2.1 Energy Relationships and The Biosphere

1. 2.1 Energy Relationships and The Biosphere

2. Flow of Energy in the Biosphere • The biosphere is maintained by a constant flow of energy from the sun • Net radiation budget is the difference between incoming and outgoing solar radiation

4. Energy Relationships and the Biosphere (a) Latitude(b) Characteristics of the biosphere The amount received by a region (isolation) depends on:

5. Angle of Inclination • Is the degree by which the poles are titled from the perpendicular plane of orbit

6. Angle of Incidence • Is the angle at which the sun’s rays hit the surface of the earth • It depends on latitude • It is affected by the tilt of the earth axis which is 23.5°

8. because of the tilt the earth: • The suns rays: • strike the equator directly …at 0° • are less direct at higher latitudes • cause uneven heating; resulting in weather conditions • There are seasons

9. Seasons • Are caused by the tilt of the Earth’s axis • Change when the northern hemisphere is: • Tilted toward the sun = summer • Tilted away from the sun =winter Summer Winter

10. Solstice • is the shortest and longest day of the year • Summer Solstice: • is the longest day of the year (most hours of daylight) • June 21st • Winter solstice • is the shortest day of the year • December 21

12. Equinox • Is when the center of the sun is over the equator • Vernal Equinox • is the beginning of spring • Autumnal Equinox • Is the beginning of fall • Is when the equatorial regions have 12 hours of daylight and 12 hours of darkness

13. Solar Energy • Is either absorbed or reflected

14. Solar Energy Absorbed • Can be converted to chemical energy by photosynthesis • Drives water cycle

15. Hydrologic Cycle (water cycle) • Water evaporates from lakes, oceans, etc. and from plants (TRANSPIRATION) • water rises, cools, and condenses • it falls to the ground as precipitation • whenever water changes phase, thermal energy is either released or absorbed • this movement of thermal energy help to keep the average temperature of Earth relatively stable

16. Water Cycle

17. Solar Energy Reflected • The amount depends on the albedo of the surface • Aledo is the degree to which materials reflect solar radiation • Light colors have a high albedo and reflect

18. snow, ice, water, clouds high albedo = soil, dark rocks, forests, dust low albedo =

19. Natural Green House Effect • Is caused by green house gases in the troposphere trapping heat that is reflected from earth • Green house gases • Methane • Carbon dioxide • Water vapour • These keep the average global temperature at 25 degrees

21. There are 4 Main Greenhouse Gases

22. Assignment • Page 369 # 1-12