1. Thermal Response II Current News and Weather Surface Energy Balance
Controls of Air Temperature
Tropics vs. Middle and High Latitudes
For Next Class: Read Chapter 6
Exam 1 on Wednesday (2/7)! (Review sheet is posted)

7. Discussion
1. Why do maritime locations typically exhibit more moderate climates (cooler in summertime, warmer in winter) than continental locations at the same latitude?

8. Land–Water Heating Differences
Figure 5.7

9. Thermal Response and Specific Heat
Maritime and Continental Climates
Maritime climates: immediately downwind of the ocean, and experience much less contrast between average winter and summer temperature
Continental Climates: well inland, experience a much greater contrast between winter and summer temperature
© AMS

10. Latitude and Temperature
Figure 5.4

11. Discussion
2. What is the Bowen Ratio? Which locations are characterized by high Bowen Ratios and which have low ones?

12. Heat Imbalance: Atmosphere vs. Earth’s Surface
Sensible Heating
The Bowen Ratio compares how heat at the Earth’s surface is divided between sensible heating and latent heating
Varies from one place to another
Depends on amount of surface moisture
Surface energy budget through the course of a year
© AMS

13. Bowen Ratio Bowen ratio = (sensible heating)/(latent heating)
High Bowen ratio implies more sensible heating than latent heating (i.e., deserts)
Low Bowen ratio implies more latent heating than sensible heating (i.e., oceans or water bodies)

14. Heat Imbalance: Atmosphere vs. Earth’s Surface
© AMS

15. Surface Energy Balance
Figure 4.15

16. Albedo (Reflectivity of a Surface)
Figure 4.5

17. Simplified Surface Energy Balance
NET R =
+SW (insolation)
–SW (reflection)
+LW (infrared)
–LW (infrared)
Figure 4.16

18. Daily Radiation Curves
Figure 4.14

19. Temperature
Where is the coldest location in the world likely to be in January? Why?
In July? Why?
Which location has the greatest annual temperature range? Why?

20. January Temperatures
Figure 5.14

21. July Temperatures
Figure 5.17

22. Global Temperature Ranges
Figure 5.19

23. What is Wind?

24. What is Wind? Horizontal movement of air
Moves from areas of high pressure to areas of low pressure
Above the surface, winds are geostrophic (parallel to isobars) and result from a combination of two forces:
Pressure Gradient Force (High to Low)
Coriolis Effect (Right in NH, Left in SH)

25. Pressure Gradient
Figure 6.7

26. Coriolis Force
Figure 6.9

27. Upper Level Winds
What are the two forces that influence wind direction in the upper levels of the troposphere (i.e., above 12,000 ft or ~600 mb)?

28. Surface Winds
What are the three forces that influence wind direction at the surface?