1. L.O: SWBAT explain why the angle of insolation (angle of sunlight) gives Earth its climates and seasons.

2. scientists call sunlight: Insolation.
The Earth gets its energy from sunlight.
scientists call sunlight: Insolation.
INSOLATION : INcoming SOLar radiATION

3. Earth’s surface is curved and tilted at 23.50.
Insolation (Sunlight) strikes at different angles on Earth’s curved surface.
Here, the sunlight hits Earth at an angle of 150
Here, the sunlight hits Earth at an angle of 900

4. Areas with a higher angle of insolation have more daylight hours and hotter weather!
The area that gets 900 insolation will have the most daylight & higher temperature.

5. *Angle of insolation: the angle that sunlight hits a place on Earth’s surface.

6. the angle of insolation is why we have:
Seasons
climates
Different lengths of night & day
Different temperatures during morning, noon and night.

7. The angles of insolation can range from 00 to 900.
Rays that strike at 900 are called vertical rays (or direct rays).

8. Very hot & sunny places get an angle of insolation closer to a 900 degree angle.
Very cold places get insolation at much less than 900 degree angle.

9. As the angle of insolation increases, the intensity of sunlight increases.

10. The angle of insolation concentrates the sunlight on an area
The angle of insolation concentrates the sunlight on an area. like a magnifying glass.

11. *the equator has the highest temperatures because it gets the most direct rays of insolation (sunlight)
*the poles have the lowest temperature. they get indirect rays of insolation (the least sunlight)

12. Which location is receiving the highest angle of insolation (sunlight): A, B, C OR D?

13. Which diagram shows the angle of INSOLATION that would produce the greatest intensity of INSOLATION at a location in New York State? A B C D

14. WHICH LOCATION WOULD RECEIVE THE GREATEST AMOUNT OF INSOLATION?

15. WHICH LOCATION GETS THE MOST CONCENTRATED SUNLIGHT? HOW DO YOU KNOW?

16. Time of day & insolation

17. The sun’s rays are strongest when the sun is overhead
Everyday, the sun appears to move across the sky, When are the sun’s rays at their strongest?
The sun’s rays are strongest when the sun is overhead
noon?
6pm?
8am?

18. the sun’s rays are the strongest at solar noon
*the sun’s rays are the strongest at solar noon. when the rays are the closest to being overhead (vertical)

19. **It is hottest in the afternoon, because the sun is at its highest angle of insolation.

20. *solar noon:when the sun is at its highest altitude in the sky

21. Note:
Even at high noon, most places never get vertical sun rays (rays at exactly an angle of 90.

22. Only the places between the tropic of Cancer (23
Only the places between the tropic of Cancer (23.5 North latitude) & the Tropic of Capricorn (23.5 South latitude) get vertical (90 degree angle) rays (the sun overhead).

23. *At any given time, only one location on Earth is getting the vertical rays.

24. You must remember four important days:
June 21st
September 23rd
December 21st
March 21st

25. *June 21 ( 1st day summer): the sun’s rays are vertical over the tropic of cancer (23.50 N).

26. *September 22 ( 1st day fall): the sun’s rays are vertical over the equator.

27. *december 21st ( 1st day winter): the sun’s rays are vertical over the tropic of capricorn (23.50 S).
Tropic of capricorn

28. *March 21st ( 1st day spring): the sun’s rays are vertical over the equator.

29. The location receiving the vertical rays changes cyclically.

30. A. March 21 b. June 21 c. October 21 d. December 21

If the model of location B represents the apparent path of the Sun observed at the Equator, what is the date at location B?
A. March 21
b. June 21
c. October 21
d. December 21