An integrated framework of coastal flood modelling under the failures of sea dikes: a case study in Shanghai

AbstractClimate change leads to sea level rise worldwide, as well as increases in the intensity and frequency of tropical cyclones (TCs). Storm surge induced by TC’s, together with spring tides, threatens to cause failure of flood defenses, resulting in massive flooding in low-lying coastal areas. However, limited research has been done on the combined effects of the increasing intensity of TCs and sea level rise on the characteristics of coastal flooding due to the failure of sea dikes. This paper investigates the spatial variation of coastal flooding due to the failure of sea dikes subject to past and future TC climatology and sea level rise, via a case study of a low-lying deltaic city- Shanghai, China. Using a hydrodynamic model and a spectral wave model, storm tide and wave parameters were calculated as input for an empirical model of overtopping discharge rate. The results show that the change of storm climatology together with relative sea level rise (RSLR) largely exacerbates the coastal hazard for Shanghai in the future, in which RSLR is likely to have a larger effect than the TC climatology change on future coastal flooding in Shanghai. In addition, the coastal flood hazard will increase to a large extent in terms of the flood water volume for each corresponding given return period. The approach developed in this paper can also be utilized to investigate future flood risk for other low-lying coastal regions.

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Long-Term Dynamic of Land Reclamation and Its Impact on Coastal Flooding: A Case Study in Xiamen, China

Land ◽

10.3390/land10080866 ◽

2021 ◽

Vol 10 (8) ◽

pp. 866

Author(s):

Lilai Xu ◽

Shengping Ding ◽

Vilas Nitivattananon ◽

Jianxiong Tang

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Land Reclamation ◽

Coastal Flooding ◽

Coastal Development ◽

Accurate Information ◽

Coastal Flood ◽

Flood Impact

While land reclaimed from the sea meets the land demand for coastal development, it simultaneously causes socio-economic systems to be prone to coastal flooding induced by storm surges and sea-level rise. Current studies have seldom linked reclamation with coastal flood impact assessment, hindering the provision of accurate information to support coastal flood risk management and adaptation. This study, using Xiamen, China as a case study, incorporates the spatiotemporal dynamics of reclamation into a coastal flood impact model, in order to investigate the long-term influence of reclamation activities on coastal flood inundation and the consequent exposure of the population to coastal flooding. We find that rapid population growth, continual economic development and urbanization drive a substantial logarithmic increase in coastal reclamation. Historical and future expansions of seaward land reclamation are found to cause dramatic surges in the expected annual inundation (EAI) and the expected annual population (EAP) exposed to coastal flooding. In Xiamen, EAI is estimated to increase by 440.2% from 1947 to 2035, owing to continuing land reclamation. Consequently, the population living in the flooded area has also increased sharply: the EAP of total population is estimated to rise from 0.8% in 1947 to 4.7% in 2035, where reclamation contributes over 80% of this increase. Moreover, a future 10 cm sea-level rise in 2035 will lead to extra 5.73% and 8.15% increases in EAI and EAP, respectively, and is expected to cause massive permanent submersion in the new reclamation zone. Our findings emphasize an integration of hard structures and nature-based solutions for building resilient coasts.

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Wave farm impacts on coastal flooding under sea-level rise: A case study in southern Spain

The Science of The Total Environment ◽

10.1016/j.scitotenv.2018.10.422 ◽

2019 ◽

Vol 653 ◽

pp. 1522-1531 ◽

Cited By ~ 14

Author(s):

Rafael J. Bergillos ◽

Cristobal Rodriguez-Delgado ◽

Gregorio Iglesias

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Coastal Flooding ◽

Southern Spain ◽

Wave Farm

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Building capacity on ecosystem-based adaptation strategy to cope with extreme events and sea-level rise on the Uruguayan coast

International Journal of Climate Change Strategies and Management ◽

10.1108/ijccsm-07-2017-0149 ◽

2018 ◽

Vol 10 (4) ◽

pp. 504-522 ◽

Cited By ~ 1

Author(s):

