Regional flood dynamics in a bifurcating mega delta simulated in a global river model

Dai Yamazaki, Tomoko Sato, Shinjiro Kanae, Yukiko Hirabayashi, Paul D. Bates

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

In this paper we show the importance of bifurcation channels for flow in river mega deltas through the use of a new computational scheme implemented in the global hydrodynamic model, CaMa-Flood (Catchment-based Macro-scale Floodplain model). First, we developed a new river network map based on SRTM3 DEM (Shuttle Radar Topography Mission 3 arc-second Digital Elevation Model) and HydroSHEDS (hydrological data and maps based on shuttle elevation derivatives at multiple scales) which includes bifurcation channels. Next, we implemented a new bifurcation scheme in CaMa-Flood capable of routing flow along this network and used the model to simulate the Mekong River. We show that in the Mekong delta such channels route about 50% of total flow and that their representation is essential for realistic hydrodynamic simulations. A simulation without bifurcation channels was obviously unrealistic because no flow occurred between the mainstem and adjacent channels even when their water level difference was >6m. The bifurcation channels are extracted from globally available data sets; thus, it is straightforward to expand the proposed scheme to global-scale studies. Key Points Automatic delineation of bifurcation channels in a global river network map A new channel bifurcation flow scheme in a global hydrodynamic model Simulation with bifurcation flow shows reasonable agreement to observations

Original languageEnglish
Pages (from-to)3127-3135
Number of pages9
JournalGeophysical Research Letters
Volume41
Issue number9
DOIs
Publication statusPublished - 2014 May 16
Externally publishedYes

Fingerprint

bifurcation
rivers
river
hydrodynamics
scale models
digital elevation model
floodplain
catchment
simulation
digital elevation models
Shuttle Radar Topography Mission
delineation
routing
radar
topography
water level
arcs
routes
water

Keywords

  • delta
  • global modeling
  • hydrodynamics

ASJC Scopus subject areas

  • Earth and Planetary Sciences(all)
  • Geophysics

Cite this

Regional flood dynamics in a bifurcating mega delta simulated in a global river model. / Yamazaki, Dai; Sato, Tomoko; Kanae, Shinjiro; Hirabayashi, Yukiko; Bates, Paul D.

In: Geophysical Research Letters, Vol. 41, No. 9, 16.05.2014, p. 3127-3135.

Research output: Contribution to journalArticle

Yamazaki, Dai ; Sato, Tomoko ; Kanae, Shinjiro ; Hirabayashi, Yukiko ; Bates, Paul D. / Regional flood dynamics in a bifurcating mega delta simulated in a global river model. In: Geophysical Research Letters. 2014 ; Vol. 41, No. 9. pp. 3127-3135.
@article{e79049c4f48346f0ba2e4673f90082b8,
title = "Regional flood dynamics in a bifurcating mega delta simulated in a global river model",
abstract = "In this paper we show the importance of bifurcation channels for flow in river mega deltas through the use of a new computational scheme implemented in the global hydrodynamic model, CaMa-Flood (Catchment-based Macro-scale Floodplain model). First, we developed a new river network map based on SRTM3 DEM (Shuttle Radar Topography Mission 3 arc-second Digital Elevation Model) and HydroSHEDS (hydrological data and maps based on shuttle elevation derivatives at multiple scales) which includes bifurcation channels. Next, we implemented a new bifurcation scheme in CaMa-Flood capable of routing flow along this network and used the model to simulate the Mekong River. We show that in the Mekong delta such channels route about 50{\%} of total flow and that their representation is essential for realistic hydrodynamic simulations. A simulation without bifurcation channels was obviously unrealistic because no flow occurred between the mainstem and adjacent channels even when their water level difference was >6m. The bifurcation channels are extracted from globally available data sets; thus, it is straightforward to expand the proposed scheme to global-scale studies. Key Points Automatic delineation of bifurcation channels in a global river network map A new channel bifurcation flow scheme in a global hydrodynamic model Simulation with bifurcation flow shows reasonable agreement to observations",
keywords = "delta, global modeling, hydrodynamics",
author = "Dai Yamazaki and Tomoko Sato and Shinjiro Kanae and Yukiko Hirabayashi and Bates, {Paul D.}",
year = "2014",
month = "5",
day = "16",
doi = "10.1002/2014GL059744",
language = "English",
volume = "41",
pages = "3127--3135",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "9",

}

TY - JOUR

T1 - Regional flood dynamics in a bifurcating mega delta simulated in a global river model

AU - Yamazaki, Dai

AU - Sato, Tomoko

AU - Kanae, Shinjiro

AU - Hirabayashi, Yukiko

AU - Bates, Paul D.

PY - 2014/5/16

Y1 - 2014/5/16

N2 - In this paper we show the importance of bifurcation channels for flow in river mega deltas through the use of a new computational scheme implemented in the global hydrodynamic model, CaMa-Flood (Catchment-based Macro-scale Floodplain model). First, we developed a new river network map based on SRTM3 DEM (Shuttle Radar Topography Mission 3 arc-second Digital Elevation Model) and HydroSHEDS (hydrological data and maps based on shuttle elevation derivatives at multiple scales) which includes bifurcation channels. Next, we implemented a new bifurcation scheme in CaMa-Flood capable of routing flow along this network and used the model to simulate the Mekong River. We show that in the Mekong delta such channels route about 50% of total flow and that their representation is essential for realistic hydrodynamic simulations. A simulation without bifurcation channels was obviously unrealistic because no flow occurred between the mainstem and adjacent channels even when their water level difference was >6m. The bifurcation channels are extracted from globally available data sets; thus, it is straightforward to expand the proposed scheme to global-scale studies. Key Points Automatic delineation of bifurcation channels in a global river network map A new channel bifurcation flow scheme in a global hydrodynamic model Simulation with bifurcation flow shows reasonable agreement to observations

AB - In this paper we show the importance of bifurcation channels for flow in river mega deltas through the use of a new computational scheme implemented in the global hydrodynamic model, CaMa-Flood (Catchment-based Macro-scale Floodplain model). First, we developed a new river network map based on SRTM3 DEM (Shuttle Radar Topography Mission 3 arc-second Digital Elevation Model) and HydroSHEDS (hydrological data and maps based on shuttle elevation derivatives at multiple scales) which includes bifurcation channels. Next, we implemented a new bifurcation scheme in CaMa-Flood capable of routing flow along this network and used the model to simulate the Mekong River. We show that in the Mekong delta such channels route about 50% of total flow and that their representation is essential for realistic hydrodynamic simulations. A simulation without bifurcation channels was obviously unrealistic because no flow occurred between the mainstem and adjacent channels even when their water level difference was >6m. The bifurcation channels are extracted from globally available data sets; thus, it is straightforward to expand the proposed scheme to global-scale studies. Key Points Automatic delineation of bifurcation channels in a global river network map A new channel bifurcation flow scheme in a global hydrodynamic model Simulation with bifurcation flow shows reasonable agreement to observations

KW - delta

KW - global modeling

KW - hydrodynamics

UR - http://www.scopus.com/inward/record.url?scp=84901947958&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84901947958&partnerID=8YFLogxK

U2 - 10.1002/2014GL059744

DO - 10.1002/2014GL059744

M3 - Article

VL - 41

SP - 3127

EP - 3135

JO - Geophysical Research Letters

JF - Geophysical Research Letters

SN - 0094-8276

IS - 9

ER -