1. What is
weather?

2. Weather
• Weather it is the condition of the atmosphere
at a particular time and place .

3. What can cause the changes of
weather?
• Weather variables:
1) Temperature
2) Wind
3)Moisture
4)Precipitation

4. How to predict weather ?
1)Weather Balloons
2) Weather satellites

5. • 3)Doppler radar
It IIt can detect :1)Precipitation
2)Wind direction
3) Wind speed

6. Insolation
• It is the amount of sun energy reaching the
Earth at a given time and place

7. What is the angle of insolation?
• a measure of how high the sun is in the sky
• measured from the horizon up to the position of
the sun

8. What happens as the angle increases or
decreases?
• As the angle of insolation increases, intensity
increases. (heat concentrated in smaller area.)

9. • As the angle of intensity decreases, heat is
spread out over a larger area.

10. Low angle: Less absorbed
High angle: More absorbed
Earth
• Intensity of insolation varies over the Earth because
of the curvature of the Earth.

11. Where is intensity the greatest and
lowest?
• Intensity greatest near
the Equator.
– Sun’s rays are direct
• Intensity low at the
poles

12. At what time is the angle and
intensity of insolation greatest?
•The noon sun has the greatest angle of insolation.

13. How to measure angle of insolation ?
• WE can measure ion angle of insolation

14. Why does the angle of insolation
change between midday and
evening?
The angle of insolation decreases because the
Earth’s rotation ,and the air temperature usually
decrease

15. Measuring Temperature

16. Pressure
• It is the weight of air pressing on a unit area.

17. • The difference of air pressure is due to
unequal heating of the Earth.
• Warm air masses have fewer air molecules
than cold air masses.

18. What is the relation between
temperature and pressure ?
As the temperature increases the air particles
are far away from each other decreasing the
pressure
As the temperature increases the pressure
decreases

19. Air Pressure
• Air Pressure is a
measure of the force
of the air pressing
down on the earth’s
surface

20. Air Pressure can vary at any particular
point on the Earth depending on the
density of the air
Density = mass / volume

21. Title: Activity 2. Stop the Leak
Challenge:
Solution:
Results and
Explanation:
Summary:
Date: Feb. 2010
How can you stop the leak in this soda can?

22. Convection Cell
-Suppose air in an area is cool and under high pressure
-If a near by place is warmer and at a lower pressure
-The air will move from high pressure area to a low
pressure area .
This is called “Surface wind”

23. • What do you think can increase the intensity of the wind ?
• As the difference in pressure increases the wind intensity
increases
• Unequal heating and cooling of air results in difference in
pressure
• Where warm air will move
• Up and cold air moves down making a circular pattern of
rising and sinking air and wind called “Convection cell”

24. Sea Breeze

25. Land Breeze

26. Instruments used to measure
”Wind and Pressure”
1)Anemometer
A device used to measure wind speed .
The cups spin faster as the wind blow faster

27. 2)Weather Vane
It is used to measure wind direction . It ‘s a
movable arrow that points in the direction
the wind blowing .

28. 3)Barometer
Measures surrounding air pressure against standard
air pressure