a Sharafti - PhD Candidate, Water Engineer (Civil Eng), Iran University Science of Technology
b Zahabiyoun - Assistant Professor, Water Engineer (Civil Eng), Iran University Science of Technology

The existence of random variables is the major reason for uncertainty in flood modeling. One of the major random variables that can affect the shape of flood hydrographs is storm pattern among others. Storm pattern include duration, depth and time distribution for any event producing its corresponding flood event. Therefore, uncertainty analysis of flood modeling depends on uncertainty analyses of those effective variables of storm pattern. In this paper, a methodology was developed and used for identification and evaluation of significant variables affecting a storm pattern. Moreover, random properties of storm pattern are evaluated. The study catchment chosen for this analysis is called Seymareh, located in the western part of Iran. Having compared sharpness indices simulated with respective of observed storms, it was shown that storms of small rainfall depth as well as lengthy duration happen with less uncertainty.

Uncertainty analysis, Storm pattern, Seymareh catchment