Use of a nonstationary copula to predict future bivariate low flow frequency in the Connecticut river basin

TitleUse of a nonstationary copula to predict future bivariate low flow frequency in the Connecticut river basin
Publication TypeJournal Article
Year of Publication2016
AuthorsAhn, Kuk-Hyun, and Palmer Richard N.
JournalHydrological Processes
Volume30
Issue19
Pagination3518 - 3532
Date PublishedJune-12-2017
Keywordsfrequency analysis, Hydrology, stream flow
Abstract

Frequency analysis of streamflow provides an essential ingredient in our understanding of hydrologic events and provides needed guidance in the design and management of water resources infrastructure. However, traditional hydrologic approaches often fail to include important external effects that can result in unpredictable or unforeseen changes in streamflow. Moreover, previous studies investigating multiple characteristics of streamflow do not address a nonstationary approach. This study explores nonstationary frequency analysis of bivariate characteristics, including occurrence and severity, of annual low flow in the Connecticut River Basin, United States. To investigate bivariate low flow frequency, copulas and their marginal distributions are constructed by using stationary and nonstationary approaches. Our study results indicate that streamflow used in this study demonstrate significant nonstationarity. Over time, the occurrence and severity of low flows are shown to be lower with the same probability based on the results of nonstationary copulas. Bivariate low flow frequencies in the years 1970, 2000, and 2030, and their joint return periods are estimated under the nonstationary copulas. Copyright © 2016 John Wiley & Sons, Ltd.

URLhttp://onlinelibrary.wiley.com/doi/10.1002/hyp.10876/abstract
DOI10.1002/hyp.10876
Short TitleHydrol. Process.