section 1: introduction 1.1 where are the tropics and what makes them special? 1.2 the amount of...
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Section 1: INTRODUCTION
1.1 Where are the tropics and what makes them special?
1.2 The amount of energy received by the earth
1.3 Moisture in the tropics
1.4 Basic equations
1.1 Where are the tropics and what makes them special?
Arbitrary definitions for where they are:
Geography: Tropics are the region of the earth bounded by the tropic of Cancer (23.5oN) and the tropic of Capricorn (23.5oS). These are the latitudes
where the sun reaches the zenith just once a year at the summer solstices.
Equal Halves: The region between 30N and 30S would divide the earth into two equal halves. Defined this way, the tropics would be the source of all the
angular momentum of the atmosphere and most of the heat. But this is not meteorologically sensible.
Processes: Riehl (1979) chose to define the “meteorological” tropics as those parts of the world where atmospheric processes differ significantly from
those in higher latitudes (see next slides).
Riehl (1979) Climate and Weather in the Tropics, Academic Press.
Figure 1.1
Contrasting processes
Land and ocean contrasts
Figure 1.2: Markedly non-uniform distribution of land and ocean areas in the tropics may be expected to have a large influence on the meteorology there
No Walls!
Annual Mean Rainfall
Figure 1.3
Mean Meridional Circulations
Figure 1.4
1.2 The amount of energy received by the earth
Figure 1.6
Figure 1.5
Solar Radiation Received at TOA
Outgoing radiation
Solar absorbed
Northward transport of energyNorthward
transport by atmosphere
Figure 1.7
1.2 The amount of energy received by the earth
1.2 The amount of energy received by the earth
Figure 1.8(a)
1.2 The amount of energy received by the earth
Figure 1.8(b)
Figure 1.9
1.2 The amount of energy received by the earth
1.3 Moisture in the tropics
Figure 1.10
Figure 1.11
1.3 Moisture in the tropics
Figure 1.12
1.3 Moisture in the tropics
1.3 Moisture in the tropics
Figure 1.13(b)
Figure 1.13(a)
Figure 1.14
1.3 Moisture in the tropics
1.4 Basic equations
0
x
fvDt
Du
0
y
fuDt
Dv
P
RT
p
0
pSy
Tv
x
Tu
t
TP
T
P
T
PC
RTS
pp
where
0
py
v
x
u
Adiabatic, Frictionless Equations in Pressure Coordinates