Most of the phenomena which are analyzed and lie in different branches of engineering and science have a random nature. Thus, we cannot judge about their occurrence or their precise behavior in the favorite time strictly. Nevertheless, by using statistical and probabilistic methods, it became possible to extract some rules about the phenomena's probability and some relevant indexes (e.g. average values) due to their past behavior and other effective factors. In the current project, by using extreme value analysis of the wave data which obtained from the Persian Gulf waves hindcast and prepared by Baird Company, the designing waves for the return periods of 10, 25, 50, 100 years in the project selected areas has been calculated.
A sample of extreme analysis accomplished around the third phase of monitoring and modeling studies of Boushehr coastal areas