Inti Carro ◽

Leonardo Seijo ◽

Gustavo J. Nagy ◽

Ximena Lagos ◽

Ofelia Gutiérrez

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Coastal Management ◽

Native Species ◽

National Level ◽

River Estuary ◽

Extreme Weather Events ◽

Content Type ◽

And Sea Level

Purpose This study aims to show a case study of ecosystem-based adaptation (EbA) measures to increase coastal system’s resilience to extreme weather events and sea-level rise (SLR) implemented at Kiyú (Uruguayan coast of the Rio de la Plata river estuary). Design/methodology/approach A participatory process involving the community and institutional stakeholders was carried out to select and prioritise adaptation measures to reduce the erosion of sandy beaches, dunes and bluffs due to extreme wind storm surge and rainfall, SLR and mismanagement practices. The recovery of coastal ecosystems was implemented through soft measures (green infrastructure) such as revegetation with native species, dune regeneration, sustainable drainage systems and the reduction of use pressures. Findings Main achievements of this case study include capacity building of municipal staff and stakeholders, knowledge exchanges with national-level decision makers and scientists and the incorporation of EbA approaches by subnational-level coastal governments. To consolidate EbA, the local government introduced innovations in the coastal management institutional structure. Originality/value The outcomes of the article include, besides the increase in the resilience of social-ecological systems, the strengthening of socio-institutional behaviour, structure and sustainability. This experience provides insights for developing a strategy for both Integrated Coastal Management and climate adaptation at the national scale.

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Using adaptation tipping points to prepare for climate change and sea level rise: a case study in the Netherlands

Wiley Interdisciplinary Reviews Climate Change ◽

10.1002/wcc.64 ◽

2010 ◽

Vol 1 (5) ◽

pp. 729-740 ◽

Cited By ~ 165

Author(s):

Jaap C. J. Kwadijk ◽

Marjolijn Haasnoot ◽

Jan P. M. Mulder ◽

Marco M. C. Hoogvliet ◽

Ad B. M. Jeuken ◽

...

Keyword(s):

Climate Change ◽

The Netherlands ◽

Sea Level Rise ◽

Sea Level ◽

Tipping Points ◽

And Sea Level

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Coastal Flooding in the Maldives Induced by Mean Sea-Level Rise and Wind-Waves: From Global to Local Coastal Modelling

Frontiers in Marine Science ◽

10.3389/fmars.2021.665672 ◽

2021 ◽

Vol 8 ◽

Author(s):

Angel Amores ◽

Marta Marcos ◽

Rodrigo Pedreros ◽

Gonéri Le Cozannet ◽

Sophie Lecacheux ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Large Scale ◽

Land Reclamation ◽

Flood Hazard ◽

Wind Waves ◽

Coastal Flooding ◽

Major Drawback ◽

Mean Sea Level

The Maldives, with one of the lowest average land elevations above present-day mean sea level, is among the world regions that will be the most impacted by mean sea-level rise and marine extreme events induced by climate change. Yet, the lack of regional and local information on marine drivers is a major drawback that coastal decision-makers face to anticipate the impacts of climate change along the Maldivian coastlines. In this study we focus on wind-waves, the main driver of extremes causing coastal flooding in the region. We dynamically downscale large-scale fields from global wave models, providing a valuable source of climate information along the coastlines with spatial resolution down to 500 m. This dataset serves to characterise the wave climate around the Maldives, with applications in regional development and land reclamation, and is also an essential input for local flood hazard modelling. We illustrate this with a case study of HA Hoarafushi, an atoll island where local topo-bathymetry is available. This island is exposed to the highest incoming waves in the archipelago and recently saw development of an airport island on its reef via land reclamation. Regional waves are propagated toward the shoreline using a phase-resolving model and coastal inundation is simulated under different mean sea-level rise conditions of up to 1 m above present-day mean sea level. The results are represented as risk maps with different hazard levels gathering inundation depth and speed, providing a clear evidence of the impacts of the sea level rise combined with extreme wave events.

