197 results
Search Results
2. Early Holocene inundation of Doggerland and its impact on hunter-gatherers: An inundation model and dates-as-data approach.
- Author
-
Hoebe, P.W., Cohen, K.M., Busschers, F.S., van Heteren, S., and Peeters, J.H.M.
- Subjects
- *
FLOODS , *HOLOCENE Epoch , *ABSOLUTE sea level change , *EROSION , *HUNTER-gatherer societies , *SEA level - Abstract
Sea-level rise was a key factor changing environments during the Early Holocene in Northwest Europe. It affected Mesolithic hunter-gatherer communities by inundating large areas in the current North Sea, commonly referred to as Doggerland. In this paper we present novel inundation models for the southern North Sea providing visualisations of lateral inundation driven by sea-level rise and relate it to frequency analysis of radiocarbon dates from archaeological sites. These improve on previous studies that relied on bathymetric data, which includes post-inundation overprints of Holocene sedimentation and erosion, and thus significantly underestimates the timing of inundation in some areas. We constructed a paleoDEM (a composite elevation grid of the top of the Pleistocene) for the eastern part of the southern North Sea; and sea level surfaces that combine relative sea-level curves from glacio-isostatic adjustment models optimised for Britain and southern Scandinavia respectively. We corrected our paleoDEMs for tectonic background basin subsidence, and in the inundation modelling account for pre-compaction elevation of peat in coastal areas. We evaluated the impact of these model components on our results and describe the possible inundation history of Doggerland. We suggest earlier inundation than predicted by previous models, showing significant area loss around 10.5–10 ka cal BP. Palaeogeographic changes are compared with archaeological radiocarbon data using a dates-as-data approach. Composite Kernel Density Estimate and permutation tested Summed Probability Distributions are used as a proxy for the visibility, nature and intensity of human activity. Results indicate key periods of growth and decline recorded in the dataset, as well as regional differences in growth rate, some correlating with inundation phases. Chiefly, we find elevated growth rates around 10.5–10 ka in northwest Germany and the Netherlands, contemporaneous with the abovementioned phase of extensive area loss, and moreover, with changes in culture and practices on Early Mesolithic sites. However, the spatiotemporal distribution of archaeological data is significantly influenced by accessibility and preservation of sediments of a certain age. We discuss the importance of inundation modelling and sediment data in understanding how landscape taphonomy affects archaeological patterning, especially in dates-as-data approaches. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Regional implementation of coastal erosion hazard zones for archaeological applications.
- Author
-
Jones, Benjamin D., Collings, Ben, Dickson, Mark E., Ford, Murray, Hikuroa, Daniel, Bickler, Simon H., and Ryan, Emma
- Subjects
- *
COASTAL changes , *MAORI (New Zealand people) , *ABSOLUTE sea level change , *SEA level , *ARCHAEOLOGICAL excavations , *HAZARDS - Abstract
• Hazard zone methodology: The paper employs a hazard zone methodology, typically used for managing erosion risk to modern infrastructure, to assess and manage the risk to coastal archaeological heritage. • Coastal archaeological heritage at risk: Coastal archaeological heritage in Aotearoa/New Zealand is under threat from coastal erosion, with accelerated risk due to rising sea levels. • Projected sea-level rise impact: The study predicts that a relatively modest 20 cm of sea-level rise, expected by 2040, may put around 8 % (155) of coastal archaeological sites at risk, and a more significant 1 m of sea-level rise could threaten approximately 19 % (356) of sites. • Connection to indigenous communities: The coastal archaeological heritage is closely tied to Māori, the indigenous ancestral communities of Aotearoa/New Zealand. • Adaptive planning pathways: Scenarios are presented to assist stakeholders in assessing heritage risk, providing an opportunity for coastal managers to incorporate heritage considerations into adaptive planning pathways. Coastal archaeological heritage is in danger of being lost to coastal erosion, the risk of which is amplified by accelerating sea-level rise (SLR). In Aotearoa/New Zealand, coastal archaeological heritage is closely associated with indigenous ancestral communities, but our understanding of the spatiotemporal variability in coastal erosion risk for cultural heritage is limited. Coastal erosion hazard zones have typically been implemented to manage erosion risk to modern infrastructure at regional scales. In this study, we applied a hazard zone methodology in the context of coastal archaeological heritage for a selected region of Aotearoa (Te Tai Tokerau/Northland). Historical coastal change analyses reveal that most beaches in the region have been stable or slightly accretionary over the past ∼80 years, but a reversal of this trend is likely under the projected SLR, which is expressed in the coastal erosion hazard zones. Our analyses indicate that ∼8 % (155) of coastal archaeological sites in Te Tai Tokerau/Northland may be at risk of erosion with a relatively modest 20 cm of SLR, which is expected for the region by 2040, and ∼19 % (356) of sites are threatened by 1 m of SLR. Scenarios are presented that should assist a broad range of stakeholders to assess heritage risk and provide an opportunity for coastal managers to include heritage within adaptive planning pathways. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. Emplaced climate imaginaries: The regional construction of climate futures on the German Wadden Sea Coast.
- Author
-
Döring, Martin, Walsh, Cormac, and Ratter, Beate
- Subjects
ABSOLUTE sea level change ,COASTS ,SEMI-structured interviews ,GROUNDED theory - Abstract
It is increasingly recognised that the perceptions and lived experiences of climate change are grounded in places. This paper brings together work on place and climate imaginaries to develop a situated and emplaced understanding of climate change futures. Empirically, the paper examines local climate imaginaries on the North Frisian Wadden Sea coast of Germany. The low-lying islands are vulnerable to anthropogenic sea-level rise and face an uncertain future. Based on 21 semi-structured interviews conducted with coastal dwellers, the study examines all interviews from a grounded theory perspective. A refined in-depth analysis of the language helps to reveal climate imaginaries and systematise the ways through which local climate futures are articulated, structured and constructed. The aim of the paper is threefold: to synthesise research undertaken on place and climate imaginaries, to empirically analyse emplaced climate imaginaries and to explore – though tentatively – their role in developing regionally grounded climate change adaptation. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
5. Cartographic analysis as spatial determinant for climate change adaptation in the Hunter River Estuary, Australia.
- Author
-
Perez Lopez, Irene, Carrasco, Sandra, and Mariscal Madrigal, Cesar
- Subjects
- *
CLIMATE change adaptation , *PHYSIOLOGICAL adaptation , *ESTUARIES , *ABSOLUTE sea level change , *CRITICAL thinking , *URBAN growth - Abstract
This paper explores the hydrological history of the Hunter River and Estuary (Newcastle, Australia), to identify pathways for incorporating climate-sensitive adaptation approaches into urban development and planning. The research method utilises mapping as a methodological discovery tools to visually articulate the correlation of pre-colonial hydrological landscapes, the transformation of the estuary over two centuries, the areas identified as at risk, and the opportunities for developing a climate-resilient estuary. This research aims to contribute to the redefinition of the discourse on the role of estuary planning for changing climate, focusing on four critical aspects: identify the impacts of urbanisation and industrialisation on ecosystems and its correlation with climate hazard at the estuary; visualise such transformations over time and space to identify critical spatial and climate factors threatening inhabitation; propose strategic spatial practices towards adaptation and resilience; and synthesising the options to foster reflective thinking and establish a correlation with novel policies, governance and practices. The study highlights that adopting new urbanism aligned with cultural and ecological principles can mitigate future climate impacts through re-naturalisation and urban adaptation to sea-level rise by focusing on proactive approaches to building resilient communities. This paper also acknowledges the need for site-specific adaptive design and planning strategies at multiple scales and governance levels. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Transformation and recognition: Planning just climate havens in New York State.
- Author
-
Morris, Erin, Cousins, Joshua J., and Feldpausch-Parker, Andrea
- Subjects
COMMUNITIES ,CITIES & towns ,ABSOLUTE sea level change ,FOOD security ,SEA level - Abstract
Climate change is altering the context of human mobility due to disasters such as sea-level rise, forest fires, and other extreme events. It is also changing how places plan and adapt to these chaotic events. In this paper we examine how climate destinations, or host communities, are preparing for potential climate related in-migration in their climate adaptation planning. While no place will be left untouched by climate change, a number of cities and communities across Upstate New York consider themselves "climate havens" due to their lower risk to many climate impacts, such as sea level rise, access to freshwater resources, and infrastructure to accommodate growth. Within this context, what does it mean to plan a just climate haven? What types of policy and planning might be needed? How are planners and practitioners framing adaptation approaches? Using Q-methodology, we reveal two dominant perspectives among planners and activists in Upstate New York on how to plan just climate havens. The first is a transformational view that looks to address the social, political, and economic drivers of vulnerability. The second is a recognition view that looks to address legal and legislative shortcomings in how to support climate migrants. Points of consensus on how to build just climate havens between the two groups include co-production and co-design, workforce development, food security, and safe and affordable housing. We suggest that these two perspectives frame justice in two distinct—but overlapping—ways and provide a shared basis on how to consider planning a just climate haven. • Two perspectives frame how to plan just climate havens: Transformation and Recognition. • Perspectives unite around workforce development, food security, housing, and co-produced solutions, and material gains. • Climate destinations in Central New York need to build capacity to plan and adapt to future climate scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
7. Stratigraphic evolution and sediment dispersal in a marine rift-basin: The case of the Lewis trough, Eastern Dampier sub-basin (Australia).
- Author
-
Fava, Luca, Tremblay, François, and Cutten, Sarah
- Subjects
- *
MARINE sediments , *SEQUENCE stratigraphy , *ABSOLUTE sea level change , *GEOMORPHOLOGY , *SEDIMENT analysis , *RIFTS (Geology) , *WATERSHEDS - Abstract
The understanding of the stratigraphic evolution of marine rift basins is important for both "pure" scientific and economic reasons. From a hydrocarbon exploration point of view the main goal is to develop tools to predict reservoir location, quality, and extent. Stratigraphic models try to do that, and only historical cases can be used to test those models. On the other hand, depositional model cannot precisely predict reservoir location as factors unique to the specific basin under analysis affect sediment distribution (basin physiography, type of flows, among others). This aspect can be assessed only on a case-by-case basis and can be used for initial hypothesis generation based on analogues. This paper shows a case history study based on the integration of well logs, and 3D seismic data across the Eastern Dampier sub-basin, Northwester Shelf of Australia. Advanced seismic interpretation techniques, calibrated to well data, enable the definition of a chrono-stratigraphic framework of the late syn-rift sequence (Late Jurassic) of the Lewis Trough, and the description of the sediment distribution through the interpretation of geomorphological features. During the Late Jurassic three different channel systems deliver sandstones to the deep-water part of the basin through multiple entry points. The timing of the sediment input seems to be linked to variation of sediment input as during that time relative sea-level was slowly rising. The location of the entry points is related to local physiography and defies any attempt of prediction based on general "rules." From a stratigraphic point view, the findings of the study support the idea that, in rift basin, mechanical subsidence is the primary control for accommodation space, with episodic pulses of extension followed by longer periods of tectonic quiescence. It is during these episodic movements along the basin's bounding faults that space for sedimentation is created. This interpretation is in striking contrast with the basic assumptions of the conventional sequence stratigraphy model. • Understanding the stratigraphic evolution of marine rift basins allows to predict reservoir location and extent. • The present paper analyzes the late syn-rift succession of the Lewis Trough to reconstruct the stratigraphic evolution of the basin infill. • Accommodation space in the Lewis Trough is primarily controlled by mechanical subsidence related to asymmetrical fault movement. • Turbiditic sedimentation occurs during sea-level rise, and it is related to an Increase in sediment supply. • IConventional sequence stratigraphic modeling cannot be applied to rift-basins. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
8. Thick temporalities of planned relocation in Fiji.
- Author
-
McMichael, Celia and Katonivualiku, Manasa
- Subjects
CLIMATE change ,PLACE attachment (Psychology) ,ABSOLUTE sea level change ,CLIMATOLOGY ,COASTAL changes - Abstract
This paper examines the temporalities of planned relocation in response to climatic and environmental changes in Fiji. It is based on fieldwork among seven low-lying coastal villages under threat from sea- level rise and where planned relocation has been implemented, initiated or anticipated. The paper highlights how residents of these villages make sense of different temporalities and timescale: climate impacts and adaptation are understood to disrupt personal and intergenerational histories of attachment to place; climatic and environmental changes – such as sea-level rise, coastal erosion and flooding – and relocation planning and implementation are central to contemporary everyday experience; and climate impacts and relocation extend into the future in uncertain ways, albeit informed by future-oriented scientific estimates and local experience and observation. This paper argues that these temporalities are experienced as 'thick time' in which the past, present and future of climate change and relocation are palpable in the everyday. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
9. Unraveling the sediment routing systems evolution of the south Pyrenean foreland basin during the lower to middle Paleogene period.
