Weather…Climate… Climate Change… Ozone Depletion…

1. Weather…Climate…Climate Change…Ozone Depletion… …what does it all MEAN?

2. Question: What’s in the atmosphere? • N2 (78%) • O2 (21%) • Ar (0.9%) • WV • CO2 • O3 • Particulates (greenhouse gas) (greenhouse gas)

3. Thermosphere

4. TROPOSPHERE • Gases here moderate flow of energy to E. • 10 mi thick @ tropics; 5 mi thick @ higher lats. • Contains all the WV & clouds. • Weather occurs here! • Temp ↓ as altitude ↑. • Pollutants can rise to top within days... • TROPOPAUSE caps it...temp stops decreasing.

5. (higher...) STRATOSPHERE • Temp ↑ as altitude ↑... • Contains O3 (it absorbs radiation). • Persistent substances

7. What happens to TEMP as you go farther away from E?Why does it warm up in the stratosphere?

8. What happens to the TEMP as you move farther from E?

9. Good to know... • Weather: day-to-day variations in temp, precip, wind, pressure, & humidity. • Climate: long-term regional weather patterns. • Factors affecting climate: • Latitude • Atmospheric circulation • Oceanic circulation • Topography • Solar activity • Volcanic activity

10. Latitude

11. Latitude • LOW latitudes close to equator receive more direct (vertical) rays; more concentrated E per surface area. • No winter…no summer…all hot. • HIGH latitudes receive less direct (oblique) rays; less concentrated E per surface area. • Wider temp range, seasons!

12. Warm air rises (low pressure...)Cold air sinks (high pressure...)Pressure flows from HIGH to low Atmospheric Circulation (wind…)

14. Latent Heat • Warm air holds more WV than cool air • Warm air rises (less dense) • As moist/warm air rises, it cools & WV condenses to liquid…clouds form… • Latent heat (“trapped” in WV) is released • Energy source for t-storms, tornadoes, hurricanes. • QUESTION: will increased temps lead to more WV…more latent heat…resulting in more intense severe weather?

15. How OCEANS affect temp... • HEAT CAPACITY: water stores heat more effectively than solid earth (heats up & cools more slowly than land). • HEAT TRANSFER: ocean currents carry warm equatorial water towards poles. • SOURCE for WV: when wv condenses in the atmosphere it releases latent heat.

16. Surface Currents

17. One cycle: 1,000 years

18. El Nino-Southern Oscillation (ENSO)

20. Solar Maximum • - Increased UV • - Increased O3 • - Increased temps

21. - SO2 gas reaches • upper atmosphere. • SO2 & dust & WV • form haze. - Haze reflects sun- light, global temps decrease.

22. …the seasons! And finally…

23. Greenhouse Effect • Analogy: sunlight pours into your car & heats up the interior (gets absorbed by seats, dash, etc) as it’s converted from light energy to heat energy (IR). • The light energy escapes back out through the glass...but the heat energy is blocked by the glass and so cannot leave the car. • Much like a “greenhouse.”

24. Greenhouse Effect • The Greenhouse Gases - WV, CO2,CH4,& N2O are analogous to the glass in a greenhouse. • Light energy from Sun passes through them, strikes E and is converted to heat energy (IR)...the converted IR is absorbed and re-radiated back into the troposphere by the GHGs.

25. Your diagram goes here!

26. ABSORBED: 70% REFLECTED: 30%

27. An important 70%... • The solar energy not reflected back into space (70%) gets transferred to the atmosphere as IR energy... • This warmed-up air becomes less dense, rises, and creates air currents called convection cells.

29. ...it’s actually a good thing... • The greenhouse effect moderates the temp and makes it warm enough for many ( a word that often leaves you guessing) life forms to exist...

30. ...a force to be reckoned with. • HOWEVER... If the concentration of these GHGs changes, their insulating effect changes also...and so will our climate.

31. Enhanced Greenhouse Effect • 1958: Charles Keeling begins measuring CO2 levels on Mauna Loa

32. Anthropogenic warming • Warming of the Earth derived from human activity

33. ...climate change is such an important issue today because we depend on those orgs for vital goods & services we need to survive...

34. If the global climate changes, can these ecosystems change with it - so those vital goods & services continue?

35. CLIMATES • ...remember how ecosystems & biomes result from different combo’s of temp & precip? • ...and the orgs that inhabit a particular biome are adapted to those limits? • HUMANS can live anywhere (we don’t have to adapt – we control the environment...)

36. Past Climates • Global surface temps fluctuate! • This chart is modern... stats come from actual weather stations.

37. ...but what about long ago? • Proxies are used to provide info about ancient climate conditions. • Pollen deposits...marine sediments...coral...ice cores... historical data…

38. Pollen!

39. Biological Changes in fossilized orgs (type & amount) Oxygen isotope concentrations in shelled remains Inorganic Clay mineralogy Aeolian dust Marine sediments

42. Coral • “Greer and Swart were investigating the relationship between non-radioactive or stable isotopes of oxygen in the calcium carbonate of the coral. The ratio of normal to heavier oxygen depends on the temperature of the water the coral grew in and its salinity. In warmer water, the coral incorporates more of the normal oxygen into its structure, but if the water is cooler, the coral will incorporate a higher percentage of the heavier oxygen isotope.”

47. Medieval Warming PeriodLittle Ice Age

48. What does it MEAN? • E’s climate has oscillated between ice ages and warm periods. • Milankovich cycles : Earth rotational & revolutionary movements combine to affect global climate. • Theory: Ice ages are caused by 100,000 year coincidences of these cycles.