Abstract
In the hydrologic design of water management infrastructures, rainfall characteristics are often used and the available historical rainfall events in the form of intensity-duration-frequency (IDF) curves are essential. However, due to the rise in the emission of greenhouse gases, the magnitude and frequency of future extreme rainfalls will be changed. Therefore, the current study aims to develop the IDF curves models in the region of Makkah Al Mukarramah, Saudi Arabia. In this study, five models were developed to estimate the rainfall intensity for the different durations and return periods, using three statistical parameters e, m, and C, calculated from the rainfall intensity data for the time series in each station. The results showed that the rainfall intensity average is ranged between 15.4 mm/10 min and 25.9 mm/60 min for Al Karr Sufli station from 1966 to 2005, and 29.8 mm/120 min and 49.6 mm/720 min for Baqrane station during the period of 1971-2005. Besides, the KGE, R-2, and Theil's U performance tests of the probability distribution models revealed that the exponential model is the best for the Al-Barzah, Ain Al Azizia and Al Karr Sufli, and Humma Syssed stations, and the log Pearson III model is the best model for Baqrane station. The outcomes of this research reveal the potential of this approach in projecting upcoming climate situations for urban catchment where long-term hourly rainfall data are not easily available.