Document Type : Research Paper
Quality of rainfall information for a given watershed or region is primary information needed for the sustainable designing and operation of water resources systems. For an optimal rainfall network design, they should be reviewed periodically based on the information needs and future water resources development plans. This study evaluated regional values of raingages in great Karoun basin located in Khozestan , Iran, using the discrete entropy. Discrete entropy can overcome limits of data normality assumption in past research and applications for hydrological variables. To determine the regional value of each station within a region, several information parameters such as marginal entropy, joint entropy and transinformation index between stations, were calculated to identify essential raingauge and critical area. Sensitivity analysis to number of discrete intervals showed that the entropy is sensitive to changes, but the ranks based on entropy indices appear to be less sensitive. Finally, results confirm that the entropy is useful to characterize the essential and excess station in the region and density of 31 raingauge network is optimal and other raingauge can be removed from monitoring network.