Further data on solar radiation in Shiraz, Iran

Instantaneous solar radiation data read from the chart of global solar radiation on a horizontal surface as well as sun shine hours in Shiraz during the 1991–1993 period are analysed and compared with solar conditions in the 1970s and 80s. It is apparent from the recorded data and the consequent analysis of the statistics that, while the city of Shiraz possesses a relatively high abundance of sunshine with clear sky index conditions, there is a gradual decay in the values of instantaneous solar radiation and its maximum.