Comparison between measured global irradiance at the ground surface and estimated extraterrestrial irradiance over Zarqa City-Jordon

الملخص EN

In this study, the comparison between estimated extraterrestrial irradiance and the measured global irradiance using GS1 Solarimeter is presented for Zarqa city/Jordan (Latitude 32.2N Longitude 36.35E) for the period from 1st November 2001 to 31st September 2002.

Solar radiation attenuation in Zarqa city is estimated by comparing the measured and the calculated extraterrestrial irradiances.

The clearness index was found not to be above than 0.8 for the clear days.

In an attempt to study the relation between the global radiation attenuation and some metrological variables, a power equation which relates the clearness index to the daily temperature range was obtained.

Also, the linear regression of the clearness index and daily maximum temperature (measured in oC) for the total period of observation was obtained.