- Author
-
Juvany, Philémon, Garcés, Miguel, López-Blanco, Miguel, Valero, Luís, Amorós, Elisabet Beamud, Poyatos-Moré, Miquel, and Rius, Albert Martínez
- Subjects
- *
ROUTING systems , *PALEOGENE , *BENTHIC zone , *ABSOLUTE sea level change , *SEDIMENTS , *THRUST - Abstract
Orogenesis plays a crucial role in creating, modifying, and disrupting sediment routing fairways. Reconstructing past source to sink systems is a critical step to unravel the geological history, mandatory to disentangle tectonic and climatic forcings, and to understand the perturbations that affected the overall system. The Paleocene-Eocene period is a debated early stage of the early Pyrenean orogeny, characterized by the piggy-back style tectonic partitioning of sub-basins as the deformation front propagates towards the southern foreland. An important issue is to understand how sedimentary systems reacted and reorganized in response to this dynamic scenario. and whether the stratigraphic and sediment provenance results align with the envisioned scenario. In this paper we aim at contributing to the paleogeographic, sedimentologic and tectono-sedimentary evolution of the South-Pyrenean foreland basin by reviewing the chronostratigraphic framework of the basin infill in its south-central sector (the Ager sub-basin in the Serres Marginals thrust sheet). We built five new magnetostratigraphic sections, which together encompass most of the Paleogene record, aimed to best reconcile magnetostratigraphic data with the defined biostratigraphic framework of the region including marine Shallow Benthic Zones (SBZ biozones) and continental mammalian localities (MP levels). Detailed trends in subsidence show the development and evolution of the foreland depozones, from forebulge to foredeep and wedge-top setting, relative to the successive emplacement of the Montsec and Serres Marginals thrust sheets. A correlation with the eastern portion of the foreland basin (Lower-Middle Pedraforca and Cadí Thrust Sheets) and adjacent northern Graus-Tremp basin (Montsec Thrust Sheet) was feasible and seeks to contribute to the tectono-sedimentary evolution of the South-Pyrenean foreland in the light of a source to sink approach. Our proposal includes a new paleogeographic evolution of the area in a series of paleogeographic maps from Late Thanetian to Late Cuisian times. • A Tectonosedimentary and paleogeographic evolution of the South Pyrenean foreland from Palaeocene to Lutetian times. • Pyrenean sourced sedimentary systems were routed from the eastern Pyrenees on the upper thrust sheets at the Eocene period. • Post PETM sea-level rise at 55.5 My (Ilerdian marine flooding) contributed to a reorganization in the sediment routing systems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Prioritising local sea level rise adaptation pathways in Shenzhen and Hong Kong using cost-benefit analysis.
- Author
-
Wang, Xinwei, Li, Yangfan, and Zhang, Qian
- Subjects
COST benefit analysis ,SEA level ,PHYSIOLOGICAL adaptation ,CLIMATE change adaptation ,ABSOLUTE sea level change ,CITIES & towns - Abstract
Local governments face urgent challenges from sea-level rise (SLR), impacting coastal urban areas significantly. Despite a shared commitment to adapting to climate change and SLR-induced hazards, strategies for SLR adaptation vary significantly between cities, reflecting a spectrum of political, socio-economic, and cultural contexts. This paper examines potential SLR adaptation strategies in Shenzhen and Hong Kong, cities with different political and socio-economic frameworks, to understand the effectiveness of varied local adaptation pathways to meet adaptation objectives. Through an analysis of shoreline adaptation infrastructures, including natural shelters and hard defense structures, alongside historical coastal reclamation data from 1985 to 2020, we identify the most cost-effective adaptation pathway. Specifically, our cost-benefit analysis reveals that Shenzhen's "Hybrid management" pathway offers superior economic efficiency, increasing benefits by up to 63% for only a 7%–16% rise in protection costs. Conversely, Hong Kong's "Relative-risk Reduction" pathway shows less timely adaptation actions, indicating a need for more dynamic approaches. The findings highlight the pitfalls of overly rigid SLR adaptation strategies and the necessity for flexible, transition-capable adaptation pathways to better manage future uncertainties. Lessons learned from this study will enable refinement of local SLR adaptation pathway approaches and could significantly improve decision-making under uncertainty in other coastal cities based on investment perspective. • Integrate coastal structures and reclamation to explore SLR adaptation pathways. • Limited investments constrains the efficacy of nature-based adaptation strategies. • Prioritise adaptation options is critical to address uncertainty in SLR management. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
11. Architectural design concept and guidelines for floating structures for tackling sea level rise impacts on Abu-Qir.
- Author
-
El-Shihy, Ahmed A. and Ezquiaga, José M.
- Subjects
SEA level ,ARCHITECTURAL models ,COASTAL zone management ,INTEGRATED coastal zone management ,RECLAMATION of land ,ADAPTIVE reuse of buildings ,ABSOLUTE sea level change - Abstract
Previous studies indicate that floating structures developed through the last decades concluding that it's the most sustainable solution against sea level rise (SLR), preferring it to land reclamation approaches regarding sustainability, lifespan, and cost-effectiveness, that Egyptian researches seem to disregard. This paper guides architects and urban planners when designing floating structures by introducing new approach of floating community model and architectural design guidelines for floating structures for tackling SLR impacts on Abu-Qir. To illustrate such approach, this paper initially conducts analysis on Abu-Qir and coastal management solutions practiced as their properties provide the required knowledge for selecting the best mitigation solution for such area. Second, it conducts exploratory analysis to investigate floating structures as a more sustainable and long-term solution. Third, applying conclusions from previous sections of site analysis, mitigation solutions, and floating structures to define a floating community concept model for Abu-Qir. Findings support key arguments that traditional mitigation methods aren't sustainable or long-term solutions. Analysis demonstrate Abu-Qir Bay as the most vulnerable area to SLR. Although floating structures have demonstrated not to be the optimum solution in every case regarding cost-effectiveness and/or site suitability, however upon site analysis, it presents itself as the ideal solution for Abu-Qir bay. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
12. Identifying high potential locations for run-of-the-river hydroelectric power plants using GIS and digital elevation models.
- Author
-
Zaidi, Arjumand Z. and Khan, Majid
- Subjects
- *
HYDROELECTRIC power plants , *GEOGRAPHIC information systems , *COST effectiveness , *DIGITAL elevation models , *ABSOLUTE sea level change - Abstract
The recent global energy crisis has provoked a need to explore alternate energy sources including run-of-the-river hydropower projects. To derive maximum payback for a given investment, finding the most advantageous siting of power plants is imperative. If a selection of potential sites misses some of the apparently indistinct sites with significant power potential, there is a chance of acquiring only partial benefits out of these investments. A review of the existing methods for evaluating power potential of a river is discussed in this paper with their limitations along with a new proposed approach. The new approach can be used to evaluate different installation schemes along a river to assess run-of-the-river hydropower potentials using geospatial data techniques to select sites exhibiting higher total hydropower potential. The case study of Kunhar River, located in the northern part of Pakistan, presents the applicability of the approach. Open source Advanced Spaceborne Thermal Emission (ASTER)’s digital elevation model (DEM) and regional hydrologic gauged data are used for identifying the best locations for hydropower plants, demonstrating this approach is substantially more cost effective and robust compared to other field based assessment. Replicating the proposed approach for other locations is easy following the step-by-step method presented in this paper and giving consideration to the limitations described. This study may provide guidelines for the development of cost-effective and energy efficient hydropower projects. The use of this approach is most advantageous in the preliminary assessment phase of a project to narrow the scope of the detailed study focusing only on the higher potential sites. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
13. An investigation of coastal climate change risk assessment practice in Australia.
- Author
-
Tonmoy, Fahim Nawroz, Wainwright, David, Verdon-Kidd, Danielle C., and Rissik, David
- Subjects
CLIMATE change ,COASTAL ecosystem health ,ENVIRONMENTAL protection ,ENVIRONMENTAL policy ,ABSOLUTE sea level change - Abstract
Local government organisations in coastal Australia have historically commissioned studies aimed at understanding risks in their locality to future sea level rise as a starting point for developing adaptation strategies to climate change. Therefore, the success of the overall adaptation activities of local government are strongly influenced by the way those initial risk studies are scoped and conducted, and how the outputs of those studies underpin subsequent adaptation planning activities within the organization. Mainstreaming of adaptation planning activities within local government is critical in terms of getting stakeholder support and required resources for its implementation. This paper analyses a sample of these coastal risk assessment studies across seven states and territories in Australia, with an aim to critically investigate the current state of practice among coastal local governments. First, we develop a typology of studies that have been undertaken by or for practitioners to understand coastal climate change risks, and discuss the applicability of the studies within the policy-making context of local government. Second, we identify a set of sample studies from the ‘grey literature’ through a systematic process and investigate to what extent they adhere to best practice risk management guidelines and principles, such as ISO31000. Third, we interview stakeholders from top performing studies to identify how/if the risk studies helped their organization in progressing their adaptation planning. We find that there is a significant inconsistency among terminologies in the coastal climate change risk assessment unpublished literature as studies use “risk”, vulnerability” and “hazard” concepts interchangeably despite their separate objectives and aims. Most studies perform poorly in evaluating risk against broader organizational criteria. Subsequently, it is difficult to integrate the findings of such studies into a broader organizational risk register, limiting opportunities for identified coastal climate change risks to be integrated into councils’ long-term strategic decision making. Conversely, the follow up interviews of studies that performed well in scoping and consultation in our assessment demonstrate that these aspects were beneficial to stakeholders in terms of informing adaptation planning. Importantly, the findings presented in this paper confirm the need for a consistent risk assessment approach for local councils in the coastal zone to underpin successful adaptation planning. This is a critical issue, not only for Australia, but for local government organisations globally given that sea level rise is a projected threat for all populated coastal regions worldwide. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
14. The role of the Holocene transgression in the environmental changes of lagoons and marshes of the Mediterranean coast.
- Author
-
Blázquez, A.M., López-Belzunce, M., Rodríguez-Pérez, A.E., Guillem, J., Ferrer, C., Nieto, M., Torres, T., and Ortiz, J.E.
