Conservation Choices in the Face of Sea-Level Rise: A Case Study on Marsh Migration from Phippsburg, Maine

Abstract Rising sea levels and growing coastal populations are intensifying interactions at the land-sea interface. To stabilize upland and protect human developments from coastal hazards, landowners commonly emplace hard armoring structures, such as bulkheads and revetments, along estuarine shorelines. The ecological and economic consequences of shoreline armoring have garnered significant attention; however, few studies have examined the extent of hard armoring or identified drivers of hard armoring patterns at the individual landowner level across large geographical areas. This study addresses this knowledge gap by using a fine-scale census of hard armoring along the entire Georgia U.S. estuarine coastline. We develop a parsimonious statistical model that accurately predicts the probability of armoring emplacement at the parcel level based on a set of environmental and socioeconomic variables. Several interacting influences contribute to patterns of shoreline armoring; in particular, shoreline slope and the presence of armoring on a neighboring parcel are strong predictors of armoring. The model also suggests that continued sea level rise and coastal population growth could trigger future increases in armoring, emphasizing the importance of considering dynamic patterns of armoring when evaluating the potential effects of sea level rise. For example, evolving distributions of armoring should be considered in predictions of future salt marsh migration. The modeling approach developed in this study is adaptable to assessing patterns of hard armoring in other regions. With improved understanding of hard armoring distributions, sea level rise response plans can be fully informed to design more efficient scenarios for both urban development and coastal ecosystems.

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Mapping the soft and ethical dimensions of sea level rise in southern Sweden

10.5194/egusphere-egu2020-21324 ◽

2020 ◽

Author(s):

Lisa Van Well ◽

Anette Björlin ◽

Per Danielsson ◽

Godefroid Godefroid Ndayikengurukiye ◽

Gunnel Göransson

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Coastal Areas ◽

Ecological Impacts ◽

Gis Mapping ◽

Ethical Values ◽

Southern Sweden ◽

Sea Levels ◽

Rising Sea Levels

Sea level rise poses profound challenges within current municipal and regional governance since it requires unusually long planning horizons, is surrounded by great uncertainties, and gives rise to novel ethical challenges. Adaptation to climate change is fundamentally an ethical issue because the aim of any proposed adaptation measure is to protect that which is valued in society. One of the most salient ethical issues discussed in the adaptation literature relates to the distribution of climate related risks, vulnerabilities and benefits across populations and over time. Raising sea-walls is typically associated with high costs and potentially negative ecological impacts as well as substantial equity concerns; managed retreat or realignment often causes problems related to property rights; and migration out of low-lying areas can involve the loss of sense and cultural identity and impact on receiving communities.How can the soft and ethical dimensions of rising mean sea levels be characterized and how can their consequences be mapped? To help municipalities to understand the values and ethics attached to measures to deal with long-term rising sea levels in southern Sweden, we are developing a methodology of soft or ethical values to complement to GIS-mapping of coastal vulnerability based on coastal characteristics and socio-economic factors.Rather than determining these values a priori, they are being discerned through workshops with relevant stakeholders and in interviews with citizens residing in and utilizing the coastal areas. The methodology attempts to determine the place-based of values within coastal communities with a focus on &#8220;whose&#8221; values, &#8220;what&#8221; values, and the long-term or short-term nature of values. It builds on an analytical framework developed to acquire information on the behavior, knowledge, perception and feelings of people living, working and enjoying the coastal areas. &#160;In turn this stakeholder-based information is used to co-create &#8220;story maps&#8221; as tools to communicate complicated vulnerability analyses, highlight the ethical dimensions of various adaptation measures, raise awareness and aid decisionmakers in taking uncomfortable decisions to &#8220;wicked&#8221; planning problems around the negative effects of sea level rise, coastal erosion and urban flooding.This paper presents the methodological development of the task as well as the results the study in four Swedish municipalities. The representation of the &#8220;soft&#8221; and ethical values provides an opportunity to help clarify these values to policymakers and increase resilience to rising sea levels.

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Rising Sea Levels Bring a Tidal Change to Tourism

Eos ◽

10.1029/2021eo157200 ◽

2021 ◽

Vol 102 ◽

Author(s):

Richard Sima

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Sea Levels ◽

Rising Sea Levels ◽

Tidal Change

A series of industry posters reimagines iconic locales in light of sea level rise and issues a call for action against climate change.

