1. isobars
820 mb
860 mb
900 mb
90oF
70oF
Cold
Warm
780 mb

2. Land breeze

3. 3

4. Monsoon

5. wind system is one that
changes direction seasonally,
blowing from one direction in
summer and from the opposite
direction in winter

6. Summer  where is the pressure higher
between land and ocean?
Warm surface  air rising  low surface pressure
Wind
Cool surface  air sinking  high surface pressure

7. monsoon wind system is one that changes direction
seasonally, blowing from one direction in summer and
from the opposite direction in winter
Stepped Art

8. Valley breeze

9. -Upslope/valley breeze forms as solar radiation heats the
slope of mountain
Q: What would happen for the
air adjacent to the slope from
the heating?
SW
750 mb
H
L
800 mb
850 mb
850 mb
900 mb
900 mb
9
Stepped Art

10. Katabatic
winds

11. Katabatic winds decent down a mountain slope
Q: What would happen ? conditions for katabatic winds ?
be optimal
LW
750 mb
750 mb
800 mb
800 mb
850 mb
850 mb
900 mb
900 mb
11

12. Katabatic winds decent down a mountain slope
Optimal conditions
o snow-covered elevated plateau
o generates a horizontal pressure gradient
H
PGF
LW
L
750 mb
800 mb
850 mb
900 mb
12

13. 13
Fig. 7-13, p. 179

14. Advection issues on eddy flux
measurements

15. Tower-1
Tower-2

16. Chinook

17. 1.The air at point A in the figure below will be
WARMER COLDER than at B and will have a
HIGHER LOWER dew point.

18. 2. Lifting by topography
Fig. 5-14, p. 119

19. chinooks are descending, warm and dry
winds on the leeside of a mountain range
19

20. Santa Ana
winds

21. Santa Ana winds created wildfire
21

22.  hot and dry winds that often sweep through the LA Basin in the fall and winter
winds descend from hot desert
terrain down to the L.A. Basin 
parcel becomes warmer and drier
because of compression heating
need a strong high
over southwestern U.S.
22
Stepped Art

23. Single-Cell Model
Three-Cell Model

24. Single-cell model of General Circulation
If you assume
earth is uniformly covered by water
sun is directly over equator
no rotation
you will end up with a single cell pattern
called the Hadley Cell
warm air rises at the equator, cold air
sinks in the poles
Q: This single cell has never observed, what
important processes have we neglected?

25. Three-cell model of General Circulation
Hadley cell (0-30o); Ferrel cell (30-60o); and Polar cell (60-90o)
Q: How can we draw the
basic characteristics of
the general circulations?

26. 1.
3. draw wind directions by
taking into account CF
draw five belts at 0, 30, and 60 degree and
mark L and H on each of them
NH, deflection to right
SH, deflection to left
2. draw PGF from H to L
Polar H
60o
30o
L
H
Subpolar low L
Subtropical high
60o
H
30o
PGF
L Intertropical convergence zone L
0o
PGF
0o
30o
H
60o
Subtropical high
L Subpolar low L
Polar H
H
30o

27. Hadley cell
Thermal cell