Ultraviolet solar radiation at Dhahran, Saudi Arabia

UV and global solar radiation in Łódź, Central Poland

“…The local atmospheric conditions result in the variability between sites. For example, in Valencia the ratio varied from 2.9 to 3.5% (Martinez-Lozano et al, 1999), in Dhahran (Saudi Arabia) from 2.1% on dusty days to 4.6% on rainy days (Elhadidy et al, 1990), in Potsdam with overcast sky the ratios varied between 5 and 6%, whereas on cloudless days they did not exceed 4.5% (Feister and Grasnick, 1992).…”

“…The greater absorption of UV than global irradiance during high optical air mass could have been caused by the presence of SO 2 and dustiness in the polluted urban atmosphere. The increase of the relative contribution of UV in global solar irradiation at time of low solar elevation, up to 4.9%, could result from the fact that the absorption by water vapor in the near infra-red part of the spectrum was stronger than for shorter wavelengths (Elhadidy et al, 1990;MartinezLozano et al, 1999). Ratios (Ruv/g) varied little for solar elevations over 40°: 3.5 to 4.3% (Table IV).…”

Spatio-Temporal Characteristics in the Clearness Index Derived from Global Solar Radiation Observations in Korea

“…While these extinction processes are complex, the estimation of sky conditions using incident solar radiation at a given location has been proposed as a simple approach. The ratio of the global solar radiation measured at the surface to the extraterrestrial solar radiation is defined as the clearness index (K T ) [4][5][6][7][8]. The clearness index has been used as a general indicator of the combined effects of the various extinction processes, which determine the transmission of solar radiation through the atmosphere.…”

Impact of Cloud Cover on Global UV Irradiance over Baghdad, Iraq

“…Solar UV radiation is usually divided into three bands UV-C (100-280 nm) which is completely absorbed by stratospheric ozone; UV-B (280-315 nm) which is only partially absorbed or scattered in the atmosphere and UV-A (315-400 nm) which makes up most of the UV radiation received at the earth's surface [1][2][3][4][5][6][7][8]. In outer space, UV-B and UV-A band represent only 7.45% of the total solar radiation [9].…”

“…A slight decrease in the stratospheric ozone leads to an increase in the UV-B reaching the earth. UV radiation data are of particular interest because such radiation is energetic enough to break apart several biological molecules, including DNA [4]. The increase in UV radiation affects human health [10].…”