The ground temperature is calculated by the 1D thermal conduction equation.
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(A.55) |
where is the ground temperature (K), is the soil density
(kgm-3), is the specific
heat
(Jkg-1K-1), and
is the thermal conductivity
(Wm-1K-1).
The surface temperature is given as .
The boundary condition at the surface is given as follows.
|
(A.56) |
where is the solar radiative flux at the
surface (the sign of downward flux is positive), is
the surface albedo, is the net infrared radiative
flux emitted from the surface and is the sensible
heat flux (the sign of upward flux is positive).
The lower boundary of the ground surface is given as a insulation boundary.
The values of soil density, thermal conductivity and specific heat are
same as those of Kieffer et
al. (1977) standard model, where =
0.25, = 1650 kgm-3,
= 588
JK-1kg-1, =
7.63×10-2
JK-1m-1sec-1.
By using these values, the thermal inertia is
272
Wm-2sec1/2K-1
and the diurnal skin depth of is about 8.2 cm.
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