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Extending Urban Development on Water: Jakarta Case Study

Environment and Urbanization Asia ◽

10.1177/0975425320938539 ◽

2020 ◽

Vol 11 (2) ◽

pp. 247-265

Author(s):

Rukuh Setiadi ◽

Joerg Baumeister ◽

Paul Burton ◽

Johanna Nalau

Keyword(s):

Climate Change ◽

Urban Development ◽

Sea Level ◽

National Level ◽

Sea Levels ◽

Coastal Cities ◽

Metropolitan Cities ◽

Development Trajectory ◽

Rising Sea Levels

This article introduces the concept of ‘Sea Cities’ to emphasize a range of tactics to acknowledge the relationship between the sea and cities. This concept is critical for the possibility of integrating future aquatic-based urbanism to address climate change, and in particular, the issue of rising sea levels, which is currently faced by the majority of coastal cities. We compare and assess the tactics of four sea cities (i.e., to fortify, accommodate, release, and floating) against the case study of Jakarta. Jakarta is deemed to be among the metropolitan cities most vulnerable to sea level rise, owing to overpopulation alongside the fact that its land is sinking rapidly due to massive urban development. In order to understand the prospects and pitfalls of each tactic for Jakarta, we analyse scholarly literature on the subject, official government reports and documents, as well as policy briefs released by governments at the national level. This study finds that massive hard structural solutions are not only insufficient but also ineffective towards solving the challenges of climate change in Jakarta, especially the rising sea level. At the same time, it also identifies that while the combination of accommodating and floating tactics has never been considered as future a planning option, this could enable more resilient and adaptive solutions for the future development trajectory of Jakarta. In doing so, it could also provide important transferrable lessons for other coastal cities, especially those within developing countries.

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Sea-Level Reconstructions and Archaeological Indicators: A Case Study from the Submerged Hellenistic Harbor at Akko, Israel

10.5194/egusphere-egu21-2376 ◽

2021 ◽

Author(s):

Alyssa Victoria Pietraszek ◽

Oded Katz ◽

Jacob Sharvit ◽

Beverly Goodman-Tchernov

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Sea Level Change ◽

Relative Sea Level ◽

Factors Affecting ◽

Sea Levels ◽

Level Change ◽

Structural Deterioration ◽

Short And Long Term

With the impending threat of continued sea-level rise and coastal inundation, it is important to understand the short- and long-term factors affecting sea-level in a particular region. Such a feat can be accomplished by turning to indicators of past sea-levels. This study aims to highlight the utility of archaeological indicators in sea-level reconstructions, using Akko on Israel&#8217;s northern Mediterranean micro-tidal coast as a case study. Here, installations belonging to the maritime metropolis&#8217; Hellenistic Period (3rd to 1st centuries BCE) harbor, which have well-constrained chronological and elevational limitations, were identified at depths averaging 1.1 to 1.2 meters below present sea-level (mbpsl). These features would have been located sub-aerially during the time of their construction and use, indicating a change in relative sea-level in the area since this time. Utilizing a multiple proxy approach incorporating marine sedimentological and geoarchaeological methodologies with previously recorded regional data, three possible explanations for this apparent sea-level change were assessed: structural deterioration, sea-level rise, and vertical tectonic movements. This study revealed that, although signs of structural deterioration are apparent in some parts of the quay, this particular harbor installation is well-established as in situ as it has a continuous upper surface and its southern edge is built directly on the underlying bedrock. Consequently, the harbor&#8217;s current submarine position can instead be attributed to sea-level change and/or vertical tectonic displacements. While this amount of sea-level rise (over 1 m) is in agreement with glacio-hydro-eustatic values suggested for other areas of the Mediterranean, it falls below those previously reported locally. In addition, most studies suggest that the tectonic movement along this stretch of coastline is negligible. These new data provide a reliable relative sea-level marker with very little error with regard to maximum sea-level, thereby renewing the overall consideration of the tectonic and sea-level processes that have been active along this stretch of coastline during the last 2,500 years.

