meridian plane as a common reference..
21
[1 0 0 0 ]
|0 cos2a -sin 2a 0|
Rot(a) - - ,
10 sin2a cos2a 01 (6)
[o 0 0 lj
Furthermore, R sp ( 2co) is the specular reflection function and co is the incident or reflection angle to
the facet [5].
2. REFLECTANCE ANALYSIS OF AIRBORNE POLDER DATA
Preliminary analyses on the airborne POLDER data over the Mediterranean Sea was already
done by [ 6], [7]. We have computed the theoretical reflectance for two types of aerosol models ,
namely , the log-normal type aerosol model and Junge type aerosol model. Furthermore, we only
consider a spherical water aerosol particle whose refractive index m= n -i k in this study. The log
normal size distribution for aerosol particles is given by Eq.(7) [3].
n(r) =
:eX p[-»^]
Xogojljt 2(logcry
(7) ,
where a, and r 0 are the geometric standard deviation, and geometric mean radius of the aerosol
particles. The two sets of optical parameters ( a = 2.99, and r 0 = 0.005) and ( a = 2.51, and r 0 = 0.30)
correspond to a water-soluble aerosol model and an oceanic aerosol model, respectively.
On the other hand , the size distribution of the Junge type aerosol model is given by Eq.(8)
[4].
<r)
f
v + l
C-10
-(v + l)
Ct
0
0.02 f.im ^ r £ 0.1 ¡urn
0.1 jum is r ^ 10 /mi
r < 0.02 f.im, r > lOjUra
( 8 ) ,