Developing a Mathematical Model to Estimate the Intensity of the Global Radiation

This research aimed to create an empirical\udmathematical model to estimate the average monthly of total\uddaily radiation of the global radiation in the middle of northeast\udThailand. The model showed the ratio of the monthly average of\uddaily radiation on the radiation outside the Earth's atmosphere\udwhich contains cloud index: n, ozone: l, perceptible water: w,\udand visibility: VIS, where: the value of n came from the data\udfrom meteorological satellites MTSAT-2, the value of l came\udfrom the data from AURA satellite, the value of w was\udcalculated from temperature and humidity of the air, and the\udvalue of VIS came from the measurements from meteorological\udstations. For testing the performance of the model, the\udresearchers calculated the average monthly of total daily\udradiation intensity at Maha Sarakham, Roi Et, Khon Kaen and\udKalasin provincial meteorological stations. Then, the results\udwere compared with the measured values. The comparison\udshowed that the results from the calculation and measurement\udare consistent in the good standing. The Root Mean Square\udDifference value (RMSD) of the monthly average of total daily\udradiation intensity was between 5.25 to 13.82%. On the other\udhand, the Mean Bias Difference value (MBD) was negative\udwithin the range of -0.99 to -13.47%