Temporal-spatial investigation of net short wavelength solar radiation using FLDAS global model data in Iran

In order to use solar energy optimally, the first step is to identify the amount of solar radiation. It is useful to use satellite data to identify the amount of solar radiation in any situation. Therefore, the aim of the current study is to investigate the time-space amount of net short wavelength solar radiation in Iran. Then, in order to check the time of the data on a monthly and seasonal scale, their graphs were drawn, and linear and polynomial regression were used to determine trends. In order to carry out this research, monthly radiation energy data in nc format was prepared from the FLDAS satellite model for the years 1982 to 2021. The result of the long-term linear trend shows that Iran has a stable trend to some extent, but its non-linear trend shows several alternating upward and downward periods. Also, for the spatial analysis of the radiation spread in Iran, zoning was done in the Arc Gis environment. The results showed that the maximum amount of radiant energy in June is 296 watts per square meter and the lowest amount is 101 watts per square meter in December. The highest coefficient of change occurred in January (6.69%) and the lowest in September (1.47%). Therefore, Iran has the same