Electronic Material Properties - und Geowissenschaften ...

As an example, Fig. 2 shows the chemical composition of particles between 1 and
1.5 µm in diameter as a function of measurement altitude over Tinfou for May 19, 2006,
11:24 to 11:42 h. On this day, the mineral dust layer extended up to approximately 4.5
km. The composition of the layer was quite homogeneous, except the sulfate-silicate
mixtures on the ground and at the top of the layer being more abundant than within. The
latter indicates anthropogeneous influence in the boundary layer as well as in the
tropospheric background. On the other hand, the layer was not homogeneous in the
horizontal as is shown by Fig. 1. 140 km to the north east, a significantly higher content
of calcium-bearing particles can be detected, appearing as a mode around 3 µm
diameter.
elevation, m a. s. l.
5,000
4,000
3,000
2,000
1,000
iron rich
titanium rich
carbonates
other calcium rich
gypsum
halite
0.00 0.20 0.40 0.60 0.80 1.00
relative abundance
quartz
silicates
mixtures
sulfates
carbonaceous
other
Fig. 2: Relative abundance of particle classes as function of altitude over Tinfou, Morocco
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