Quantifying and Predicting the Contribution of Sea-Level Rise to Shoreline Change in Ghana: Information for Coastal Adaptation Strategies

2017 ◽  
Vol 336 ◽  
pp. 1283-1291 ◽  
Author(s):  
Prosper I.K. Evadzi ◽  
Eduardo Zorita, ◽  
Birgit Hünicke
Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1220 ◽  
Author(s):  
Luis Maria Abadie ◽  
Elisa Sainz de Murieta ◽  
Ibon Galarraga

Iberian coastal cities are subject to significant risks in the next decades due to climate change-induced sea-level rise. These risks are quite uncertain depending on several factors. In this article, we estimate potential economic damage in 62 Iberian coastal cities from 2020 to 2100 using regional relative sea-level rise data under three representative concentration pathways (RCP 8.5, RCP 4.5 and RCP 2.6). We analyze the expected accumulated damage costs if no adaptation actions take place and compare this scenario to the investment cost of some adaptation strategies being implemented. The results show that some adaptation strategies are less costly than the potential damage under inaction. In other words, it is economically rational to invest in adaptation even in a context of high uncertainty. These calculations are very relevant to inform climate change adaptation decisions and to better manage the risk posed by sea-level rise. Moreover, our findings show the importance of a good understanding of the shape of the sea-level rise and damage cost distributions to calculate the expected damage. We show that using the 50th percentile for these calculations is not adequate as it leads to a serious underestimation of expected damage and coastal risk.


2021 ◽  
Vol 9 (9) ◽  
pp. 974
Author(s):  
Maurizio D’Anna ◽  
Deborah Idier ◽  
Bruno Castelle ◽  
Sean Vitousek ◽  
Goneri Le Cozannet

Long-term (>decades) coastal recession due to sea-level rise (SLR) has been estimated using the Bruun Rule for nearly six decades. Equilibrium-based shoreline models have been shown to skillfully predict short-term wave-driven shoreline change on time scales of hours to decades. Both the Bruun Rule and equilibrium shoreline models rely on the equilibrium beach theory, which states that the beach profile shape equilibrates with its local wave and sea-level conditions. Integrating these two models into a unified framework can improve our understanding and predictive skill of future shoreline behavior. However, given that both models account for wave action, but over different time scales, a critical re-examination of the SLR-driven recession process is needed. We present a novel physical interpretation of the beach response to sea-level rise, identifying two main contributing processes: passive flooding and increased wave-driven erosion efficiency. Using this new concept, we analyze the integration of SLR-driven recession into equilibrium shoreline models and, with an idealized test case, show that the physical mechanisms underpinning the Bruun Rule are explicitly described within our integrated model. Finally, we discuss the possible advantages of integrating SLR-driven recession models within equilibrium-based models with dynamic feedbacks and the broader implications for coupling with hybrid shoreline models.


2021 ◽  
Author(s):  
◽  
Georgina Hart

<p>The Earth's climate system is entering a period of dynamic change after millennia of relatively stable climate. Coastal communities will need to adapt to dynamically shifting coastal environments as the climate system changes and sea levels rise. This study adds to a growing literature that investigates coastal vulnerability, adaptation, and resilience to climate change. It investigates regional scale social and institutional barriers to adaptation to sea level rise; examines the exposure, sensitivity and adaptation options at two coastal settlements in the Auckland region – Mission Bay/Kohimarama and Kawakawa Bay; and it analyses coastal adaptation response options from a resilience perspective. Mission Bay/Kohimarama and Kawakawa Bay, Auckland will experience increasing coastal hazard risk as the numbers of people and property potentially affected by storm events increases as sea level rises. Findings from the present study suggest that existing settlements in the Auckland region may already be 'locked in' to a coastal adaptation approach focused on maintaining the current coastline through coastal stabilisation, an approach that will decrease community resilience and increase vulnerability in the long term, even if this is found to be a successful response in the short term. Retreat offers an alternative approach that is strongly aligned with reducing community vulnerability and increasing resilience; however, strong opposition from communities to any retreat approach is expected. Developing trusted climate science information, education around coastal hazard risk, and participatory community led decision-making are identified as central enablers for a retreat approach to be included as a viable coastal adaptation option for communities in the Auckland region.</p>


2020 ◽  
Author(s):  
Rosanne Martyr-Koller ◽  
Tabea Lissner ◽  
Carl-Friedrich Schleussner

&lt;p&gt;Climate impacts increase with higher warming and evidence is mounting that impacts increase strongly above 1.5&amp;#176;C. Therefore, adaptation needs also rise substantially at higher warming levels. Further&lt;strong&gt;, &lt;/strong&gt;limits to adaptation will be reached above 1.5&amp;#176;C and loss and damage will be inferred. Coastal Nature-based Solutions (NbS) have arisen as popular adaptation options, particularly for coastal developing economies and Small Island Developing States (SIDS), because of their lower overall costs compared to traditional grey infrastructure approaches such as seawalls and levees; their economic co-benefits through positive effects on sectors such as tourism and fisheries; and a broader desire to shift toward so-called blue economies. Two NbS of particular interest for coastal protection are: 1) coral reefs, which reduce coastal erosion and flooding through wave attenuation; and 2) mangroves, which provide protection from storms, tsunamis and coastal erosion. Although there is international enthusiasm to implement these solutions, there is limited understanding of the future viability of these ecosystems, particularly in their capacities as coastal adaptation service providers, in a warmer world.&lt;/p&gt;&lt;p&gt;In this presentation, we highlight how long and with how much coverage coral and mangrove ecosystems can provide coastal protection services for future climate scenarios, using air temperature and sea level rise as climate change indicators. A mathematical model for each ecosystem is developed, based on the physical parameters necessary for the sustainability of these ecosystems. We investigate the protective capabilities of each ecosystem under warming and sea level rise scenarios compatible with: below 1.5&amp;#176;C warming; below 2&amp;#176;C warming; warming based on current global commitments to carbon emissions reductions (3-3.5&amp;#176;C); and with no carbon mitigation (6&amp;#176;C). Results show what temperature and sea level rise values beyond which these ecosystems can no longer provide coastal protective services. These results have also been framed in a temporal window to show when these services may not be feasible, beyond which more costly adaptation measures and/or loss and damage may be incurred.&lt;/p&gt;


Sign in / Sign up

Export Citation Format

Share Document