A biological indicator for measuring and communicating local sea level rise captured in historic photographs.

Abstract This paper explores a novel approach to collecting and communicating local site-specific data on recent sea level rise (SLR) using black zone biotic levels left on historic coastal stone structures by a stable community of cyanobacteria (blue-green algae) at the Royal Naval Dockyard in Bermuda. Photographs taken at the Dockyard in 1870, 2007 and 2017 show an upward shift in this living cyanobacterial community. A spatio-temporal digital twin computed from historic and contemporary photo assets was created to test the viability of these black zone lines as a proxy for sea level rise (SLR) measurements in Bermuda. Shifts in these black zone lines when analyzed through the digital twin demonstrate an average upward shift of 2.2 mm per year between 1870 and 2007 and 2.7 mm per year between 1870 and 2017, somewhat lower than the Global estimates from the Intergovernmental Panel on Climate Change Assessment Report predictions. However, the digital twin showed a dramatic upward shift of 8.8 cm between 2007 and 2017, or 8.8 mm per year, which coincided with Bermuda's highest recorded tidal extent since 1932. Black zone cyanobacteria are highly SLR sensitive and over long time scales comparative imagery of black zones could present a proper indicator of average sea level rise. At timescales less than 10 years the black zone may be best indicative of episodic tidal extent. As SLR will continue to shift supralittoral cyanobacteria upwards in Bermuda and in warm rocky intertidal zones worldwide, tidal monitoring and black zone assessments may prove to be a useful combination in documenting and communicating the reality, extent and possible acceleration of local SLR.

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Depositional setting and limiting factors of early Late Cretaceous glaucony formation: implications from Cenomanian glauconitic strata (Elbtal Group, Germany)

Facies ◽

10.1007/s10347-021-00627-y ◽

2021 ◽

Vol 67 (3) ◽

Author(s):

Markus Wilmsen ◽

Udita Bansal

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Time Scales ◽

Late Cretaceous ◽

Limiting Factors ◽

High Accumulation ◽

Spatio Temporal ◽

Facies Types ◽

Facies Succession ◽

Early Late

AbstractCenomanian strata of the Elbtal Group (Saxony, eastern Germany) reflect a major global sea-level rise and contain, in certain intervals, a green authigenic clay mineral in abundance. Based on the integrated study of five new core sections, the environmental background and spatio-temporal patterns of these glauconitic strata are reconstructed and some general preconditions allegedly needed for glaucony formation are critically questioned. XRD analyses of green grains extracted from selected samples confirm their glauconitic mineralogy. Based on field observations as well as on the careful evaluation of litho- and microfacies, 12 glauconitc facies types (GFTs), broadly reflecting a proximal–distal gradient, have been identified, containing granular and matrix glaucony of exclusively intrasequential origin. When observed in stratigraphic succession, GFT-1 to GFT-12 commonly occur superimposed in transgressive cycles starting with the glauconitic basal conglomerates, followed up-section by glauconitic sandstones, sandy glauconitites, fine-grained, bioturbated, argillaceous and/or marly glauconitic sandstones; glauconitic argillaceous marls, glauconitic marlstones, and glauconitic calcareous nodules continue the retrogradational fining-upward trend. The vertical facies succession with upwards decreasing glaucony content demonstrates that the center of production and deposition of glaucony in the Cenomanian of Saxony was the nearshore zone. This time-transgressive glaucony depocenter tracks the regional onlap patterns of the Elbtal Group, shifting southeastwards during the Cenomanian 2nd-order sea-level rise. The substantial development of glaucony in the thick (60 m) uppermost Cenomanian Pennrich Formation, reflecting a tidal, shallow-marine, nearshore siliciclastic depositional system and temporally corresponding to only ~ 400 kyr, shows that glaucony formation occurred under wet, warm-temperate conditions, high accumulation rates and on rather short-term time scales. Our new integrated data thus indicate that environmental factors such as great water depth, cool temperatures, long time scales, and sediment starvation had no impact on early Late Cretaceous glaucony formation in Saxony, suggesting that the determining factors of ancient glaucony may be fundamentally different from recent conditions and revealing certain limitations of the uniformitarian approach.

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Greenland ice sheet contribution to sea level rise during the last interglacial period: a modelling study driven and constrained by ice core data

Climate of the Past ◽

10.5194/cp-9-353-2013 ◽

2013 ◽

Vol 9 (1) ◽

pp. 353-366 ◽

Cited By ~ 42

Author(s):

A. Quiquet ◽

C. Ritz ◽

H. J. Punge ◽

D. Salas y Mélia

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Interglacial Period ◽

Last Interglacial ◽

Intergovernmental Panel ◽

Orbital Configuration ◽

Global Sea Level

Abstract. As pointed out by the forth assessment report of the Intergovernmental Panel on Climate Change, IPCC-AR4 (Meehl et al., 2007), the contribution of the two major ice sheets, Antarctica and Greenland, to global sea level rise, is a subject of key importance for the scientific community. By the end of the next century, a 3–5 °C warming is expected in Greenland. Similar temperatures in this region were reached during the last interglacial (LIG) period, 130–115 ka BP, due to a change in orbital configuration rather than to an anthropogenic forcing. Ice core evidence suggests that the Greenland ice sheet (GIS) survived this warm period, but great uncertainties remain about the total Greenland ice reduction during the LIG. Here we perform long-term simulations of the GIS using an improved ice sheet model. Both the methodologies chosen to reconstruct palaeoclimate and to calibrate the model are strongly based on proxy data. We suggest a relatively low contribution to LIG sea level rise from Greenland melting, ranging from 0.7 to 1.5 m of sea level equivalent, contrasting with previous studies. Our results suggest an important contribution of the Antarctic ice sheet to the LIG highstand.

