5 (El Nio and La Nia)
All groups should prepare 5
questions for quiz.

27. Monsoons
• Occur only in India and
Southeast Asia.
• Monsoon winds are northeast
winds that appear in the winter
and southwest winds that appear
in the summer.

28. * Monsoons are large-scale sea breezes which occur when
the temperature on land is significantly warmer or cooler
than the temperature of the ocean.
•These temperature imbalances happen because oceans
and land absorb heat in different ways.
•Over oceans, the air temperature remains relatively stable
for two reasons:
1. water has a relatively high and because both
conduction and convection will equilibrate a hot or cold
surface with deeper water (up to 50 meters).
2. dirt, sand, and rocks have lower heat capacities
and they can only transmit heat into the earth by
conduction and not by convection. Therefore, bodies of
water stay at a more even temperature (stable), while land
temperature are more variable (not so stable).

29. Monsoon clouds

30. Tropical Whirlwinds
These are low pressure systems
that form over tropical regions over
the oceans.

31. Clouds
• Are collections of tiny droplets of
water suspends in the air.
Groups:
1.Stratus
2.Cumulus
3.Cirrus

33. The Making of a Cloud
http://www.pbs.org/wgbh/nova/labs/lab/cloud/research/intro/

34. El Nino and La Nina
• Are natural part of the global
climate change.
• Occurs in the Pacific Ocean and
the atmosphere above it changes
from normal state for several
seasons.

35. El Nino
• Warmer than average
temperatures over western and
central Canada, and over the
western and northern US.

36. La Nina
• Cooler than normal sea surface
temperatures in the central and
eastern Pacific Ocean.
Effects:
1.Changes in patterns of rainfall
and temperatures
2.Drought (El Nino)
3.Flooding (La Nina)

37. How to avoid Danger
in Severe Weather:
1. Do not go out to open areas
during storms or cyclones.
2. Close all doors and windows in
your building.
3. Stay away from sea, lakes and
other waters, don’t go swimming.
4. Do not drive motorcycles or cars.
(page 156)

38. Seatwork:
Directions:
Answer in your Science notebook
page 160 of Science textbook.