Physical Sciences and Mathematics Commons^™

A Bayesian Hierarchical Approach To Multivariate Nonstationary Hydrologic Frequency Analysis, C. Bracken, K. D. Holman, B. Rajagopalan, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

We present a general Bayesian hierarchical framework for conducting nonstationary frequency analysis of multiple hydrologic variables. In this, annual maxima from each variable are assumed to follow a generalized extreme value (GEV) distribution in which the location parameter is allowed to vary in time. A Gaussian elliptical copula is used to model the joint distribution of all variables. We demonstrate the utility of this framework with a joint frequency analysis model of annual peak snow water equivalent (SWE), annual peak flow, and annual peak reservoir elevation at Taylor Park dam in Colorado, USA. Indices of largescale climate drivers—El Ni~no Southern …