Spectral Measurements of Solar Irradiance and Radiance in Clear and Cloudy Atmospheres - Short-Wave Solar Radiation in the Earth's Atmosphere - page 119

µ wavelength 0.5 1.5 for total radiation over the shortwave spectral

region (experiments 1, 2 and 4) that is pointing to the strong absorption of
solar radiation in the atmosphere. Thus, the anomalous absorption obviously
reveals itself under conditions of a high content of absorbing aerosols together
with cloudiness of large optical thickness (

m and f s ∼

τ

> 15) and for small solar zenith
angles. Moreover, this effect is not displayed at all in the pure clouds of small
optical thickness.

3.5.4
Dependence of Shortwave Radiation Absorption upon Geographical Latitude
and Solar Zenith Angle

Presented in Table 3.2 are values of parameter f s and absorption R ,which
demonstrate a decrease as they move from tropical to polar regions, which
is in agreement with the analysis results in the studies by Kondratyev et al.
(1996, 1997a, 1997b) and Vasilyev A et al. (1994). This tendency is broken
for the industrial zones characterized with high pollution of the atmosphere
(experiments 3-5) and in case 6 of two-layer cloudiness.
The detailed analysis of the mean monthly data sets of the total solar short-
wave irradiance obtained from the ground and satellite observations during
46 months (from March 1985 till December 1988) has been accomplished in

Fig. 3.20. a Latitudinal dependence of the parameter f s as per Li et al. (1995) ( solid line )
and the values obtained from the airborne observations ( dashed and dotted lines ). Squares
point to the values of f s in total shortwave spectrum, circles point to the wavelength 0.5 µ m;

b Dependence of the parameter f s of cosine of the solar incident angle as per Imre et al. (1996)
(nomograph) and the values obtained from the airborne observation. Squares indicate the
total spectrum data; triangles indicate the data at the wavelength 0.5

µ m