Open AccessBIVARIATE FLOOD FREQUENCY ANALYSIS USING GUMBEL COPULA
Author(s) -
Tarmizi Ismail,
Kamal Ahmed,
Mahiuddin Alamgir,
Mohammad Noor Kakar,
Abu Bakar Fadzil
Publication year - 2018
Publication title -
malaysian journal of civil engineering
Language(s) - English
Resource type - Journals
ISSN - 1823-7843
DOI - 10.11113/mjce.v30n2.474
Subject(s) - gumbel distribution , copula (linguistics) , bivariate analysis , weibull distribution , joint probability distribution , statistics , flood myth , return period , generalized pareto distribution , mathematics , univariate , cumulative distribution function , econometrics , multivariate statistics , extreme value theory , geography , probability density function , archaeology
A copula based methodology is presented in this study for bivariate flood frequency analysis over a station over a Kelantan river basin located in Northeast Malaysia. The joint dependence structures of three flood characteristics, namely, peak flow, flood volume and flood duration were modelled using Gumble Copula. Various univariate distribution functions of flood variables were fitted with observed flood variables to find the best distributions (eg. generalized pareto, log-normal, exponential, gamma distribution, weibull, gumbel, cauchy). The results of study revealed that different variable fits with different distributions and the correlation analysis among variables showed a strong association. Cumulative joint distribution functions (CDF) of peakflow and volume, peakflow and duration and volume and duration revealed that return period of joint return periods are much higher.