- Subjects
- *
HOLOCENE Epoch , *MARSHES , *LAGOONS , *ABSOLUTE sea level change , *WETLANDS , *FOSSIL foraminifera , *SALT marshes - Abstract
The aim of this paper is to evaluate the position of the Holocene transgression on the coast of the Valencia Gulf. To achieve this goal, a sedimentological and micropaleontological analysis of samples of fossil benthic foraminifera in cores from six boreholes drilled in three different wetlands (Almenara marsh, Moro marsh and Valencia lagoon) was carried out. In order to assess the extent of sea level change, at least three factors must be taken into account: 1) eustatic rise (global scale) 2) neotectonics (regional scale) and 3) the sedimentary factor (local and regional scale). Regarding the first factor, some authors have noted that the Holocene transgression reached +1 m above the current sea level in this area. As for the second factor, while the Valencia lagoon is located on a subsiding coast the northernmost marshes are located on a tectonically stable coast. Finally, sedimentation rates are highly variable depending on the area; whereas in the Valencia lagoon the shoreline generally shifts seawards (progradation) in the northernmost areas the coast is currently undergoing retrogradation, although the anthropic factor clearly interferes with this pattern. One of the main conclusions is that in the Valencian coast the Holocene maximum relative sea level did not exceed the present-day one, except in the case of the subsiding area of the Valencia lagoon. The calculation of sedimentation rates, the relative sea-level curve and the evolution of the water column in the different wetlands seem to corroborate it. Radiocarbon and AAR analyses allowed us to date the maximum extent of the Holocene transgression on the Valencian coast at around 5500 cal yr BP in all cases. Despite the different subsidence the three studied wetlands reflected the predominant marine influence until 5500–5200 BP, which was later followed by a growing fluvial or continental incidence, when glacioeustatic adjustments defined the patterns of coastal progradation. [Display omitted] • Location of the MIS 1 coastline position in three West Mediterranean wetlands. • The global Holocene eustatic rise invaded the three wetlands at least 5300 years BP. • Subsidence rate determined different MIS 1 relative sea-level rise in the wetlands. • Tectonic stability in the northern wetlands involved slower relative sea-level rise. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
15. Formulating a 100-year strategy for managing coastal hazard risk in a changing climate: Lessons learned from Hawke's Bay, New Zealand.
- Author
-
Ryan, E.J., Owen, S.D., Lawrence, J., Glavovic, B., Robichaux, L., Dickson, M., Kench, P.S., Schneider, P., Bell, R., and Blackett, P.
- Subjects
ABSOLUTE sea level change ,CLIMATE change ,COASTAL zone management ,EMERGENCY management ,PHYSIOLOGICAL adaptation ,DECISION making - Abstract
Decision-makers, managers and communities in low-lying coastal regions face many challenges in planning for and adapting to escalating coastal hazard risk, given uncertainty about sea-level rise and complex and contested environmental and socio-economic futures. Collaborative and participatory approaches can help to address such challenges and enable proactive adaptation. However, there is limited empirical evidence of such approaches yielding outcomes that can genuinely be described as shifting business as usual, and fewer still that have informed institutional change. This paper provides such evidence based on an assessment of a novel collaboration between local government, Māori, stakeholders, community members, consultants and researchers in the formulation of a 100-year coastal hazard management strategy in Aotearoa New Zealand. Thematic analysis of interviews, surveys and workshop materials was used to distil lessons learned by participants involved in formulating this anticipatory long-term strategy. Results indicated the importance of deliberative, flexible and transparent governance processes that can enable collaboration amongst Māori, local and region-wide stakeholders, in a process consistent with and supported by the national governmental frameworks, and regulatory and non-regulatory measures. The importance of aligning scientific, local and Indigenous knowledges is highlighted. Furthermore, novel tools and methodologies were used in the strategy formulation process, hitherto not applied in a real-life coastal decision-making process, to address changing risk over time and uncertainties. This enabled the tailoring of strategic planning and decision processes to reflect local contexts and governance interactions. Adaptive pathways were developed to enable short-term actions to be taken while leaving open long-term options and alternative pathways available for future adjustment as the hazards and impacts intensify. The lessons learned from the development of the coastal management strategy offer insights to support future collaborative decision-making processes in climate change adaptation. They advance scholarly understanding about how sea-level rise risks can be addressed in a long-term strategic formulation process in a dynamic and 'fit-for-purpose' manner. [Display omitted] • We thematically analysed the formulation of a 100-year coastal hazards strategy. • Key themes emerged to reveal lessons learned from the process. • Collaborative and flexible governance processes contributed to building trust. • Proactive, tailored decision tools enabled development of adaptation pathways. • Scientific, technical, local and Indigenous knowledges were incorporated. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
16. The progradational Curumim barrier in southern Brazil: An archive of sea-level changes, and cyclic aeolian activity in the Holocene.
- Author
-
Dillenburg, Sergio R., Barboza, Eduardo G., Hesp, Patrick A., Rosa, Maria Luiza C.C., Caron, Felipe, and Guadagnin, Felipe
- Subjects
- *
HOLOCENE Epoch , *OPTICALLY stimulated luminescence dating , *ABSOLUTE sea level change , *SAND waves , *SAND , *COASTS - Abstract
This paper discusses a model of coastal barrier progradation where the development of a prograded plain was a product of the successive formation of foredune ridges followed by their burial by transgressive sand sheets and dunefields. The results are based on direct lithological data from drill holes and geomorphological analyses, indirect geophysical data (GPR), and 14C and OSL dating. Barrier progradation started at 6.69 ka (OSL) or 7.2 ka (14C), under sea-level rise. At around 5.0 ka (OSL), or thereabouts, a forced regression condition started to operate, when sea-level started to fall after it reached a maximum of 2.34 ± 0.8 m. During barrier progradation sets of foredunes were formed, and at least some of them were buried by sands of transgressive dunefields (TDF), which later evolved to transgressive sand sheets (TSS). A total of 11+ phases of TSS and a modern phase of TDF were formed in a time span of 6.69 ka (OSL) or 7.2 ka (14C), corresponding to one phase formed at each 560 or 600 yrs. Two models of possible development of the surface of Curumim barrier are proposed. • Arare record of aforedune plain buried by transgressive sandsheets formation. • The cyclic formation of transgressive dunefieldsand transgressive sand sheets. • The foredune/beach contact as a proxy of sea-level position. • Distinct contributions of normal and forced regressionon barrier progradation. • Possibletransformation of a transgressive dunefield in a transgressive sand sheet. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
17. Formation and evolution of barrier coast under condition of sand scarcity; an example from the Polish coast of the southern Baltic sea.
- Author
-
Sydor, Paweł and Uścinowicz, Szymon
- Subjects
- *
CORE drilling , *COASTS , *ABSOLUTE sea level change , *SAND , *SCARCITY , *SEA level - Abstract
The formation and evolutionary history of intracontinental, tideless sea barrier coasts is still poorly known in comparison to open-ocean and tidal sea barrier systems. This paper describes the morpho-geological structure of the barriers and its substrate along a 90-km section of the middle part of the Polish southern Baltic coast. The main goal of the study is a better insight into the evolution of the barriers in case of sand scarcity and relations to sea level changes. The study area was examined by analysis of the published and historical data from 120 borehole profiles supplemented by new 18 core drillings. In addition to lithological and biostratigraphical data, a large set of radiocarbon ages was acquired and analysed. The barriers during its whole middle and late Holocene history were retrogradational despite of varied geological and morphological features of its substrate. The average rate of barrier's retreat has shown considerable variation in a close relation to the rates of sea-level rise. During the period 8500-7500 yr b2k when the sea level rose by 6–5 mm/yr, the coast retreated ca. 4.6–3.5 m/yr. Between 7500 and 6000 yr b2k, the sea-level rise slowed down to ca. 1.7 mm/yr and the rate of coastline retreat fell to ca. 1.0 m/yr. During the last 6000 years, coastal retreat slowed down to ca. 0.3 m/yr as the average sea level rise was ca. 0.5 mm/yr. The permanent retrogradational history of the barrier coast, even in the case of sand availability in the barrier's substrate, is explained by the existence of a divergence zone of longshore currents and a related source zone for the alongshore sandy streams. The divergence zone is present within the study area not only today, but it has existed most probably also at least since the beginning of the late Holocene. As a result, the erosional trend (sand scarcity) dominates here, which contributes to the presence of retrogradational barriers. • Recognition of morpho-geological structure of the barrier and its substrate. • New middle and late Holocene relative sea-level curve from southern Baltic Sea. • The evolution of the barriers in case of sand scarcity and relations to sea level changes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. A multiproxy approach to understanding the impact of the Storegga tsunami upon Mesolithic hunter-fisher-gatherers across different regions of western Norway.
- Author
-
Walker, James, Nyland, Astrid J., Bergsvik, Knut Andreas, Kilhavn, Håvard, Gibbons, Steven J., and Glimsdal, Sylfest
- Subjects
- *
TSUNAMI warning systems , *TSUNAMIS , *ARCHAEOLOGICAL site location , *MESOLITHIC Period , *ABSOLUTE sea level change , *ENVIRONMENTAL degradation - Abstract
The Storegga tsunami (c. 8150 cal BP) is geologically well attested from various isolation basins across the west Norwegian coast. Ascertaining the impact it had upon the Mesolithic peoples who lived through it, however, remains a difficult proposition; one further complicated by broadly synchronic processes of climate change and sea-level rise. This paper presents a regional scale approach to addressing this matter through a multiproxy study comprising: 1) the performance of a new numerical tsunami run-up simulation for six different focus areas; 2) characterising the impact of the tsunami upon key resource base ecosystems; 3) characterising the potential for complication arising from contemporaneous processes of environmental change caused by the '8.2 ka BP event', and sea-level rise associated with the early-mid Holocene 'Tapes' transgression, and 4) the reconstruction of temporal traditions in site location relative to the contemporary palaeoshoreline within the six focus areas used for the numerical simulation. Severity of run-up and inundation is found to be acutely variable according to coastal geomorphology and topography, bathymetry, and proximity to the propagation centre. Although the tsunami may have had a severely negative impact upon some coastal inhabitants and ecosystems, it is not possible from current evidence to reliably infer unequivocal impacts relating to the tsunami through the archaeological record, nor is it clear that impact upon key ecosystem components was necessarily lasting, widespread, or even entirely negative for coastal hunter-fisher-gatherers. Variability in projected run-up and settlement histories highlight the appeal of regionally based approaches to reconstructing impact, at least where data resolution may permit. The tsunami does not appear to have prompted a lasting shift away from coastally oriented ways of life. • First results of onshore run-up modelled for Storegga tsunami (8.15 kya) in W. Norway. • Run-up and consequent inundation varied considerably according to geomorphology. • Regional variability in archaeological site locations from north to south. • Archaeological data show that shore-bound settlements continued after the tsunami. • Environmental damage was probably severe, but variable in extent and short-lived. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Evaluation of coastal protection strategies and proposing multiple lines of defense under climate change in the Mekong Delta for sustainable shoreline protection.
