1. CH 15 – Air, Weather, Climate
Pages: 323 – 329;
+ Inconvenient Truth

2. Patterns?

3. F

4. Weather or Climate?
Weather: short-term atmospheric events at a specific locality
Climate:

5. Weather: short-term atmospheric events at a specific locality
Climate: long-term patterns of weather over broad regions

6. Weather and climate in middle GA?

7. Weather and climate in middle GA?
warm, humid summers (thunderstorms)
long growing season
mild winters
rainfall - winter

8. The sun is the climate engine

9. Infrared radiation derived from sunlight is the climate engine

10. Weather and Climate the result of
solar radiation
ambient temperature

11. Weather and Climate the result of
solar radiation
ambient temperature
Moisture (evaporation and transpiration)
Wind (transfer of mass between low and high pressures)

12. Basic atmospheric structure
Stratosphere – km
Troposphere – 0-10 km
Basic atmospheric structure

13. Structure of atmosphere
limited water vapor
Weather and Climate constrained by atmosphere

14. Structure of atmosphere

15. 4 principles of Climate
curvature
tilt

16. A hypothetical continent

17. 4 principles of Climate
1. The sun heats unevenly.
curvature
tilt

18. Solar Radiation heats the earth (unevenly)
Sun’s rays
Atmosphere
Large surface
area
40% insolation at poles
compared to tropics
Small surface area
Equator
Earth

19. angle of sunlight UNlabeled
Consider the Equinox
solar equator = latitudinal equator

20. 40
Clouds and rainfall keep
temperature uniform
across the tropics 30 20 10
Mean annual temperature °C
-10
-20 10 20 30 40 50 60 70 80
Degrees latitude

21. The angle of the earth’s axis is responsible for seasonal variations on the earth.

22. angle of sunlight UNlabeled
Consider the Equinox
solar equator = latitudinal equator

23. 22 September
21 March

24. 21 June

25. 21 December

26. Solar equator shifts N and S
influencing rainfall

27. Solar Equator
Heated air rises, cools, releases rain

28. Relationship between solar energy and rainfall?
relative humidity

29. relative humidity
Water evaporates
heated, moisture-laden
air rises

30. relative humidity air pressure and temperature drop
rising air expands and
cools

31. relative humidity Relationship between solar energy and rainfall?
5. Condensation begins
(moisture holding capacity
decreases)
6. precipitation may result

32. Solar Equator
Heated air rises, cools, releases rain
Low pressure at surface (Tropical Lows)
surface air moves in from North and South

33. 30 N & S of solar equator
Cooled air sinks, warms, ‘holds more’ moisture

34. 30 N & S of solar equator
Cooled air sinks, warms, picks up moisture
High pressure at surface
deserts in the Horse Latitudes

35. development of a Hadley cell

36. all three hadley flow and winds

37. 1. Solar Radiation heats the earth (unevenly)
latitudinal gradients in temperature
Hadley cells determine distribution of rainfall and pressure
tropical lows, subtropical highs
Major forest types and deserts

38. Biomes

39. 2. The Earth Spins
Speed at
North Pole?
Equator?

40. The Earth spins ‘The Coriolis Effect’ Predominant Winds
Tropical easterlies (0-30º)
Temperate westerlies (30º-60º)

42. Hurricane Season
ITCZ

43. Climate
3. Wind pushes water creating gyres

45. Wind pushes Water Nova Scotia - England
Ocean currents distribute energy and modify coastal climates

46. Driest deserts in the world lie on the west coasts of continents

47. Annual World Precipitation

48. Regional Climatic Influences
Topography and Geography modify patterns generated by principles 1-3

49. Regional Climatic Influences
Topography and Geography modify pattterns generated by principles 1-3
a. The Rain Shadow Effect
b. Altitudinal Effects
c. Continental effects (oceans mediate extremes)

50. Regional Climatic Influences
Pacific NW – Olympic and Cascade mtn ranges
The Rain Shadow Effect

51. Temperate “Rainforests”

52. Eastern Oregon dry grasslands

53. e.g. rain shadow in N. A.
North American Deserts

54. Regional Climatic Influences
Topography and Geography modify pattterns generated by principles 1-3
a. The Rain Shadow Effect
b. Altitudinal Effects
c. Continental effects (oceans mediate extremes)

55. Altitudinal Effects
e.g., Cloud Forest biome
of Trinidad

56. Altitudinal Effects
Even a few hundred meters can significantly alter community type.

58. year-round 100% humidity

59. Regional Climatic Influences
Topography and Geography modify pattterns generated by principles 1-3
a. The Rain Shadow Effect
b. Altitudinal Effects
c. Continental effects (interiors experience temperature extremes)

60. Variation in Climate
Determines distribution of large scale assemblages of organisms

62. A hypothetical continent