EM 1110-2-1100 (Part II)
30 Apr 02
Figure II-5-26.
Example phasing of storm surge and tide (Jarvinen and Gebert 1986)
(2) Historical method.
(a) There are two basic approaches to the use of historical data for generating recurrence interval
relationships. The first is the graphical method, the second makes use of analytical formulas to describe the
behavior of the frequency relationship.
(b) The graphical method involves construction of a cumulative probability density function (or
probability distribution function) in which the magnitude of the event is plotted against percent probability
of exceedance.
(c) In addition to the graphical approach of developing a pdf, a variety of analytical methods exist for
estimating these functions. Selection of a specific form depends on the behavior of the historical data and
the purpose of the study. One function, the Pearson Type III distribution, is presented in detail in USACE
II-5-46
Water Levels and Long Waves
Previous Page
