Global Changes in 20‐Year, 50‐Year, and 100‐Year River Floods

Abstract Concepts like the 100‐year flood event can be misleading if they are not updated to reflect significant changes over time. Here, we model observed annual maximum daily streamflow using a nonstationary approach to provide the first global picture of changes in: (a) the magnitudes of the 20‐,...

Full description

Saved in:
Bibliographic Details
Main Authors: L. Slater, G. Villarini, S. Archfield, D. Faulkner, R. Lamb, A. Khouakhi, J. Yin
Format: Article
Language:English
Published: Wiley 2021-03-01
Series:Geophysical Research Letters
Subjects:
Online Access:https://doi.org/10.1029/2020GL091824
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850281601878982656
author L. Slater
G. Villarini
S. Archfield
D. Faulkner
R. Lamb
A. Khouakhi
J. Yin
author_facet L. Slater
G. Villarini
S. Archfield
D. Faulkner
R. Lamb
A. Khouakhi
J. Yin
author_sort L. Slater
collection DOAJ
description Abstract Concepts like the 100‐year flood event can be misleading if they are not updated to reflect significant changes over time. Here, we model observed annual maximum daily streamflow using a nonstationary approach to provide the first global picture of changes in: (a) the magnitudes of the 20‐, 50‐, and 100‐year floods (i.e., flows of a given exceedance probability in each year); (b) the return periods of the 20‐, 50‐, and 100‐year floods, as assessed in 1970 (i.e., flows of a fixed magnitude); and (c) corresponding flood probabilities. Empirically, we find the 20‐/50‐year floods have mostly increased in temperate climate zones, but decreased in arid, tropical, polar, and cold zones. In contrast, 100‐year floods have mostly decreased in arid/temperate zones and exhibit mixed trends in cold zones, but results are influenced by the small number of stations with long records, and highlight the need for continued updating of hazard assessments.
format Article
id doaj-art-8fc062a00098466d9d60af7096d4812a
institution OA Journals
issn 0094-8276
1944-8007
language English
publishDate 2021-03-01
publisher Wiley
record_format Article
series Geophysical Research Letters
spelling doaj-art-8fc062a00098466d9d60af7096d4812a2025-08-20T01:48:15ZengWileyGeophysical Research Letters0094-82761944-80072021-03-01486n/an/a10.1029/2020GL091824Global Changes in 20‐Year, 50‐Year, and 100‐Year River FloodsL. Slater0G. Villarini1S. Archfield2D. Faulkner3R. Lamb4A. Khouakhi5J. Yin6School of Geography and the Environment University of Oxford Oxford UKIIHR ‐ Hydroscience & Engineering University of Iowa Iowa City IA USAU.S. Geological Survey Reston VA USAJBA Consulting Skipton UKJBA Trust Skipton UKSchool of Water, Energy and Environment Center for Environmental and Agricultural Informatics Cranfield University Cranfield UKState Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan ChinaAbstract Concepts like the 100‐year flood event can be misleading if they are not updated to reflect significant changes over time. Here, we model observed annual maximum daily streamflow using a nonstationary approach to provide the first global picture of changes in: (a) the magnitudes of the 20‐, 50‐, and 100‐year floods (i.e., flows of a given exceedance probability in each year); (b) the return periods of the 20‐, 50‐, and 100‐year floods, as assessed in 1970 (i.e., flows of a fixed magnitude); and (c) corresponding flood probabilities. Empirically, we find the 20‐/50‐year floods have mostly increased in temperate climate zones, but decreased in arid, tropical, polar, and cold zones. In contrast, 100‐year floods have mostly decreased in arid/temperate zones and exhibit mixed trends in cold zones, but results are influenced by the small number of stations with long records, and highlight the need for continued updating of hazard assessments.https://doi.org/10.1029/2020GL091824floodsglobalhazardnonstationarityprobabilitiesreturn periods
spellingShingle L. Slater
G. Villarini
S. Archfield
D. Faulkner
R. Lamb
A. Khouakhi
J. Yin
Global Changes in 20‐Year, 50‐Year, and 100‐Year River Floods
Geophysical Research Letters
floods
global
hazard
nonstationarity
probabilities
return periods
title Global Changes in 20‐Year, 50‐Year, and 100‐Year River Floods
title_full Global Changes in 20‐Year, 50‐Year, and 100‐Year River Floods
title_fullStr Global Changes in 20‐Year, 50‐Year, and 100‐Year River Floods
title_full_unstemmed Global Changes in 20‐Year, 50‐Year, and 100‐Year River Floods
title_short Global Changes in 20‐Year, 50‐Year, and 100‐Year River Floods
title_sort global changes in 20 year 50 year and 100 year river floods
topic floods
global
hazard
nonstationarity
probabilities
return periods
url https://doi.org/10.1029/2020GL091824
work_keys_str_mv AT lslater globalchangesin20year50yearand100yearriverfloods
AT gvillarini globalchangesin20year50yearand100yearriverfloods
AT sarchfield globalchangesin20year50yearand100yearriverfloods
AT dfaulkner globalchangesin20year50yearand100yearriverfloods
AT rlamb globalchangesin20year50yearand100yearriverfloods
AT akhouakhi globalchangesin20year50yearand100yearriverfloods
AT jyin globalchangesin20year50yearand100yearriverfloods