- Author
-
Le Xuan, Tu, Ba, Hoang Tran, Thanh, Vo Quoc, Wright, David P., Hasan Tanim, Ahad, and Tran Anh, Duong
- Subjects
INTEGRATED coastal zone management ,CLIMATE change ,COASTAL zone management ,COASTS ,BEACH erosion ,COASTAL changes ,ABSOLUTE sea level change ,FOREST restoration - Abstract
Coastal protection measures and management play an important role in coping with coastal disasters and climate-induced sea-level rise. In this study, the success and failure of typical coastal protection works of the Vietnamese Mekong Delta (VMD) are reported and documented from field observations over a study period of 10–15 years. The coastal protection structures evaluated include revetments, geotubes, t-shaped bamboo fences, Pile-rock breakwaters, Busadco's breakwaters, Semi-Circular breakwaters, and Hollow triangle breakwaters. This paper briefly reviews the current situation of coastline erosion problem and accretion in the VMD and illustrates the severity of the current erosion rate that threatens the safety of coastal communities. The paper then evaluates the advantages and disadvantages of various coastal management approaches currently in practice in the VMD to classify different types of possible measures for coastal management with the aim to find holistic measures for planning which require low construction investment. Integrated coastal management and planning are outlined at a regional scale followed by the lessons learned from the previous coastal protection works, and finally the multiple lines of defense (MLD) solution is proposed, which is a green infrastructure inspired nature-based solution. The MLD solution can improve biodiversity, facilitate mangrove forest restoration, and ensure sustainable livelihoods for local communities. Integrated coastal planning and management solutions that are based on the MLD principle are expected to withstand coastal disasters under future climate change, and sea-level rise on the VMD. [Display omitted] • Review of coastal erosion/accretion issues and protection measures in the VMD. • Evaluation of advantages and disadvantages of coastal protection methods. • Measures for integrated and sustainable coastal management are classified. • Multiple lines of defense solution proposed for climate change adaption in the VMD. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. Adjustment or transformation? Disaster risk intervention examples from Austria, Indonesia, Kiribati and South Africa.
- Author
-
Fekete, Alexander, Fuchs, Sven, Garschagen, Matthias, Hutter, Gérard, Klepp, Silja, Lüder, Catharina, Neise, Thomas, Sett, Dominic, von Elverfeldt, Kirsten, and Wannewitz, Mia
- Subjects
FLOOD risk ,WATER shortages ,ABSOLUTE sea level change ,SOCIAL impact ,RISK managers ,CLIMATE change - Abstract
Change triggered by natural hazards such as pluvial and coastal floods, sea-level rise as well as risks resulting from water scarcity are highly dynamic and related to the effects of ongoing climate change. Whether and how societies adapt, adjust, change, or transform because of climate change and related risks, is a currently debated topic. This question demands revisiting and comprehensively addressing existing theoretical foundations of transformations in risk management strategies and in risk governance to find effective ways to deal with climate change effects and their social consequences. Hence, the paper discusses current developments in transformation research and exemplifies this discussion with four interdisciplinary cases, which the co-authors reported in previous publications. Findings from Austria include a governance change within flood risk management related to zonation. Relocation in Indonesia and Kiribati showcases its cultural, behavioural as well as economic implications. Water scarcity in South Africa underlines the importance of behavioural change to enable the structural storage of rainwater. This paper analyses aspects of adjustment or transformation in these four examples. This may inform risk managers, decision-makers, practitioners, and planners dealing with natural hazards related to climate change how to conceptualise their (re-)actions. • Differences between the terms adaptation, adjustment, change, and transformation are analysed and working definitions suggested. • Triggers and interventions are analysed whether they express adaptation, adjustment, or transformation. • Empirical cases are re-analysed whether the changes therein exhibit elements of adaptation, adjustment, or transformation. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
21. 3D depositional architecture of a wave-dominated delta in a far-field GIA region: The case of the São Francisco delta, Brazil.
- Author
-
Dominguez, José Maria Landim, Guimarães, Junia Kacenelenbogen, Stattegger, Karl, and Tanajura, Elmo Leonardo Xavier
- Subjects
- *
BEACH ridges , *GLACIAL isostasy , *ABSOLUTE sea level change , *SEA level , *TOPOGRAPHY , *RADIOCARBON dating - Abstract
The São Francisco delta in eastern Brazil is considered a classical example of a wave-dominated delta constructed in a glacial isostatic adjustment (GIA) far-field region. Although this delta is widely mentioned in the international literature, few details about its sedimentary architecture have been published. In this paper, we use a new dataset consisting of 15 boreholes and 26 radiocarbon datings to discuss the 3D architecture of the delta and the role played by GIA far-field effects in delta construction. The delta plain consists of a 10–12 m thick littoral sand sheet that progrades over a muddy subaqueous clinoform, forming a compound clinoform. Delta construction began between 8.4 and 7.2 ka BP and included a stage of normal regression that lasted until 5.7 ka BP, followed by a stage of forced regression. The transition between these two stages is marked by the highest position of the sand–mud transition in the boreholes. This forced regression is due to a 3–4-m drop in relative sea level since the mid-Holocene, which is characteristic of GIA far-field regions. Additionally, as a consequence of this drop in relative sea level, there is a progressive increase in the altitude of the beach-ridge deposits continentward, which combined with the development of extensive dune fields in the later stages of delta construction, contributes to the increased resilience of the delta to ongoing sea-level rise. The 3D architecture of the delta was strongly influenced by antecedent topography. The delta was built on a bathymetric depression on the shelf that almost entirely traps the sediment load of the São Francisco River. The uneven relief inside this bathymetric depression ultimately controlled lateral variations in the total thickness of the delta edifice. • Two-stage delta construction in GIA far-field regions: normal and forced regression. • Drop in sea level since mid-Holocene in GIA far-field regions increases delta resilience to ongoing sea-level rise. • Antecedent topography strongly controlled the delta 3D architecture. • 3D architecture of the São Francisco wave-dominated delta is presented for the first time. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
22. A state-of-the-art review on fibre-reinforced geopolymer composites.
- Author
-
Abbas, Al-Ghazali Noor, Aziz, Farah Nora Aznieta Abdul, Abdan, Khalina, Nasir, Noor Azline Mohd, and Huseien, Ghasan Fahim
- Subjects
- *
FIBROUS composites , *EMISSIONS (Air pollution) , *CLIMATE change , *ABSOLUTE sea level change , *EARTH temperature , *SISAL (Fiber) , *GREENHOUSE gases - Abstract
• The research papers related to FRGC were reviewed and classified into sub-categories depending on the fibres type. • The effects of different fibres types and their parameters on the physical, mechanical and microstructural properties of geopolymer composites have been investigated. • The research lacking in the FRGC field was highlighted. • FRGC can be a potential solution for structural applications with excellent performance. Cement industries that produce the primary component of concrete remain one of the main challenges to the world since they change the climate and possess a negative impact on sustainability. Due to climate change, the earth's temperature has increased and reached a higher level in recent years that in turn results in a distressed environment for all living beings for survival. All the consequences that scientists warned would occur as a result of global climate change in the past are now occurring: rapid sea-level rise, sea ice loss and longer, more intense heat waves. Geopolymer materials are considered as one of the solutions to reduce greenhouse gas emissions from the cement industry. Geopolymers provide the industry with great potential and sustainable alternatives to ordinary Portland cement (OPC). However, when subjected to flexure and tension stresses, the geopolymer's inherent brittleness displays drawbacks like OPC; both need fibre reinforcement to control cracks propagation, enhance toughness and deformation. As a result, the development of fibre-reinforced geopolymer composites (FRGC) has attracted increased attention, with a wide range of fibres being used. This study presents a review of the published papers on the FRGC; the research papers were reviewed and classified into sub-categories depending on the fibres type. The physical, mechanical and microstructural properties of geopolymer composites were discussed in detail. By reviewing the literature, it is evident that the FRGC can be a potential solution for structural applications with excellent performance. The improvements in geopolymer properties with the fibre addition have paved the way for further studies in this regard to exploring its performance in unused areas. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
23. Reconstructing Holocene sea-level change from coastal freshwater peat: A combined empirical and model-based approach.
- Author
-
Gehrels, W. Roland and Anderson, William P.
- Subjects
- *
ABSOLUTE sea level change , *HOLOCENE Epoch , *PEAT , *TERRITORIAL waters , *FRESH water , *PERMEABILITY - Abstract
Abstract: This paper presents a novel method to reconstruct sea-level change in coastal freshwater back-barrier marshes. Freshwater environments have long been considered to be unsuitable for the reconstruction of Holocene sea-level changes as they provide limiting, rather than precise, sea-level index points. We recorded the stratigraphy of a small beach and back-barrier coastal Phragmites (reed) marsh at Hallsands, south Devon, southwest England, using hand-drilled cores and ground-penetrating radar, and collected five new sea-level index points from the base of a Holocene peat sequence to refine the regional Holocene relative sea-level curve. We demonstrate that the samples, despite their freshwater origin, yield accurate sea-level index points as determined from the quantifiable relationship between tide levels and groundwater. By means of water-table monitoring and groundwater modelling we show that the primary controls on the water table in the marsh are: (1) stratigraphy; (2) peat permeability; and (3) recharge rates in the back-barrier marsh. The five index points document relative sea-level positions between 7200 and 2400calyr BP. Three points are in good agreement with previously collected regional data from intertidal deposits and two points usefully fill gaps in the existing reconstruction. An amended Holocene relative sea-level curve for south Devon, based on 30 data points, is presented. We conclude that the combined approach of data collection and modelling used in this paper can be applied to similar coastal settings around the world and allows the collection of sea-level index points from locations not previously thought suitable for this purpose. [Copyright &y& Elsevier]
- Published
- 2014
- Full Text
- View/download PDF
24. A Bayesian probabilistic approach for impacts of sea level rise on coastal engineering design practice.
- Author
-
Rajabalinejad, M. and Demirbilek, Z.
- Subjects
- *
ABSOLUTE sea level change , *COASTAL engineering , *BAYESIAN analysis , *PROBABILITY theory , *ENGINEERING design , *OCEAN engineering , *HYDRAULIC structures - Abstract
Abstract: The real impact of sea level rise (SLR) on coastal and ocean engineering infrastructures is anticipated to be significant. The associated huge costs of coastal flooding and lasting socio-economic crisis would require planners, decision-makers and engineers to use effectively all available knowledge and data to optimize flood defense protection systems. In this paper, we introduce a Bayesian approach that integrates knowledge from previous performance history of structures (data, models and analysis) with more recent information from the simulations performed using the latest data, methods and modeling technology. These two sets of knowledge and information on past and present status of system contain various uncertainties and errors introduced by different input sources and analysis methods. We employ the concept of global uncertainty to quantify the total uncertainty affecting the design, functionality and maintenance of coastal flood defense systems in order to reduce damages resulting from the SLR and other extreme water level changes (e.g., storm surges by hurricanes, increased precipitation and ice melting). Our objective in this paper is to show coastal engineers how to use the prior knowledge with the most current information to improve the safety of flood defense systems. We demonstrate the proposed method in an example for the failure analysis of the 17th Street Flood Wall in New Orleans, where we estimate uncertainties that affected the design of the I-wall. We provide a methodology that integrates the contribution of SLR with all other available prior information to determine uncertainty levels for failure analysis of the flood defenses. Various uncertainties are present in engineering practice, explicit or implicit, and quantification of these is essential to safety and efficacy of coastal flood protection systems. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
25. Analysing the 100year sea level record of Leixões, Portugal
- Author
-
Araújo, I.B., Bos, M.S., Bastos, L.C., and Cardoso, M.M.
