1. Aim: How do the intensity and angle of insolation relate?

2. Why is Newman sweating so much but not Seinfeld?

3. Which City A or B is experiencing more heat? Why?
30º A
90º
Demo with globe and tape down two thermometers put next to a heat lamp.

4. How do we define insolation?
Insolation (Incoming SOLar radiATION) is a term that is used to refer to the radiation from the Sun that is received by Earth. Very hot objects, like the Sun, give off radiation in the form of short waves. The angle at which the Sun’s rays strike Earth’s surface is referred to as the angle of insolation. Because Earth’s surface is curved, the Sun’s rays strike it at angles ranging from 0º to 90º. At locations where the Sun is directly overhead (at zenith), the Sun’s rays are perpendicular and they strike the Earth’s surface at an angle of 90º. Rays that strike Earth’s surface at a 90º angle are called direct or vertical rays. Vertical rays provided the greatest intensity of insolation because the insolation is concentrated over the smallest area which receive more heat energy. As the Sun’s rays become slanted (indirect rays) and less direct, the amount of insolation is spread over larger and larger areas and the intensity of insolation decreases.
1a) Insolation– Incoming SOLar radiATION from the sun that is received by Earth
Depends on intensity and angle of insolation
1b) Intensity of insolation– strength of the suns rays (strong or weak)
1c) Angle of insolation – angle of which the sun’s rays strike Earth curved surface.

5. 2) How does the angle of the sun affect heating?
Angle of Insolation
Direct sunlight (vertical rays) (Perpendicular rays)
Sun is overhead at a 90° angle sunlight hits a small area on earth’s surface
Less intense heating
Indirect sunlight (slanted rays)
More intense heating
30° angle sunlight hits a large area on earth’s surface
City A
City B

6. As the angle of insolation increases, the intensity increases
3) Describe how the intensity of insolation changes as the angle of insolation increases?
Intensity of Insolation
0° Angle of Insolation 90°
As the angle of insolation increases, the intensity increases

7. 4) Describe the factors that affects insolation
2. Latitude – due to Earths curved surface, more intense heat occurs between Tropic of Cancer (23.5°N) & Tropic of Capricorn (23.5°S) higher angle of insolation - Higher latitudes (Poles): colder – less intense heat & lower angle of insolation
23.5 °N
Tropic of Cancer 0°
Equator
23.5 °S
Tropic of Capricorn

8. As Latitude increases, the intensity and angle of insolation decreases
5) Describe how the intensity and angle of insolation changes as your latitude increases?
Intensity/angle of Insolation
0° Latitude 90°
As Latitude increases, the intensity and angle of insolation decreases

9. 6) How does the time of day affect the angel of insolation?
3. Time of Day – Angle of insolation and intensity is greatest at solar noon and lowest at sunrise and sunset
Solar noon – sun is highest in the sky
Solar Noon
6 A.M.
6 P.M.
12 P.M.
9 A.M.
3 P.M.
Angle and intensity increases from sunrise to solar noon
Angle and intensity decreases from solar noon to sunset
60º
60º
90º
30º
30º 0º 0º

10. Intensity/angle of Insolation
7) How does the intensity and angle of insolation change based on the time of day?
Intensity/angle of Insolation
Sunrise Noon Sunset

11. Summary Activity 1. 2. 3. 4.

12. Extra Questions