Kipp&Zonen BSRN Scientific Solar Monitoring System - Manual (Page 132)

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Figure C 2.3. Measured sky functions and their approxim ations by ones
calculated for m odel atm osphere containing rural aerosol and haze particles.
Diffusometer Diffuse radiation
from 0.5
0
Circum 1
0.5 – 1.0
0 0
Circum 2
l
1.0 - Z 0
“Measured”
value
Australia I 160 -3.11 -8.47 148.4
Australia II 160 -3.11 -8.51 148.4
Austria 160 -3.11 -16.90 140.0
Germ any I 160 -3.11 -15.96 141.0
Germ any II 160 -3.11 -9.90 147.0
Germ any III 160 -3.11 -8.46 148.3
Hungary I 160 -3.11 -8.53 148.4
Hungary II 160 -3.11 -10.41 146.5
Hungary III 160 -3.11 -11.92 145.8
USA 160 -3.11 -10.03 146.9
Table C 2.2a. Diffusom eter irradiances in W m . -2
The radiation coming from the solar disk and from the belt up to 0.5 degree around it is excluded. The
l
circumsolar radiance is divided into two parts. Z means the limit angle of the diffusometer.
C 2.3 The measurement method
Between March of 1996 and August of 1997 three diffusom eter of shading sphere were operated in
Budapest using a SciTec solar tracker. Their characteristics are shown in Table C 2.1. The sam pling
of outputs were m ade at each 10 seconds, the stored data are 10 m inutes averages. Due to different
reasons, the operation was not continuous during the 18 m onths period, this way only the 60 percent
of the possible daytim e 10 m inutes averages are available (cc. 33000 “readings”). The tim e series
contain every kind of atm ospheric conditions and solar elevation (up to 66 degrees) happened in that
period. The data were processed in the year 2000 only.