Refining Surface Net Radiation Estimates in Arid and Semi-arid Climates of Iran

This study investigates the accuracy of the ISCCP FD and AIRS surface air and skin temperatures, as well as the ISCCP FD and MODIS surface albedos and aerosol optical depths. The comparisons showed that the AIRS air and skin temperatures were slightly more accurate compared to the surface measurements than those in ISCCP FD. The MODIS surface albedos differed from the ISCCP FD values by no more than 0.02–0.07, but because these differences are mostly at longer wavelengths, they did not change the net solar radiation very much. Therefore, to obtain the best estimate of surface net radiation with the best combination of spatial and temporal resolution, we developed a method to adjust the ISCCP FD surface longwave fluxes using the AIRS surface air and skin temperatures to obtain the higher spatial resolution of the latter, while retaining the 3-hr time intervals of the former.