- Subjects
- *
ABSOLUTE sea level change , *TIDES , *GAGES , *TIMESTAMPS , *DATA quality , *ATMOSPHERIC pressure , *GLACIAL isostasy - Abstract
Summary: A new data set from the tide gauge at Leixões (North–West Portugal) has recently been transferred from its paper format into a digital time series of hourly sea level values. By measuring sea level variations since 1890, this tide gauge station is one of the few in the world with over 100yr of digitised hourly records and the longest for the South West of Europe and Iberian Peninsula. This paper presents the procedures adopted to recover the Leixões sea level data from paper chart records as well as the data quality control and data editing methodologies. The mean rate of sea level change between 1906 and 2008 is −0.70±0.27mmyr−1, which does not agree with the global mean sea level rise of 1–2mmyr−1. No evidence for vertical land movement was found and Global Isostatic Adjustment influence on sea level, at this location, can be neglected. It is likely that prevailing weather systems in the North Atlantic, especially in the winter, and local atmospheric pressure, influence sea levels at Leixões. A further contribution is found from tides and surges. The evolution of the port cannot be ignored when trying to understand sea level change. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
26. Tidal notches: A sea-level indicator of uncertain archival trustworthiness
- Author
-
Pirazzoli, Paolo A. and Evelpidou, Niki
- Subjects
- *
TIDES , *EROSION , *ABSOLUTE sea level change , *CARBONATE rocks , *FOSSILS , *LITTORAL zone , *CASE studies - Abstract
Abstract: In this paper, after a short summary on the processes and rates of bioerosion that contribute to the deepening of a tidal-notch profile, some Mediterranean case-studies are presented, where a tidal notch is prevented either from forming or from being preserved. Furthermore, as shown also in a complementary paper, the recent global sea-level rise is preventing the development of new tidal notches in the present mid-littoral zone. This very useful sea-level indicator, of past temporary standstills of the relative sea level in carbonate rock areas, is of great value in assisting interpretations of relative sea-level change in locations where it is preserved. The possibilities of absence of formation or of preservation, however, imply that it should be interpreted carefully before reconstructing local relative sea-level histories. In particular, the lack of fossil tidal notches cannot be relied upon to interpret the absence of past periods of relative sea-level stabilization. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
27. Spatial distribution of sea-level markers on Lesvos Island (NE Aegean Sea): Evidence of differential relative sea-level changes and the neotectonic implications
- Author
-
Vacchi, Matteo, Rovere, Alessio, Zouros, Nickolas, Desruelles, Stéphane, Caron, Vincent, and Firpo, Marco
- Subjects
- *
SPATIAL analysis (Statistics) , *ABSOLUTE sea level change , *NEOTECTONICS , *GEOMORPHOLOGY , *PALEOSEISMOLOGY , *RADIOCARBON dating - Abstract
Abstract: The aim of this study is to provide new data on relative sea-level changes and neotectonics of the northeastern Aegean Sea region (Eastern Mediterranean) through the analysis of the coastal geomorphology of Lesvos, the third largest Greek island. There is a paucity of presently available data in this sector of the Aegean Sea, which is a tectonically active area strongly controlled by the North Anatolian Fault. In this paper, morphological, biological and sedimentary records of paleo-sea levels have been used to reconstruct relative sea-level changes, to identify variations in the tectonic regimes as well as to assess the paleoseismicity in the studied areas. According to the results, late Quaternary relative sea-level changes at Lesvos were not homogenous and variations in the tectonic setting played a crucial role in the coastal evolution. The NW-SE trending faults on the southern shore of the island control a significant uplift affecting about 30km of coastline. This uplift trend is controlled by the footwall of the Lesvos Fault, a major offshore normal fault that has been subject to relatively little quantitative investigation. Radiocarbon dating indicated that the last co-seismic uplift took place at 3365–3963calyr BP and resulted in about 0.75m of vertical displacement. In contrast, all the paleo-sea-level markers mapped in the northeastern sector were presently underwater and, despite the high seismicity of the area, no evidence of coastal uplift was observed in this part of the island. Thus, the paper provides the first field evidence of a differential late Quaternary evolution of Lesvos Island. In addition, results represent the first quantitative information on the activity of the Lesvos Fault, suggesting a reconsideration of its importance in the neotectonics of the area. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
28. Assessing the costs of sea-level rise and extreme flooding at the local level: A GIS-based approach.
- Author
-
Lichter, Michal and Felsenstein, Daniel
- Subjects
ABSOLUTE sea level change ,FLOODS ,COST analysis ,GEOGRAPHIC information systems ,LAND use ,CAPITAL stock ,COASTS - Abstract
Abstract: This paper presents a systematic framework for assessing the costs of sea-level rise (SLR) and extreme flooding at the local level. The method is generic and transferable. It is built on coupling readily available GIS capabilities with quantitative estimates of the effects of natural hazards. This allows for the ex ante monetization of the main costs related to different scenarios of permanent inundation and periodic flooding. This approach can be used by coastal zone planners to generate vital information on land use, capital stock and population at risk for jurisdictions of different sizes. The simple mechanics of the method are presented with respect to two examples: one relates to the two largest coastal cities in Israel (Tel Aviv and Haifa) and the other to the Northern Coastal Strip region containing a variety of small towns and rural communities. The paper concludes with implications for coastal zone planning praxis. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
29. The impact of future sea-level rise on the European Shelf tides
- Author
-
Pickering, M.D., Wells, N.C., Horsburgh, K.J., and Green, J.A.M.
- Subjects
- *
ABSOLUTE sea level change , *CONTINENTAL shelf , *TIDES , *RESONANCE , *ENERGY dissipation - Abstract
Abstract: This paper investigates the effect of future sea-level rise (SLR) on the tides of the northwest European Continental Shelf. The European shelf tide is dominated by semidiurnal constituents. This study therefore focuses primarily on the changes in the M2 tidal constituent and the spring and neap tidal conditions. The validated operational Dutch Continental Shelf Model is run for the present day sea-level as well as 2 and 10m SLR scenarios. The M2 tidal amplitude responds to SLR in a spatially non-uniform manner, with substantial amplitude increases and decreases in both scenarios. The M2 tidal response is non-linear between 2 and 10m with respect to SLR, particularly in the North Sea. Under the 2m SLR scenario the M2 constituent is particularly responsive in the resonant areas of the Bristol Channel and Gulf of St. Malo (with large amplitude decreases) and in the southeastern German Bight and Dutch Wadden Sea (with large amplitude increases). Changes in the spring tide are generally greater still than those in the M2 or neap tides. With 2m SLR the spring tidal range increases up to 35cm at Cuxhaven and decreases up to −49cm at St. Malo. Additionally the changes in the shallow water tides are larger than expected. With SLR the depth, wave speed and wave length (tidal resonance characteristics) are increased causing changes in near resonant areas. In expansive shallow areas SLR causes reduced energy dissipation by bottom friction. Combined these mechanisms result in the migration of the amphidromes and complex patterns of non-linear change in the tide with SLR. Despite the significant uncertainty associated with the rate of SLR over the next century, substantial alterations to tidal characteristics can be expected under a high end SLR scenario. Contrary to existing studies this paper highlights the importance of considering the modification of the tides by future SLR. These substantial future changes in the tides could have wide reaching implications; including for example, correctly calculating design level requirements for flood defences, the availability of tidal renewable energy and dredging requirements. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
30. Carbonate-clastic sedimentation in the Parnaiba Basin, northern Brazil: Record of carboniferous epeiric sea in the Western Gondwana.
- Author
-
Medeiros, Renato Sol Paiva de, Nogueira, Afonso César Rodrigues, Silva Junior, José Bandeira Cavalgante da, and Sial, Alcides Nobrega
- Subjects
- *
FOSSIL microorganisms , *SEAS , *SETTLING basins , *ABSOLUTE sea level change ,GONDWANA (Continent) - Abstract
The transgressive-regressive events due to changes in the eustatic sea level represent the occurrence of an epeiric sea in Western Gondwana. This event is recorded in the carbonate-siliciclastic succession exposed in the central portion of the Parnaiba Basin, Northern Brazil, mainly represented by densely fossiliferous deposits, with mollusks, brachiopods, corals and microfossils, related to the upper member of the Piauí Formation. Outcrop-based facies/microfacies and stratigraphic analysis of this succession allowed the individualization of two facies associations (FA), representative of a shallow carbonate platform system adjacent to a coastal dune field. The FA1– dune field/interdune, comprises well sorted, intensely biortubated, fine to medium-grained sandstone with even parallel and tabular cross stratification, as well as translatent climbing ripple cross-lamination. FA2-shallow sea deposits consist of fossiliferous pelletal carbonate and microspar carbonate layers, laterally continuous for hundreds of meters, interbedded with centimetric beds and lenses of organic shale with small pyrite crystals. Covariant values of positive δ18O carb and negative δ13C carb for the carbonate profiles, together with intense substitution of primary constituents by dolomite and an abundance of associated organic matter contributed towards determining an organogenic dolomitization model. Although the Pennsylvanian records a long icehouse event, glacioeustatic fluctuations were common during the Moscovian and Kasimovian. The icehouse periods contributed to the semi-arid to desert conditions that shaped the aeolic environments of the Piauí Formation. Later greenhouse events favored a rise in the sea level and development of an extensive epicontinental Pennsylvanian sea that extended throughout Western Gondwana called the Itaituba-Piauí sea in this paper, which connected the Andean, Solimões, Amazonas and Parnaíba basins. • Carbonate-clastic sedimentation in the Penssylvanian of Parnaíba Basin. • Coastal wind dunes from the top of the Piauí Formation. • Piauí Formation evidences the epicontinental sea in West Gondwana. • Dolomitization and δ13C carb and δ18O carb of shallow sea carbonates in the Piauí Formation. • The carbonate factory on the great lakes/sea were ceased. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
31. Reconstructing the Last Glacial Maximum ice sheet in the Weddell Sea embayment, Antarctica, using numerical modelling constrained by field evidence
- Author
-
Le Brocq, A.M., Bentley, M.J., Hubbard, A., Fogwill, C.J., Sugden, D.E., and Whitehouse, P.L.
