Recent measurements of broad-band turbidity parameters in the island of Cyprus

In the present analysis broad-band turbidity coefficients, which depend upon the attenuation over the entire solar spectrum, are presented. These coefficients are determined from unfiltered pyrheliometric observations of normal incidence direct solar irradiance. Thus, the Linke turbidity factor TL and the Unsworth-Monteith attenuation coefficient TUM were calculated from pyrheliometric cloudless-sky observations at Athalassa, Cyprus, for the period 1985 to 1992. It was shown that the minima of turbidity levels occur during the winter (January) and maxima during spring (May). A Linke turbidity factor “derived” from hourly pyranometric observations is presented. Finally, the rural climate of Athalassa, Cyprus, proved to have lower turbidity levels than several other sites representing semi-rural, urban-polluted and desert climates, respectively.