APPARENT PATH OF THE SUN

1. APPARENT PATH OF THE SUN How does the Sun’s path affect the amount of energy received on Earth?

2. HOMEWORK • Textbook: read pages 257 – 260. • Do questions 17, 23-31.

3. SUN • RISES IN THE EAST . . . SETS IN THE WEST

4. ANGLE OF INSOLATION • Insolation:Incoming Solar Radiation is the sun's energy that enters the earth's atmosphere and surface. • Angle of Insolation: the angle at which the sun’s rays strike the earth's surface. • Intensity: a measure of the amount of radiation that strikes a unit area of the earth's surface.

5. FACTORS THAT INFLUENCE THE AMOUNT OF ENERGY RECEIVED BY THE SUN • Angle of Insolation • lower in the mornings and evenings • Higher in the afternoons • Duration of Insolation • In NY, Sun is out for 15 hours in Summer • In winter, Sun is out only 9 hours • Latitude of maximum insolation • North and South Poles are much colder than the Equator.

6. FACTORS THAT INFLUENCE THE AMOUNT OF ENERGY RECEIVED BY THE SUN • Intensity of Insolation • Higher the angle of insolation, the greater or stronger the amount of energy • Lower the angle, the weaker the amount of energy.

8. High Angle – Sun is directly overhead

9. High Angle – Sun is directly overhead with high intensity of energy - short shadows

10. LOW ANGLE – Sun is low in the sky –low intensity of energy

11. LOW ANGLE – Long shadows, lower intensity of Sun’s energy

12. IMPORTANT DATES • JUNE 21: SUMMER SOLSTICE • DECEMBER 21: WINTER SOLSTICE • MARCH 21: VERNAL EQUINOX • SEPTEMBER 21: AUTUNM EQUINOX

13. IMPORTANT LATITUDES • ZENITH – POINT DIRECTLY ABOVE • JUNE 21 – 23.5 NORTH (Tropic of Cancer) • DECEMBER 21 – 23.5 SOUTH (Tropic of Capricorn) • MARCH 21 & SEPTEMBER 21 - 0 (Equator)

14. SUN’S PATH

15. SUN’S PATH

16. SHADOWS • In New York • Sun’s Path is always in the southern sky. • Shadows are always opposite the Sun • Low Sun, Long shadows • High Sun, short shadows

17. SHADOWS

18. High Noon, December 11 at Reykjavik

19. High Sun, Short Shadows