- Subjects
- *
ICE sheets , *ABSOLUTE sea level change , *MELTWATER , *CONTINENTAL shelf , *LAST Glacial Maximum , *NUMERICAL analysis - Abstract
Abstract: The Weddell Sea Embayment (WSE) sector of the Antarctic ice sheet has been suggested as a potential source for a period of rapid sea-level rise – Meltwater Pulse 1a, a 20m rise in ∼500 years. Previous modelling attempts have predicted an extensive grounding line advance in the WSE, to the continental shelf break, leading to a large equivalent sea-level contribution for the sector. A range of recent field evidence suggests that the ice sheet elevation change in the WSE at the Last Glacial Maximum (LGM) is less than previously thought. This paper describes and discusses an ice flow modelling derived reconstruction of the LGM ice sheet in the WSE, constrained by the recent field evidence. The ice flow model reconstructions suggest that an ice sheet consistent with the field evidence does not support grounding line advance to the continental shelf break. A range of modelled ice sheet surfaces are instead produced, with different grounding line locations derived from a novel grounding line advance scheme. The ice sheet reconstructions which best fit the field constraints lead to a range of equivalent eustatic sea-level estimates between approximately 1.4 and 3m for this sector. This paper describes the modelling procedure in detail, considers the assumptions and limitations associated with the modelling approach, and how the uncertainty may impact on the eustatic sea-level equivalent results for the WSE. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
32. An early Campanian rocky shore at Ivö Klack, southern Sweden.
- Author
-
Surlyk, Finn and Sørensen, Anne Mehlin
- Subjects
COASTS ,ANIMAL diversity ,ABSOLUTE sea level change ,GNEISS ,KAOLIN - Abstract
Abstract: Well-exposed, ancient rocky shores are rare and the associated shelly faunas are normally strongly worn and fragmented due to erosion during both sea-level rise and fall. An early Campanian rocky shore with a rich fauna is preserved at Ivö Klack in the Kristianstad Basin, southern Sweden. Ivö Klack is situated on the small, hilly island of Ivö situated in lake Ivösjön with a lake level about 6m above present-day sea level. The rocky shore was formed during a major late early Campanian transgression caused by a sea-level rise up to about 100m above present sea level. An archipelago was formed along the northern basin margin during the transgression with numerous small islands and peninsulas. The steep palaeo-coast at Ivö Klack consists of gneiss overlain in the lower part by more than 30m of kaolin in places containing large boulders of gneiss with a kaolinized outer crust. The kaolin wedges out upslope and is absent above 30–35m above lake level. The kaolin is overlain by up to 5m of muddy quartz sand with highly angular grains, representing a residue of the kaolin formed during transgressive wave and current reworking. The steep gneiss coast was rapidly transgressed by the sea in the latest early Campanian and at least 25m of onlapping coarse-grained skeletal sand, gravel and whole fossils were deposited on the clean gneiss surface during the Belemnellocamax mammilatus belemnite biozone. Large boulders of gneiss are common in the carbonates and formed distinct boulder beds at some levels but these are now quarried away. The top 6m of the preserved carbonate succession are free of boulders. The rocky surface is fairly even on a large scale, but highly irregular in detail with numerous metre-sized hummocks and boulders formed during terrestrial weathering and kaolinization. The lowest part of the shore is developed as a bench, topped by a sub-horizontal irregular platform, 20–30m wide, with large hummocks and rounded boulders. The platform passes upwards into a steep boulder-strewn slope. A well-developed glauconitized hardground with Thalassinoides burrows and several incipient hardgrounds occur in the carbonates draping the bench and lower part of the platform. They dip gently outwards and probably represent a kind of beach rock. A highly diverse benthic fauna with more than 200 shell-bearing species lived between, below and on the hummocks and boulders. It comprises bivalves, brachiopods, polychaetes, gastropods, echinoids, asteroids, bryozoans and is dominated by large oysters and includes the northernmost Late Cretaceous rudists and hermatypic corals. The remaining benthic invertebrate groups are represented by only a few species each. The non-benthic invertebrate fauna comprises four belemnite species and one rare ammonite species. The lower Campanian carbonates of the small basin have yielded an unusually diverse vertebrate fauna totalling more than 60 species, including mosasaurs, plesiosaurs, crocodiles, turtles, birds, and as many as 44 species of sharks and rays. Ivö Klack thus provides information on virtually all trophic levels in the rocky shore ecosystem and represents the most diverse rocky shore fauna known from the geological record. This paper aims at providing the framework for a series of papers on the palaeoecology of the main benthic faunal groups. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
33. Offshore wind power development as affected by seascape values on the German North Sea coast.
- Author
-
Gee, Kira
- Subjects
WIND power ,POWER resources ,ABSOLUTE sea level change ,LANDSCAPES ,LANDSCAPE assessment ,CLIMATE change - Abstract
Abstract: In Germany, the first permits have now been issued for the construction of large-scale offshore wind farms in the German Exclusive Economic Zone (EEZ). This paper focuses on perceptions of the local seascape and the role of aesthetic seascape qualities in shaping local attitudes to offshore wind farming. Based on a survey of local residents in the districts of Dithmarschen and North Frisia, it shows that aesthetic seascape perception alone cannot account for local attitudes to offshore wind farming. Three main aspects seem to come together to determine these attitudes: deeply held convictions of the sea as a natural space, deeply held views of the local landscape and linked to this local identity, and also perceptions of renewable energies in combination with attitudes to issues such as climate change and sea level rise. The paper draws some conclusions on the future of the sea as a natural space or energy space. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
34. Mean sea level trends around the English Channel over the 20th century and their wider context
- Author
-
Haigh, Ivan, Nicholls, Robert, and Wells, Neil
- Subjects
- *
OCEANOGRAPHY , *ABSOLUTE sea level change , *ARCHAEOLOGY , *GEODETIC astronomy , *CLIMATE extremes , *CLIMATE change , *WATER levels - Abstract
Abstract: This paper provides estimates of rates of change in mean sea level around the English Channel, based on an extensive new hourly sea level data set for the south coast of the UK, derived from data archaeology. Mean sea level trends are found to vary by between 0.8 and 2.3mm/yr around the Channel. The rates of mean sea level change are calculated by removing the coherent part of the sea level variability from the time series of annual mean sea level before fitting linear trends. The improvement in accuracy gained by using this approach is assessed by comparing trends with those calculated using the more traditional method, in which linear trends are fitted directly to the original records. Removal of the coherent part of the sea level variability allows more precise trends to be calculated from records spanning 30 years. With the traditional approach 50 years is required to obtain the same level of accuracy. Rates of vertical land movement are approximated by subtracting the mean sea level trends from the most recent regional estimate of change in sea level due to oceanographic processes only. These estimated rates are compared to measurements from geological data and advanced geodetic techniques. There is good agreement around most of the UK. However, the rates estimated from the sea level records imply that the geological data suggest too much submergence along the western and central parts of the UK south coast. Lastly, the paper evaluates whether the high rates of mean sea level rise of the last decade are unusual compared to trends observed at other periods in the historical record and finds that they are not. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
35. Projected sea level rise in Florida
- Author
-
Walton, Todd L.
- Subjects
- *
WATER levels , *ABSOLUTE sea level change , *OCEAN circulation , *GLOBAL temperature changes - Abstract
Abstract: Future sea level rise will lead to salt water intrusion, beach/dune recession, and many other coastal problems. This paper addresses a data based forecasting approach to provide relative sea level rise estimates at locations in Florida where historical water level data exist. Many past estimates of sea level rise have treated the rise as a linear straight line trend over the historical data set. The present paper has allowed for acceleration (or deceleration) in sea level rise to account for the possibility of anthropogenic global warming and consequent higher (than linear straight line) future sea levels similar to values noted by global climatic modelers. Results of the present analysis show sea level rise for Florida being higher than past straight line trend results. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
36. How to reconstruct trends of late Holocene relative sea level: A new approach using tidal flat clastic sediments and optical dating
- Author
-
Mauz, Barbara and Bungenstock, Friederike
- Subjects
- *
TIDAL flats , *OPTICALLY stimulated luminescence dating , *ABSOLUTE sea level change , *HOLOCENE paleoceanography - Abstract
Abstract: Assessment of ongoing relative sea level rise in NW-Europe for individual tidal basins is wanted and, consequently, a variety of methods must be available for investigations under different local conditions. The methodology presented in this paper is based on OSL (optically stimulated luminescence) dating of tidal flat sedimentary records. It uses a conceptual model that assumes that tidal flat clastic sediments record small changes in sea level trend. These changes are in NW-Europe superimposed on the general rising trend of the near-field sea level during the late Holocene (last ∼3500 years). The dating approach can be complemented by 210Pb-dating for the most recent period (last ∼100 years). This combination has the potential to bridge between contrasting short-term and long-term data about sea level change. The paper describes the model for sedimentation and the dating technique. The accuracy of the method is assessed at a test site on the East Frisian coast (North Sea, German Bight), for which independent sea level data achieved by archaeological and biostratigraphical means were available. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
37. Stratigraphic evidence of relative sea level changes produced by megathrust earthquakes in the Jalisco subduction zone, Mexico. The signature of the 1995 Colima-Jalisco earthquake (Mw 8) as a modern analogue.
- Author
-
Bustamante Fernandez, Emmanuel, Woodroffe, Sarah, Lloyd, Jeremy M., and Shennan, Ian
- Subjects
- *
RELATIVE sea level change , *THRUST faults (Geology) , *COASTAL wetlands , *SUBDUCTION zones , *EARTHQUAKES , *FOSSIL diatoms , *EARTHQUAKE hazard analysis , *COASTAL sediments , *ABSOLUTE sea level change - Abstract
Geological evidence of megathrust earthquakes along the Mexican Pacific coast relies predominantly on tsunami deposits. Records of coseismic relative sea-level changes are scarce even though such evidence can complement and constrain tsunami records, providing information to reconstruct past earthquake rupture dimensions to improve the earthquake hazard assessment of the region. This paper provides the first diatom-based quantitative reconstruction of coastal subsidence along the Mexican subduction zone through the analysis of coastal wetland sediments. We use the stratigraphic signature of the 1995 Colima-Jalisco earthquake (M w 8.0) as this earthquake is instrumentally well-constrained, allowing us to evaluate our findings and establish approaches to investigate earlier earthquakes. Deposits beneath the wetland Estero Potrero Grande reveal a stratigraphic sequence, < 28 cm beneath the wetland surface, that resembles a signature of rapid submergence. This sequence consists of a horizontal bed of silt with highly humified organic matter abruptly overlain by a horizontal bed of grey silt. The abrupt stratigraphic contact between the two units extends across >1 km of the wetland. Using 14C ages and 137Cs chronohorizons to build an age-depth model, we estimate the age range (1985–2003 CE) and mean age (1995 CE) of this abrupt stratigraphic contact, coincident with the year of the earthquake. Three elemental log-ratios (S/Zn, Br/Zn and Ca/Zn) indicate an abrupt increase of salinity across the stratigraphic contact, which we interpret as marsh submergence recording coseismic coastal subsidence, reflected as relative sea-level rise. Fossil diatom assemblages confirm this trend, and through quantitative approaches we estimate its magnitude (−0.06 ± 0.08 m and − 0.11 ± 0.23 m), which is comparable with coastal subsidence measured by geodetic instruments. Our records reveal a millimetric spike of sand, which we interpret as a signature of the tsunami that accompanied this great earthquake. These findings demonstrate that coastal wetland sediments from the Mexican Pacific coast can record tectonic induced relative sea-level changes. This approach can allow us to better understand the long-term spatial and temporal behavior of this subduction zone. • Deposits beneath the costal wetland Estero Potrero Grande record coastal subsidence produced by the 1995 Colima-Jalisco earthquake (M w 8.0). • The lithological expression of this event, an organic silt- silt couplet, was mapped for over 1 km across the wetland. • Elemental log-ratios and diatom assemblages are the proxies that reveal the abrupt increase of salinity conditions above the stratigraphic contact. • Through a diatom-based quantitative approach we estimate the magnitude of coastal subsidence and relative sea level changes before, during and after this earthquake. • Sediment gran size analyses reveal the occurrence of a high-energy event, interpreted as the signature of the tsunami produced by this earthquake. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. How should storm surge barrier maintenance strategies be changed in light of sea-level rise? A case study.