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Multi-Criteria Decision Analysis of Coastal Inundation at Regional scale

10.5194/egusphere-egu21-6963 ◽

2021 ◽

Author(s):

Vinay Shivamurthy ◽

Bharath Aithal

Keyword(s):

High Risk ◽

Decision Analysis ◽

Sea Level Rise ◽

Sea Level ◽

Natural Hazards ◽

Flood Risk ◽

Sea Levels ◽

Risk Levels ◽

Multi Criteria Decision Analysis ◽

Rising Sea Levels

Coastal flooding are natural processes that are both i) essential (providing nutrients to the coastal vegetation, habitats) and ii) hazardous (negatively impact human activities, livelihood, assets, livestock and so on). Climate changes have induced higher frequency of floods, rising sea levels, high amplitude tides and other climatic extremes at regional to global scales. The increasing intensity, duration of floods is proportionately increasing the risks associated with coastal human habitations. The regional risks are defined based on the physical, demographic, socio-economic vulnerability of the habitants. Sea level rise would further enhance the coastal inundations permanently breaching these productive, densely populated regions. This necessitates the need for spatially assessing the relative hazard, vulnerability and risks at regional scales to reduce/mitigate risks.Indian subcontinent supports the second largest global population, with numerous megacities, towns and villages along the coast and mainland. This study's main objective is to quantify the risk associated with inundations caused by rising sea levels, tidal surge at the regional level. As a case study, Sagar Island located in the verge of Sundarbans, south of West Bengal is considered. Flood risk assessment in the island has been carried out using Multi-Criteria Decision Analysis (MCDA) framework based on 23 spatial parameters.Results indicate, within a century (1922 &#8211; 2020), the island has lost most of its natural vegetation (mangroves - Sundarbans) (47% to 3%), with increasing cultivated (agriculture, horticulture) spaces (77.4 %) and built-up environs (8.2%). Sea level rise varies from 4.4 mm/year (South) to 5.25 mm/year (North) and in the last century has breached over 2824 hectares of mainland. The study's findings reveal 19.8% of horticulture and 33.3% of agriculture assets are highly exposed to natural hazards. 1.34% population are at relatively very high-risk levels, 17.81% at high-risk levels. The study's findings reveal the variable importance of socio-economic, demographic, topographic and proximity to public service, in defining the flood vulnerability and risk towards the habitants. The approach and findings of paves the way for planning authorities to prioritise risk mitigation strategies that are region-specific to reduce the impact of inundation due to natural hazardsKeywords: Sea level rise, Flood risk, MCDA, Vulnerability, flood hazard

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A National Study on Protecting Infrastructure and Public Buildings against Sea Level Rise and Storm Surge

10.20944/preprints202108.0214.v1 ◽

2021 ◽

Author(s):

Paul Chinowsky ◽

Jacob Helman

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Storm Surge ◽

The United States ◽

Design Guidelines ◽

National Study ◽

Multiple Perspectives ◽

Sea Levels ◽

Rising Sea Levels ◽

The Cost

The national study analyzes sea level rise (SLR) impacts based on 36 different SLR and storm surge scenarios across 5.7 million geographic locations and 3 time periods. Taking an approach based on engineering design guidelines and current cost estimates, the study details projected cost impacts for states, counties, and cities. These impacts are presented from multiple perspectives including total cost, cost per-capita, and cost per-square mile. The purpose of the study is to identify specific locations where infrastructure is vulnerable to rising sea levels. The study finds that Sea Level Rise (SLR) and minimal storm surge is a $400 billion threat to the United States by 2040 that includes a need for at least 50,000 miles of protective barriers. The research is limited in its scope to protecting coastal infrastructure with sea walls. Additional methods exist and may be appropriate in individual situations. The study is original in that it is a national effort to identify infrastructure that is vulnerable as well as the cost associated with protecting this infrastructure.

