Publication
Title
Mangroves as nature-based mitigation for ENSO-driven compound flood risks in a large river delta
Author
Abstract
Densely populated coastal river deltas are very vulnerable to compound flood risks coming from both oceanic and riverine sources. Climate change may increase these compound flood risks due to sea level rise and intensifying precipitation events. Here, we investigate to what extent nature-based flood defence strategies, through the conservation of mangroves in a tropical river delta, can contribute to mitigate the oceanic and riverine components of compound flood risks. While current knowledge of estuarine compound flood risks is mostly focussed on short-term events such as storm surges (taking 1 or a few days), longer-term events, such as El Niño events (continuing for several weeks to months) along the Pacific coast of Latin America, are less studied. Here, we present a hydrodynamic modelling study of a large river delta in Ecuador aiming to elucidate the compound effects of El Niño-driven oceanic and riverine forcing on extreme high water level propagation through the delta and, in particular, the role of mangroves in reducing the compound high water levels. Our results show that the deltaic high water level anomalies are predominantly driven by the oceanic forcing but that the riverine forcing causes the anomalies to amplify upstream. Furthermore, mangroves in the delta attenuate part of the oceanic contribution to the high water level anomalies, with the attenuating effect increasing in the landward direction, while mangroves have a negligible effect on the riverine component. These findings show that mangrove conservation and restoration programmes can contribute to nature-based mitigation, especially the oceanic component of compound flood risks in a tropical river delta.
Language
English
Source (journal)
Hydrology and earth system sciences. - Katlenburg-Lindau
Publication
Katlenburg-Lindau : 2024
ISSN
1027-5606
1607-7938
DOI
10.5194/HESS-28-1463-2024
Volume/pages
28 :6 (2024) , p. 1463-1476
ISI
001194949400001
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Project info
Effects of El Niño and mangrove deforestation on extreme high water level dynamics in a tropical delta.
Tidal marshes: bio-geomorphic self-organization and its implications for resilience to sea level rise and changing sediment supply (TIGER).
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Record
Identifier
Creation 03.04.2024
Last edited 06.05.2024
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