- Author
-
Trace-Kleeberg, Sunke, Haigh, Ivan D., Walraven, Marc, and Gourvenec, Susan
- Subjects
- *
ABSOLUTE sea level change , *STORM surges , *FLOOD control , *WATER levels , *BARRIER islands , *CITIES & towns , *STORMS - Abstract
Sea-level rise and changes in storminess, together with population growth and coastward migration, are increasing the risks of coastal flooding. The impacts are amplified in coastal cities due to the high concentration of inhabitants, infrastructure and services in low lying areas. Many coastal cities are located in estuaries, and storm surge barriers are often constructed to provide flood protection in these areas with long exposed coastlines. For these complex and unique structures, maintenance is vital to ensure they remain reliable and comply with legal protection standards. To ensure safe conditions for workers, storm surge barriers typically define water level thresholds, at which maintenance work must stop when these water levels are reached or exceeded. This paper evaluates the changes in past and future water levels exceeding the maintenance threshold to inform management, maintenance and operation strategies, and design, of storm surge barriers. The Maeslant barrier in Rotterdam, Netherlands is used as a case study to test this analysis. Water levels from measurements taken at the Hoek van Holland tide gauge are compared to the maintenance threshold level. The number of past threshold exceedances is determined and the sensitivity of exceedances to threshold level are assessed. Results show that the maintenance threshold has been exceeded 991 times of which 13% occurred during the maintenance season. Conversely, there were periods in the storm season when water levels were below the maintenance threshold and work could have been carried out safely. The effect of sea-level rise and natural inter-annual tidal cycles on future threshold exceedances is also assessed. Findings reveal that the maintenance window will shift earlier in the year and narrow until exceedances of the maintenance threshold occur regularly all year around. With 1 m sea-level rise maintenance threshold exceedances are likely to occur regularly all year around by 2048. This analysis highlights that maintenance strategies at the Maeslant barrier will need to be adapted for the barrier to remain operational until its design life of 2 100. This is due to the increase in maintenance threshold exceedances resulting from natural interannual tidal cycles combined with sea-level rise. This analysis framework is applicable to existing barriers worldwide to assess future intervention points and for barriers in the design phase to verify the implications of design decisions on planned maintenance. • To date, the effect of sea-level rise and interannual tidal cycles on planned maintenance has not been assessed. • Barrier maintenance strategies will have to be adapted for barriers to remain operational for their intended design life. • Sea-level rise will result in occasions when the tide alone exceeds the maintenance threshold. • Interannual tidal cycles play a strong role in modulating maintenance threshold exceedances. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Geopolitics and humiliation: The 'sinking islands' of Tuvalu.
- Author
-
Saddington, Liam Ryder and Hills, Tiger
- Subjects
- *
HUMILIATION , *GEOPOLITICS , *ABSOLUTE sea level change , *SMALL states - Abstract
Emotions play a key role within geopolitics; spatial representations draw upon, create, and reinforce emotional responses within and from political actors. Bringing together critical literature on emotion and geopolitics, this paper sets out to examine the underexplored ways in which humiliation features in geopolitical discourse and practice. Through elite interviews and participant observation in the South Pacific at the 50th Pacific Islands Forum in August 2019, we analyse the impact of popular representations of Tuvalu in relation to sea-level rise on Tuvaluan diplomats. In doing so, we argue that atolls figure within climate politics as not only harbingers of potential climate futures, but also as objects of humiliation, ridicule, and mockery. Further, we elaborate on two components of humiliation. Firstly, that humiliation creates a hierarchical power relationship through the (neo-colonial) production and subsumption of an Other; and secondly, that humiliation relies on and undermines existing relationships and is something that is seen, felt, and heard – it is not only emotive for the actor being humiliated but is directed towards and reaches a wider audience. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
40. Comparison of dynamic cobble berm revetments with differing gravel characteristics.
- Author
-
Foss, Ollie, Blenkinsopp, Chris E., Bayle, Paul M., Martins, Kévin, Schimmels, Stefan, and Almeida, Luis Pedro
- Subjects
- *
EROSION , *GRAVEL , *ABSOLUTE sea level change , *GRAVITATIONAL effects , *WATER waves , *WATER levels - Abstract
Pressure on the coastline is escalating due to the impacts of climate change, this is leading to a rise in sea-levels and intensifying storminess. Consequently, many regions of the coast are at increased risk of erosion and flooding. Therefore coastal protection schemes will increase in cost and scale. In response there is a growing use of nature-based coastal protection which aim to be sustainable, effective and adaptable. An example of a nature-based solution is a dynamic cobble berm revetment: a berm constructed from cobble and other gravel sediments at the high tide wave runup limit. These structures limit wave excursion protecting the hinterland from inundation, stabilise the upper beach and adapt to changes in water level. Recent experiments and field applications have shown the suitability of these structures for coastal protection, however many of the processes and design considerations are poorly understood. This study directly compares two prototype scale laboratory experiments which tested dynamic cobble berm revetments constructed with approximately the same geometry but differing gravel characteristics; well-sorted rounded gravel (DynaRev1) and poorly-sorted angular gravel (DynaRev2). In both cases the structures were tested using identical wave forcing including incrementally increasing water level and erosive wave conditions. The results presented in this paper demonstrate that both designs responded to changing water level and wave conditions by approaching a dynamically stable state, where individual gravel is mobilised under wave action but the geometry remains approximately constant. Further, both structures acted to reduce swash excursions compared to a pure sand beach. However, their morphological behaviour is response to wave action varied considerably. Once overtopping of the designed crest occurred, the poorly-sorted revetment developed a peaked crest which grew in elevation as the water level or wave height increased, further limited overtopping. By comparison, the well-sorted revetment was characterised by a larger volume of submerged gravel and a lower elevation flat crest which responded less well to changes in conditions. This occurred due to two processes: (1) for the poorly-sorted case, gravel sorting processes moved small to medium gravel material (D 50 < 70 mm) to the crest and (2) the angular nature of the poorly-sorted gravel material promoted increased interlocking. Both of these processes led to a gravel matrix that is more resistant to wave action and gravitational effects. Both revetments experienced some sinking due to sand erosion beneath the front slope. The rate of sinking for the well-sorted case was larger and continued throughout due to the large pore spaces within the gravel matrix. For the poorly sorted revetment in DynaRev2, sand erosion ceased after approximately 28 h due to the development of a filter layer of small gravel at the sand-gravel interface reducing porosity at this location, hence a larger volume of sand was preserved beneath the structure. Both designs present a low-cost and effective solution for protecting sandy coastlines but from an engineering viewpoint it appears better to avoid well-sorted gravel material and greater gravel angularity has been seen to increase crest stability. • Dynamic cobble berm revetments prevent erosion and protect the hinterland. • Gravel characteristics have a large impact on resultant revetment morphology. • Overtopping drives morphodynamic change in dynamic cobble berm revetments. • Dynamic cobble berm revetments can be adaptable to sea-level rise. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
41. Local values and fairness in climate change adaptation: Insights from marginal rural Australian communities.
- Author
-
Graham, Sonia, Barnett, Jon, Mortreux, Colette, Hurlimann, Anna, and Fincher, Ruth
- Subjects
- *
FAIRNESS , *CLIMATE change , *ABSOLUTE sea level change , *COASTS , *HOMEOWNERS , *RELOCATION - Abstract
A key criterion of successful adaptation to climate change is that it avoids potential inequalities arising from climate impacts or from adaptation strategies themselves. Recent research on adaptation in developing and developed countries argues that the measures of such fairness cannot be captured by standard metrics of vulnerability and should be situated in the milieu of people’s daily lives and temporalities. Yet there is little empirical evidence to support this theoretical argument. This paper describes a method, and presents findings from research that aimed to understand and classify the lived values of four marginal rural communities at risk of sea-level rise in Australia to inform adaptation planning and implementation. Our research finds that there are at least five types of primary residents and second home-owners attached to these four low-lying coastal communities. Some of these residents are more likely to be amenable to relocation if their needs for affordable living and belonging are met. For others, there may be little that can be done to compensate for the loss of place attachment, and implementing a measured approach that provides them time to adapt to the idea of change and form connections to new places is the best that could be achieved. We discuss the implications of place-specific and people-centric values for achieving fair adaptation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
42. Description and assessment of regional sea-level trends and variability from altimetry and tide gauges at the northern Australian coast.
- Author
-
Gharineiat, Zahra and Deng, Xiaoli
- Subjects
- *
ABSOLUTE sea level change , *ALTIMETRY , *SEA level , *OCEAN circulation , *TIME series analysis ,EL Nino - Abstract
This paper aims at providing a descriptive view of the low-frequency sea-level changes around the northern Australian coastline. Twenty years of sea-level observations from multi-mission satellite altimetry and tide gauges are used to characterize sea-level trends and inter-annual variability over the study region. The results show that the interannual sea-level fingerprint in the northern Australian coastline is closely related to El Niño Southern Oscillation (ENSO) and Madden-Julian Oscillation (MJO) events, with the greatest influence on the Gulf Carpentaria, Arafura Sea, and the Timor Sea. The basin average of 14 tide-gauge time series is in strong agreement with the basin average of the altimeter data, with a root mean square difference of 18 mm and a correlation coefficient of 0.95. The rate of the sea-level trend over the altimetry period (6.3 ± 1.4 mm/yr) estimated from tide gauges is slightly higher than that (6.1 ± 1.3 mm/yr) from altimetry in the time interval 1993–2013, which can vary with the length of the time interval. Here we provide new insights into examining the significance of sea-level trends by applying the non-parametric Mann-Kendall test. This test is applied to assess if the trends are significant (upward or downward). Apart from a positive rate of sea-level trends are not statistically significant in this region due to the effects of natural variability. The findings suggest that altimetric trends are not significant along the coasts and some parts of the Gulf Carpentaria (14°S-8°S), where geophysical corrections (e.g., ocean tides) cannot be estimated accurately and altimeter measurements are contaminated by reflections from the land. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
43. Climate-adaptive planning for the long-term resilience of transportation energy infrastructure.
- Author
-
Beheshtian, Arash, Donaghy, Kieran P., Richard Geddes, R., and Oliver Gao, H.
- Subjects
- *
CLIMATE change , *SUPPLY chain management , *RISK aversion , *ABSOLUTE sea level change - Abstract
This paper investigates a long-term planning response to the climate-vulnerability of transportation energy infrastructure in the borough of Manhattan, NY. The proposed model, a two-stage stochastic optimization, features a hybrid utility-regret function with increasing relative and decreasing absolute risk aversion. Modeling results suggest (1) investment in early- and late-stage resilience-enhancing solutions as a complementary approach with significant weight on immediate actions, and (2) a decentralized supply chain formation through an early-stage deployment of reservoir tanks within the case study area. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
44. Use of ecosystems in coastal erosion management.
- Author
-
Gracia, A., Rangel-Buitrago, Nelson, Oakley, Judith A., and Williams, A.T.