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Resilience in the Face of Sea Level Rise: An Architectural Response to Rising Sea Levels in Wellington, New Zealand

10.26686/wgtn.17007925.v1 ◽

2021 ◽

Author(s):

◽

Michael Barrington Hatch

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Global Climate ◽

Research Question ◽

Capital City ◽

Direct Result ◽

Sea Levels ◽

Coastal City ◽

The Face

Climate change is widely regarded as the leading global issue of the 21st century. There is now a general international agreement, supported by an overwhelming amount of scientific evidence, that the global climate is changing at an accelerated rate and that human-driven emissions of greenhouse gases into the atmosphere is the main factor driving this trend. Arguably the most devastating impact of climate change on the human civilisation will be a rapidly increasing rise in global sea levels, which are currently rising at an unprecedented rate, placing hundreds of millions of people at serious risk of inundation in coastal communities across the globe. In the case of New Zealand’s capital city, Wellington, over ten percent of the city’s residents are at risk of displacement by the end of this century. This thesis aims to find a solution to resident displacement in the coastal city, addressing the question, How can a resilient residential dwelling be designed for the coastal city, in response to the encroaching pressures of climate change driven sea level rise? This research question and its subsequent design aims have been achieved through a highly iterative design process resulting the development of a connected network of amphibious dwelling solutions which provide the residents of the selected focus community of Kilbirnie, a coastal suburb in Wellington city, with the capacity to accommodate, adapt and thrive in the face of sea inundation. Hereby ensuring the social sustainability of the coastal community, currently at serious risk of displacement as a direct result of climate change driven sea level rise.

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Resilience in the Face of Sea Level Rise: An Architectural Response to Rising Sea Levels in Wellington, New Zealand

10.26686/wgtn.17007925 ◽

2021 ◽

Author(s):

◽

Michael Barrington Hatch

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Global Climate ◽

Research Question ◽

Capital City ◽

Direct Result ◽

Sea Levels ◽

Coastal City ◽

The Face

Climate change is widely regarded as the leading global issue of the 21st century. There is now a general international agreement, supported by an overwhelming amount of scientific evidence, that the global climate is changing at an accelerated rate and that human-driven emissions of greenhouse gases into the atmosphere is the main factor driving this trend. Arguably the most devastating impact of climate change on the human civilisation will be a rapidly increasing rise in global sea levels, which are currently rising at an unprecedented rate, placing hundreds of millions of people at serious risk of inundation in coastal communities across the globe. In the case of New Zealand’s capital city, Wellington, over ten percent of the city’s residents are at risk of displacement by the end of this century. This thesis aims to find a solution to resident displacement in the coastal city, addressing the question, How can a resilient residential dwelling be designed for the coastal city, in response to the encroaching pressures of climate change driven sea level rise? This research question and its subsequent design aims have been achieved through a highly iterative design process resulting the development of a connected network of amphibious dwelling solutions which provide the residents of the selected focus community of Kilbirnie, a coastal suburb in Wellington city, with the capacity to accommodate, adapt and thrive in the face of sea inundation. Hereby ensuring the social sustainability of the coastal community, currently at serious risk of displacement as a direct result of climate change driven sea level rise.

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Numerical Modeling of Saltwater Intrusion in the Rmel-Oulad Ogbane Coastal Aquifer (Larache, Morocco) in the Climate Change and Sea-Level Rise Context (2040)

Water ◽

10.3390/w13162167 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2167

Author(s):

Mohamed Jalal EL Hamidi ◽

Abdelkader Larabi ◽

Mohamed Faouzi

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Coastal Aquifer ◽

Fresh Groundwater ◽

Sea Levels ◽

Groundwater Levels ◽

Rising Sea Levels ◽

Management Approaches ◽

And Sea Level

Many coastal aquifers have experienced seawater intrusion (SWI) into fresh groundwater aquifers. The principal causes of SWI include over-pumping and events such as climate change (CC) and rising sea levels. In northern Morocco, the Rmel-Oulad Ogbane coastal aquifer (ROOCA) supplies high-quality groundwater for drinking water and agriculture. This favorable situation has led to increased pumping, resulting in environmental challenges such as dropping water table and SWI. Furthermore, the climate has resulted in less recharge, with an estimated annual precipitation of 602 mm and an average temperature of 18.5 °C. The goal of this study is to determine how CC, over-pumping, and sea-level rise (SLR) affect SWI. Computational groundwater and solute transport models are used to simulate the spatial and temporal evolution of hydraulic heads and groundwater solute concentrations. The calibration is based on steady and transient groundwater levels from 1962 to 2040. SWI simulations show that the NW sector of the coastal area would be polluted, with the toe reaching 5.2 km inland with a significant salinity (15–25 g/L). To protect the fresh water in the reservoir from SWI, enhanced groundwater development and management approaches for this aquifer are required, such as artificial recharge from surface water.

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