1. Chapter 7 Water and Atmospheric Moisture Geosystems 6e An Introduction to Physical Geography Robert W. Christopherson Charles E. Thomsen

2. Water and Atmospheric Moisture TOPICS: Atmospheric Stability Clouds and Fog Air masses and Lifting Mechanisms

3. Atmospheric Stability Stable and unstable atmospheric conditions Involves a parcel of air and its surrounding environment in the atmosphere Stable atmosphere: A parcel of air is discouraged from rising Kind of weather normally associated? Unstable atmosphere: A parcel of air is encouraged to rise Kind of weather normally associated?

4. Examples of Stability Figure 7.20 Unstable Atmosphere Parcel of air is encouraged to rise

5. Examples of Stability Figure 7.20 Stable Atmosphere Parcel of air is discouraged from rising

6. Moisture Droplets Figure 7.20

7. Raindrop and Snowflake Formation Figure 7.22 Collision-coalescence process Bergeron process

8. Cloud Types and Identification Figure 7.23 1 2 3 5 6 7 8 9 10 4 2

9. Cirrus Figure 7.23

10. Cirrostratus Figure 7.23

11. Cirrocumulus Figure 7.23

12. Altocumulus

13. Altostratus

14. Stratus Figure 7.23

15. Nimbostratus Figure 7.23

16. Stratocumulus Figure 7.23

17. Cumulus Figure 7.23

18. Cumulonimbus Figure 7.23

19. Cumulonimbus Development Figure 7.24

20. Fog Fog – a cloud layer at or very close to the surface formed when surface air temperatures and dewpt temperature are nearly identical Advection fog – warm, moist air layers moves over a cold surface Evaporation fog – dole air moves over warmer water body Radiation fog – loss of longwave radiation over moist surface

21. Advection Fog Figure 7.25 When warm, moist air moves over cooler body of water, what happens?

22. Evaporation Fog Figure 7.26 Cold air lies over warmer body of water, and evaporation from water surface causes saturation and fog. Also, sea smoke = hazard.

23. Figure 7.28 Radiation Fog Loss of longwave radiation at night over moist surface causes saturation.

24. Air Masses Figure 8.2

25. Atmospheric Lifting Mechanisms Convergent Lifting Convectional Lifting Orographic Lifting Frontal Lifting (Cold and Warm Fronts)

26. Atmospheric Lifting Mechanisms Figure 8.6

27. Global Barometric Pressure Figure 6.11

28. Convection over Florida Figure 8.8

29. Orographic Precipitation Figure 8.9