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Applying principles of uncertainty within coastal hazard assessments to better support coastal adaptation

10.26686/wgtn.14349251.v1 ◽

2021 ◽

Author(s):

SA Stephens ◽

RG Bell ◽

Judith Lawrence

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Flood Hazard ◽

Coastal Flooding ◽

Coastal Hazards ◽

Time Range ◽

Coastal Hazard ◽

Adaptive Planning ◽

Groundwater Levels ◽

Hazard Assessments

© 2017 by the authors. Coastal hazards result from erosion of the shore, or flooding of low-elevation land when storm surges combine with high tides and/or large waves. Future sea-level rise will greatly increase the frequency and depth of coastal flooding and will exacerbate erosion and raise groundwater levels, forcing vulnerable communities to adapt. Communities, local councils and infrastructure operators will need to decide when and how to adapt. The process of decision making using adaptive pathways approaches, is now being applied internationally to plan for adaptation over time by anticipating tipping points in the future when planning objectives are no longer being met. This process requires risk and uncertainty considerations to be transparent in the scenarios used in adaptive planning. We outline a framework for uncertainty identification and management within coastal hazard assessments. The framework provides a logical flow from the land use situation, to the related level of uncertainty as determined by the situation, to which hazard scenarios to model, to the complexity level of hazard modeling required, and to the possible decision type. Traditionally, coastal flood hazard maps show inundated areas only. We present enhanced maps of flooding depth and frequency which clearly show the degree of hazard exposure, where that exposure occurs, and how the exposure changes with sea-level rise, to better inform adaptive planning processes. The new uncertainty framework and mapping techniques can better inform identification of trigger points for adaptation pathways planning and their expected time range, compared to traditional coastal flooding hazard assessments.

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Flood hazard assessment from storm tides, rain and sea level rise for a tidal river estuary

Natural Hazards ◽

10.1007/s11069-018-3251-x ◽

2018 ◽

Vol 102 (2) ◽

pp. 729-757 ◽

Cited By ~ 6

Author(s):

P. M. Orton ◽

F. R. Conticello ◽

F. Cioffi ◽

T. M. Hall ◽

N. Georgas ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Hazard Assessment ◽

Flood Hazard ◽

River Estuary ◽

Tidal River ◽

Flood Hazard Assessment ◽

And Sea Level

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New Structural Technology Solution to Overcome Sea Dikes Construction and Operation Problems Responding to Climate Change and Sea-Level Rise in Vietnam

10.1007/978-981-16-7160-9_129 ◽

2021 ◽

pp. 1269-1279

Author(s):

Ngoc Nguyen Van ◽

Binh Bui Quoc ◽

Quoc Hoan Pham

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Technology Solution ◽

Sea Dikes ◽

And Sea Level

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Developments in large-scale coastal flood hazard mapping

10.5194/nhess-2016-124 ◽

2016 ◽

Cited By ~ 2

Author(s):

Michalis I. Vousdoukas ◽

Evangelos Voukouvalas ◽

Lorenzo Mentaschi ◽

Francesco Dottori ◽

Alessio Giardino ◽

...

Keyword(s):

Large Scale ◽

Flood Hazard ◽

Coastal Flooding ◽

Water Volume ◽

Hazard Mapping ◽

Population Exposure ◽

Storm Event ◽

Volume Discharge ◽

Computational Costs ◽

Coastal Flood

Abstract. Coastal flooding related to marine extreme events has severe socio-economic impacts, and even though the latter are projected to increase under the changing climate, there is a clear deficit of information and predictive capacity related to coastal flood mapping. The present contribution reports on efforts towards a new methodology for mapping coastal flood hazard at European scale, combining (i) the contribution of waves to the total water level; (ii) improved inundation modelling; and (iii) an open, physics-based framework which can be constantly upgraded, whenever new and more accurate data become available. Four inundation approaches of gradually increasing complexity and computational costs were evaluated in terms of their applicability for large-scale coastal flooding mapping: static inundation (SM); a semi-dynamic method, considering the water volume discharge over the dykes (VD); the Flood Intensity Index approach (Iw); and the model LISFLOOD-FP (LFP). A validation test performed against observed flood extents during the Xynthia storm event showed that SM and VD can lead to an overestimation of flood extents by 232% and 209 %, while Iw and LFP showed satisfactory predictive skill. Application at pan-European scale for the present-day 100-year event confirmed that static approaches can overestimate flood extents by 56 % compared to LFP; however, Iw can deliver results of reasonable accuracy in cases when reduced computational costs are a priority. Moreover, omitting the wave contribution in the extreme TWL can result in a ~ 60 % underestimation of the flooded area. The present findings have implications for impact assessment studies, since combination of the estimated inundation maps with population exposure maps revealed differences in the estimated number of people affect within the 20–70 % range.

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