Geoscience Reference
In-Depth Information
(a
) DJF
300
400
2
500
600
4
700
6
8
800
10
900
12
90°N
60°N
30°N
Equator
30°S
60°S
90°S
(b
) JJA
300
400
500
2
600
4
700
2
6
800
8
12
14
900
10
90°N
60°N
30°N
Equator
30°S
60°S
90°S
Figure 2.30 Zonal mean specific humidity climatology for (a) December-
January-February (DJF) and (b) June-July-August (JJA). Units are 10
−3
kg
H
2
/
kg
air
.
that specific humidity also decreases exponentially with height, to irst-order
approximation.
• Values are largest deep in the tropics, and decrease toward both poles.
• The summer hemisphere is more moist than the winter hemisphere, and
seasonal differences are more pronounced at higher latitudes.
