استنباط نموذجين رياضيين لتخمين الاشعاع الشمسي الكلي الساقط على السطح الافقي في مدينة الموصل

The results of global solar radiation falling on horizontal surface in Mosul city for the time series (1980-2005) were studied and analyzed. Gaussian model represents the normal distribution of monthly means for daily data as a function of months number of year only was found with local constants. This model gives a high accuracy in applying, where the correlation coefficient between measured and estimated values was (R=0.996). New two mathematical models also found in this study to estimate global solar radiation on plane surface. The first one as a function of relative humidity and cloudiness. The second as a function of difference between maximum and minimum temperatures, cloudiness and relative humidity. The Performance of both were very high and (M.A.E) not accessed 2.53%, 1.40% respectively. The correlation coefficient values that we obtained between measured and estimated data was (R=0.997) for the first model and (R=0.998) for the second one.