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Fig. 3.15. Spectral dependence of the radiative flux divergences. The identification of the
hematite absorptionband in spectra. Above theKara-KumDesert: 1 - the airborne sounding
12th October 1983 under dust storm conditions; 2 - 10th October 1983 under dust gaze
conditions; 3 - 23rd October 1984, the pure atmosphere. Above Ladoga Lake: 4 - airborne
sounding 29th April 1985 (snow surface); 5 - the airborne sounding 16th May 1984 (water
surface). Spectral dependence of the imaginary part of the complex refraction index of the
hematite according to Ivlev and Popova (1975) is in the right-hand upper corner
flux divergences above the desert obtained during the beginning of the dust
storm (12 October 1983), with the dust gaze (10 October 1983), and in the pure
atmosphere (23 October 1983). The band of the selective aerosol absorption is
apparent in corresponding curves, and it is possible to attribute this band to
theferrousoxidesmixture(thecomponentofthesand)called“ hematite ”. The
radiative flux divergences of the soundings above Ladoga Lake (29 April 1985
above the snow and 16 May 1985 above the water), where the mentioned band
is absent, are presented for comparison.
Concerning the “hematite”, it is important to point out that the concrete
substance Fe 2 O 3 usually implied under this term has the maximum of its
absorption in theUVspectral regionanddoes not have the apparent absorption
selectivity as per the results of Ivlev andPopova (1975), Shettle (1996), and Ivlev
and Andreev (1986). However, the authors of the study by Ivlev and Andreev
(1986) have mentioned other ferrous oxides and hydroxides demonstrating
absorption bands similar to the one shown in Fig. 3.15. Not only Fe 2 O 3 but
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