Generation of Rainfall Intensity Duration Curves Using Disaggregation Technique

Abstract

The rainfall intensity-duration-frequency (IDF) relationship is a relationship between rainfall duration, rainfall intensity and storm return period generally required for outlining of various hydraulic structures such as dams, Culverts, Siphons etc. Evaluation of rainfall extreme expected values, as used in intensityduration-frequency (IDF) relationship, has long been a major interest of both theoretical and applied studies in surface hydrology. The IDF relationship is resolved through factual investigation of tests of records from a given meteorological stations cover the study region. For the present study, information from the verifiable arrangement of most extreme month to month precipitation acquired from a pluviometric Kirkuk station were utilized. They were made accessible by the Ministry of Water Resources. Thirty seven outrageous occasions were gotten from the record from years of 1971 to 2010. Considering that the sample is representative of the genesis of the intense rainfalls of the studied region and that the probability of the events follows distribution of extremes Type I (Gumbel distribution). Many stations do not have long information records for lengths shorter than 1 day and in this way the character of short precipitation lengths must be evaluated from different sources. The fundamental focus point of this paper is to build IDF curves for the area utilizing precipitation recurrence investigation procedures utilizing new disaggregation strategy method. Different durations ranging from 5 minutes to 24 hours for return periods of 5, 10, 50, and 100 years were analyzed