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4.c.i. Intensity of convection
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Let us estimate
the depth of conduction layer 
and potential temperature difference in conduction layer
by using (2) and
(4).
The sum of net infrared radiative heating due to
CO2 and sensible heat flux is
about 20 Wm-2 in the day time
(Figure 12f (right panel)).
The value of turbulent diffusion coefficient in
the thermal boundary layer is about
the same as that for the dust-free case, i.e.,
about 15
m2sec-1,
(Figure 12b).
Substituting these values into (2),
the vertical gradient of
horizontal mean potential temperature in the conduction layer
is estimated as -0.1 Km-1.
This value is consistent with the simulation result
shown in Figure 14.
Further using these values, (4)
can be rewritten as follows;
From this expression, we obtain
˜ 60 m and
˜ 6 K.
(The corresponding results of our simulations are
< 50 m and
˜ 3 K.)
Compared to the estimated values of the dust-free case,
is about the same, but
is about 2 K smaller.
Potential temperature deviation of
ascending convective plumes is estimated by using
(5).
From Figure 14,
we can adopt
˜ 40 m,
˜ 3 K, and
˜ 5000 m.
We assume
the magnitude of tubulent diffusion coefficient
is roughly the same as that of the dust-free case
(
˜ 15 m2sec-1).
Substituting these values into (5),
we obtain
potential temperature deviation of plumes
as follows;
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Figure 14:
Vertical profile of horizontal mean potential temperature
below the height of 1 km at LT=14:00 of the
6th day of the dusty case.
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