Radiation, Heat, and Temperature

1. Radiation, Heat, and Temperature

2. Aphelion Perihelion

7. Great Circle Largest possible circle on a sphere Formed by passing a plane through the center of a sphere Great circles bisect sphere (cut it in half) Great circle routes are the closest distance between two points on surface Example: Equator

8. Any two great circles must bisect each other Blue circle cuts red circle in half (and vice-versa)

9. Latitude “lines” identify north-south location on a sphere All latitudes are “small circles” except for the equator

10. LONGITUDE Longitude “lines” (meridians) identify east-west location on a sphere Each longitude is half of a great circle (example: 90°west and 90°east)

11. CIRCLE OF ILLUMINATION A great circle dividing sunlit and dark hemispheres of Earth (day vs. night) The circle of illumination is not usually oriented along Earth’s polar axis.

12. TIME DEPENDS ONLY ON LONGITUDE Looking down on North Pole

13. SEASONS

15. APPARENT SOLAR PATH AT DIFFERENT LATITUDES Chapter 3, pp. 60–66

16. Cross-Quarter Days Oct 31 Aug 1 Feb 2 May 1

18. Solar Radiation Spectrum

19. Sun vs. Earth Infrared

21. Rayleigh Scattering longer waves are not scattered shorter waves are scattered

22. Rayleigh Scattering

23. Rayleigh Scattering Cyan sky is mix of visible intensities coupled with eye sensitivity

24. Rayleigh Scattering

25. Setting sun appears red because shorter visible wavelengths (blue through yellow/orange) are scattered

26. Mie Scattering all wavelengths are scattered

27. Mie Scattering

28. 20.1 (Mie)

29. Low sun = low transmissivity (longer path of radiation through atmosphere)

31. Solar Constant Solar “constant” decreases with increasing distance from sun

45. Clouds and Solar Radiation

46. Net Radiation by Latitude

47. AVERAGE JANUARY TEMPERATURE (°F)

48. AVERAGE JULY TEMPERATURE (°F)