In Fig. 8 the RAH tab is shown. In this screen the user obtainsthe parameters of extraterrestrial radiation (Rah), solar radiationwith clear sky (Rso) and equivalent evaporation (Eo), for shortperiods, hourly. They are calculated by using Eqs. (5), (13) and respectively. These data are calculated only if the user previ-ously entered the position data needed in GPS tab. The tool permitsto click on the figures plotted in this tab in order to know how theparameters obtained are related to the arrows plotted. For exam-ple, in Fig. 8, the user has selected the arrow that corresponds tothe extraterrestrial solar radiation. The parameters computation for a day-to-day period is not available in this version, but it will beenabled in a near future.