A.d.vi. Solar flux and zenith angle
|
The solar flux integrated over all wavelength at the top of
atmosphere is depend on season, latitude and local
time.
In this section, we show formulation of as a function of local time
at a specified season and latitude.
Suppose that is solar constant on the mean orbital radius
of Planet, and is the radius of
orbit and its mean value, is solar zenith
angle, is latitude, is the solar
inclination, is the hour angle
(= , is length of
day ).
is represented by using these variables
as follows.
(c.f., Ogura, 1999).
and are given as follows.
where is the longitude relative to the
perihelion, is the semimajor axis of orbit, is the eccentricity, is
the declination, ω is the true anomaly,
and is the longitude of vernal
equinox relative to the perihelion.
By introducing the areocentric longitude of the sun ,
is rewritten as follows.
|
(A.54) |
where = 0.093, = 25.2°,
= 100°, and = 591
Wm-2.
The value of is derived from the figure 1-1 of
Carr (1996).
|