1. Environmental Sustainability Studies 111 INTRODUCTION TO THE ENVIRONMENT Lecture 4 – The Earth’s Component: Atmosphere

2. The Atmosphere: structure Source: http://www.theozonehole.com/images/atmosphere.gif

3. Functions of the atmosphere Life sustaining functions in Troposhere: –Oxygen: for respiration –Carbon dioxide for photosynthesis –Nitrogen for protein synthesis –Moisture for a variety of chemical reactions Protection functions: ozone (in stratosphere) blocking harmful UV rays; shield us from solar winds Create temperature balances Troposhere plays host to all our climate weather phenomena...water vapour & aerosols

4. Composition of the atmosphere Nitrogen: 78.02% Oxygen: 20. 95% Argon: 0.93% Carbon dioxide: 0.035% Neon: 0.0018% Helium: 0.0005% Methane, krypton, xenon, hydrogen....

5. The Atmosphere: temperature, altitude and air pressure variations Source: www.wyckoffschools.org/.../earthatmosphere.htmwww.wyckoffschools.org/.../earthatmosphere.htm

6. Climate and weather factors Location: latitude, longitude & altitude Seasonal changes Land & water contrasts Ocean currents Air pressure & wind Humidity Precipitation & forms of precipitation Weather extremities: cyclones, hurricanes, El Nino, La Nina Air quality & human influences

7. Global Air Circulation Source: www.mynasadata.larc.nasa,gov

8. El Nino Source: www.junglephotos.com/.../othersatimages/elnino.jpg

9. Cycles in the atmosphere

10. Big Picture – Planetary context for earth- atmosphere energy-matter exchange …Heat Budget

11. Carbon Cycle Source: www. theresilientearth.com

12. Carbon sinks Geological sinks: –Vast amounts of carbon trapped in sedimentary rocks like limestone, dolomite & chalk –Also in fossil fuels deposits Biological sinks: –Oceans, atmosphere, soil & plants –These sinks primarily responsible for current build-up of CO 2

13. Oxygen Cycle Source: http://www.acsa2000.net/sites/10ba/Photosynthesis.jpg

14. Some questions How can your understanding of the structure of the atmosphere help in assisting carbon reduction efforts? The atmosphere is an important carbon sink. Briefly explain how this function is/can be jeopardized if we continue emitting more CO 2 into the atmosphere. Briefly explain how atmospheric processes cause and influence different natural environments on earth.

15. Diagrammes and animations Please visit http://earthguide.ucsd.edu/earthguide/diag rams.html for explanatory notes, diagrammes and animations of the earth’s realms and processes! http://earthguide.ucsd.edu/earthguide/diag rams.html