- Subjects
ECOSYSTEMS ,COASTAL changes ,ABSOLUTE sea level change ,GABIONS ,ENVIRONMENTAL impact analysis - Abstract
With a global increase in coastal development, together with increasing storminess and continuing sea level rise, coastal erosion has become a serious problem along a significant percentage of coastlines of many countries. Coastal erosion and shoreline management plans are often implemented on an action-reaction and post-disaster basis, resulting in installation of hard engineering structures, such as, groins, seawalls, revetments, gabions and breakwaters. These hard stabilization structures usually alter the natural environment of the coast, producing negative impacts. They do little to work with nature, and sustainability is a currently a critical issue. Under present and future environmental conditions, the world requires smarter coastal protection strategies that are adaptable, sustainable, multi-functional and economically viable to help solve immediate and predicted coastal erosion problems. An ecosystem-based approach based on the creation and restoration of coastal ecosystems, such as wetlands (e.g. mangroves), biogenic reef structures (e.g. corals, oysters, and mussels), seagrass beds and dune vegetation can offer optimal natural alternatives to help solve coastal erosion. Coastal ecosystems have some capacity for self-repair and recovery, and can provide significant advantages over traditional hard engineering approaches against coastal erosion. Also, they play a vital role in reducing the susceptibility of coastal communities to hazards through their multiple roles in processes, including sediment capture, system roughness and thus attenuation of wave energy. This paper seeks to undertake a general review of adaptation and protection measures against coastal erosion issues, based on incorporation of ecology and ecosystem services into coastal erosion management strategies. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
45. MIS 5e relative sea-level changes in the Mediterranean Sea: Contribution of isostatic disequilibrium.
- Author
-
Stocchi, Paolo, Vacchi, Matteo, Lorscheid, Thomas, de Boer, Bas, Simms, Alexander R., van de Wal, Roderik S.W., Vermeersen, Bert L.A., Pappalardo, Marta, and Rovere, Alessio
- Subjects
- *
ABSOLUTE sea level change , *INTERGLACIALS , *ICE sheets , *GLOBAL warming , *GEOMORPHOLOGY - Abstract
Sea-level indicators dated to the Last Interglacial, or Marine Isotope Stage (MIS) 5e, have a twofold value. First, they can be used to constrain the melting of Greenland and Antarctic Ice Sheets in response to global warming scenarios. Second, they can be used to calculate the vertical crustal rates at active margins. For both applications, the contribution of glacio- and hydro-isostatic adjustment (GIA) to vertical displacement of sea-level indicators must be calculated. In this paper, we re-assess MIS 5e sea-level indicators at 11 Mediterranean sites that have been generally considered tectonically stable or affected by mild tectonics. These are found within a range of elevations of 2–10 m above modern mean sea level. Four sites are characterized by two separate sea-level stands, which suggest a two-step sea-level highstand during MIS 5e. Comparing field data with numerical modeling we show that (i) GIA is an important contributor to the spatial and temporal variability of the sea-level highstand during MIS 5e, (ii) the isostatic imbalance from the melting of the MIS 6 ice sheet can produce a >2.0 m sea-level highstand, and (iii) a two-step melting phase for the Greenland and Antarctic Ice Sheets reduces the differences between observations and predictions. Our results show that assumptions of tectonic stability on the basis of the MIS 5e records carry intrinsically large uncertainties, stemming either from uncertainties in field data and GIA models. The latter are propagated to either Holocene or Pleistocene sea-level reconstructions if tectonic rates are considered linear through time. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
46. Probabilistic mapping of storm-induced coastal inundation for climate change adaptation.
- Author
-
Li, Ning, Yamazaki, Yoshiki, Roeber, Volker, Cheung, Kwok Fai, and Chock, Gary
- Subjects
- *
FLOODS , *MATHEMATICAL mappings , *CLIMATE change , *HURRICANES , *ABSOLUTE sea level change - Abstract
This paper describes a probabilistic approach for mapping of coastal flood hazards associated with sea-level rise and storm intensification toward the end of the 21st century. Under the Representative Concentration Pathway (RCP) 8.5, the Coupled Model Intercomparison Project Phase 5 (CMIP5) predicts a 0.6-m ensemble mean of sea-level rise for the Central Pacific from the 1986–2005 to 2081–2100 epochs. Fifty downscaling simulations of the 2080–2099 period from the CMIP5 NCAR-CCSM4 model produce 2492 hurricanes around the Hawaiian Islands. In comparison with a control dataset for the 1980–1999 period, the simulated future hurricanes show a slight increase in number and a northward shift of the tracks toward the Hawaiian Islands. There are 627 hurricanes in the 2080–2099 dataset with potential impact on Oahu, and the top 24 storms selected by wind speed at the urban Honolulu coast define a scenario set for inundation mapping. A suite of spectral wave, circulation, and Boussinesq models in a nested grid system describes generation and propagation of surge and waves across the ocean as well as wave setup and runup at the coast. The interoperable package includes phase-averaged and phase-resolving processes to determine the coastal flood hazards over a range of spatial and temporal scales during a hurricane event. Since the simulated dataset corresponds to a quasi 1000-year period, barring the tail end of the distribution, the suite of inundation scenarios enables definition of flood hazard maps with return periods of up to 500 years or annual exceedance probabilities of 0.2% or greater for climate change adaptation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
47. Evaluating the cascading impacts of sea level rise and coastal flooding on emergency response spatial accessibility in Lower Manhattan, New York City.
- Author
-
Yin, Jie, Lin, Ning, Yu, Dapeng, and Wilby, Robert L.
- Subjects
- *
FLOODS , *ABSOLUTE sea level change , *EMERGENCY medical services , *COASTS - Abstract
This paper describes a scenario-based approach for evaluating the cascading impacts of sea level rise (SLR) and coastal flooding on emergency responses. The analysis is applied to Lower Manhattan, New York City, considering FEMA’s 100- and 500-year flood scenarios and New York City Panel on Climate Change (NPCC2)’s high-end SLR projections for the 2050s and 2080s, using the current situation as the baseline scenario. Service areas for different response timeframes (3-, 5- and 8-min) and various traffic conditions are simulated for three major emergency responders (i.e. New York Police Department (NYPD), Fire Department, New York (FDNY) and Emergency Medical Service (EMS)) under normal and flood scenarios. The modelling suggests that coastal flooding together with SLR could result in proportionate but non-linear impacts on emergency services at the city scale, and the performance of operational responses is largely determined by the positioning of emergency facilities and the functioning of traffic networks. Overall, emergency service accessibility to the city is primarily determined by traffic flow speed. However, the situation is expected to be further aggravated during coastal flooding, with is set to increase in frequency and magnitude due to SLR. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
48. Evolution of the first mouth bar, distributaries and floodplains of the Pearl River Delta.
- Author
-
Xiong, Haixian, Zhang, Zhenghao, Lu, Bangliang, Zong, Yongqiang, and Wu, Jiaxue
- Subjects
- *
FLOODPLAINS , *ABSOLUTE sea level change , *TIDAL forces (Mechanics) , *GEOMORPHOLOGY , *FOSSIL microorganisms , *CARBON isotopes , *WETLANDS - Abstract
As one of the most densely populated areas in the world, the Pearl River delta has been well studied in its postglacial sedimentary stratigraphy and the effects of Holocene sea-level rise. However, the effects of fluvial force on its geomorphological evolution are much less understood. This paper analyzed the Holocene sedimentary archives and reconstructed the geomorphologic history of an area where the West and North Rivers join and enter the deltaic basin. The reconstruction is based on the analyses of particle size, total organic carbon, organic carbon isotope ratios and microfossil diatoms of five radiocarbon-dated core sediments. The results show rapid paleo-incised valley infilling since c. 9500 cal. a BP, in response to sea-level rise. During marine regression starting from c. 8000 cal. a BP, a bifurcation occurred, and a mouth bar was developed. While the mouth bar emerged to mean tide level around c. 5500 cal. a BP, the surrounding estuarine subtidal flats were gradually transformed into tidal wetlands by c. 3000 cal. a BP. The immediate adjacent waters to the mouth bar were gradually infilled from c. 3000 cal. a BP onwards which narrowed the distributary channels. This landform evolution in the head area of the Pearl River delta resulted in the gradually strengthening fluvial force and weakening tidal force since the relative sea level approached its stabilization. During the past 3000 years, the continuous strengthening of fluvial force supported the accretion of deltaic floodplains. The discovery of mouth bar formation, channel narrowing and deltaic floodplain accretion in this location brings a new perspective of scientific investigation to river delta geomorphologic evolution in response to natural and anthropogenic factors. • The first mouth bar and bifurcation of the Pearl River delta are identified. • Geomorphologic evolution of the mouth bar and delta plains are reconstructed. • Strengthening fluvial force played a key role in the development of the delta plain. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. Landscape change and climate attribution, with a case study of estuarine marshes.
- Author
-
Phillips, Jonathan D.
- Subjects
- *
LANDSCAPE changes , *CLIMATE change , *GLOBAL warming , *HURRICANE Florence, 2018 , *ABSOLUTE sea level change - Abstract
Determining effects of climate change on landscapes involves numerous uncertainties. This paper presents and illustrates a protocol for climate attribution of landscape responses. The major steps are ascertaining potential climate-related responses, establishing plausibility for a climatic influence, identifying alternative or additional causes, testing possible climate and non-climate causes, and interpreting the role of climate and climate change in the landscape response. The protocol is based on existing practice in the historical and interpretive branches of Earth and ecological sciences, and explicitly considers negative (non-confirmatory) results for climate and other factors. The protocol is applied to the conversion of brackish marsh to open water in the upper Neuse River estuary, North Carolina. Conversion since at least the mid twentieth century can be attributed to relative sea-level rise, driven primarily by general climate warming, with no supporting evidence for any additional or alternative drivers. The only other factor with supporting evidence is human modification in the form of ditches, around which conversion was concentrated, though marsh loss also occurred in unditched portions. Rapid recent marsh loss is attributable to Hurricane Florence (2018), particularly the storm surge. Weak positive inferential support exists for a role of climate change in the storm, but aspects of the storm's impact not linked to climate are more important for the marsh conversions. Overall, the landscape response can be linked to climate, exacerbated by direct human impacts of marsh ditching, and strongly influenced by local place factors and the specific storm track. Recent and ongoing climate change is a significant factor, but not paramount, in determining the landscape response. The Neuse River case study is not unusual—and is probably typical—in identifying a combination of climate and other factors strongly influencing landscape response. [Display omitted] • Attributing landscape responses to climate change presents numerous complexities. • Landscape response attribution protocol based on traditional geomorphic approaches • LRA protocol applied to recent conversion of estuarine marsh to open water • Marsh loss due to sea-level rise & major storm, but non-climate factors important • LRA protocol useful to identify & evaluate climate & non-climate drivers of change [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. Identifying barriers and potentials of integrated assessments of sustainable urban development and adaptation to rising sea levels.
- Author
-
Lea Eggert, Anna, Löwe, Roland, and Arnbjerg-Nielsen, Karsten
- Subjects
- *
SUSTAINABLE urban development , *PHYSIOLOGICAL adaptation , *SUSTAINABILITY , *SEA level , *ABSOLUTE sea level change , *URBAN growth , *STRUCTURAL frames - Abstract
• Review of indicator frameworks for urban sustainability and coastal adaptation. • Comparison of frameworks and analysis of differences and similarities. • Consistency among sustainability frameworks; ambiguities in coastal adaptation. • Varying scopes of city functions and risk create barriers to integrated assessment. • Integrated assessments can obviate unintended consequences and foster synergies. Current adaptation responses to sea-level rise tend to focus on protecting existing infrastructure resulting in unsustainable adaptation pathways. At the same time, urban development compromises a city's adaptive capacity if the climate risk component is ignored. While fighting for the same space, these two domains are currently widely analyzed separately. This paper develops a framework for integrating sustainability assessments of sustainable urban development (SUD) and coastal adaptation to climate change (CACC). Through a systematic literature review, we collected more than 2,700 indicators for SUD and 1,800 indicators for CACC. The indicators occurring most frequently are extracted and structured into frameworks. The study highlights the differences and similarities between the two frameworks. We further identify complementary and conflicting objectives that can advance or inhibit the effective integration of SUD and CACC. CACC tends to focus on assessing specific adaptation measures and their immediate impact on the city's vulnerability, ignoring wider impacts on socioeconomic systems. SUD considers the city and its functions as a whole but ignores vulnerability assessments across urban subsystems. We develop a combined framework for sustainability assessment that may serve as a basis for both qualitative and quantitative integrated studies under the paradigm of sustainable adaptation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.