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Multivariate spatio-temporal modelling for assessing Antarctica's present-day contribution to sea-level rise

Environmetrics ◽

10.1002/env.2323 ◽

2015 ◽

Vol 26 (3) ◽

pp. 159-177 ◽

Cited By ~ 12

Author(s):

Andrew Zammit-Mangion ◽

Jonathan Rougier ◽

Nana Schön ◽

Finn Lindgren ◽

Jonathan Bamber

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Temporal Modelling ◽

Spatio Temporal

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Spatio-temporal decomposition of geophysical signals in North America

10.5194/egusphere-egu2020-16232 ◽

2020 ◽

Author(s):

Aoibheann Brady ◽

Jonathan Rougier ◽

Bramha Dutt Vishwakarma ◽

Yann Ziegler ◽

Richard Westaway ◽

...

Keyword(s):

North America ◽

Sea Level Rise ◽

Sea Level ◽

Global Scale ◽

Bayesian Hierarchical ◽

Isostatic Adjustment ◽

Modelling Framework ◽

Vertical Land Motion ◽

Early Results ◽

Spatio Temporal

<p>Sea level rise is one of the most significant consequences of projected future changes in climate. One factor which influences sea level rise is vertical land motion (VLM) due to glacial isostatic adjustment (GIA), which changes the elevation of the ocean floor. Typically, GIA forward models are used for this purpose, but these are known to vary with the assumptions made about ice loading history and Earth structure. In this study, we implement a Bayesian hierarchical modelling framework to explore a data-driven VLM solution for North America, with the aim of separating out the overall signal into its GIA and hydrology (mass change) components. A Bayesian spatio-temporal model is implemented in INLA using satellite (GRACE) and in-situ (GPS) data as observations.&#160;Under the assumption that GIA varies in space but is constant in time, and that hydrology is both spatially- and temporally-variable, it is possible to separate the contributions of each component with an associated uncertainty level. Early results will be presented. Extensions to the BHM framework to investigate sea level rise at the global scale, such as the inclusion of additional processes and incorporation of increased volumes of data, will be discussed.</p>

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Ice sheet mass balance and sea level

Antarctic Science ◽

10.1017/s0954102009990137 ◽

2009 ◽

Vol 21 (5) ◽

pp. 413-426 ◽

Cited By ~ 58

Author(s):

I. Allison ◽

R.B. Alley ◽

H.A. Fricker ◽

R.H. Thomas ◽

R.C. Warner

Keyword(s):

Mass Balance ◽

Sea Level Rise ◽

Sea Level ◽

Average Rate ◽

Ice Sheets ◽

Ice Sheet ◽

Measurement Technology ◽

Satellite Gravity ◽

Intergovernmental Panel ◽

Ice Sheet Mass Balance

AbstractDetermining the mass balance of the Greenland and Antarctic ice sheets (GIS and AIS) has long been a major challenge for polar science. But until recent advances in measurement technology, the uncertainty in ice sheet mass balance estimates was greater than any net contribution to sea level change. The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (AR4) was able, for the first time, to conclude that, taken together, the GIS and AIS have probably been contributing to sea level rise over the period 1993–2003 at an average rate estimated at 0.4 mm yr-1. Since the cut-off date for work included in AR4, a number of further studies of the mass balance of GIS and AIS have been made using satellite altimetry, satellite gravity measurements and estimates of mass influx and discharge using a variety of techniques. Overall, these studies reinforce the conclusion that the ice sheets are contributing to present sea level rise, and suggest that the rate of loss from GIS has recently increased. The largest unknown in the projections of sea level rise over the next century is the potential for rapid dynamic collapse of ice sheets.

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Assessment of island beach erosion due to sea level rise: the case of the Aegean archipelago (Eastern Mediterranean)

Natural Hazards and Earth System Science ◽

10.5194/nhess-17-449-2017 ◽

2017 ◽

Vol 17 (3) ◽

pp. 449-466 ◽

Cited By ~ 20

Author(s):

Isavela N. Monioudi ◽

Adonis F. Velegrakis ◽

Antonis E. Chatzipavlis ◽

Anastasios Rigos ◽

Theophanis Karambas ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Spatial Information ◽

Eastern Mediterranean ◽

Sediment Supply ◽

Coastal Development ◽

Beach Erosion ◽

Coastal Protection ◽

Intergovernmental Panel ◽

Economic Resource

Abstract. The present contribution constitutes the first comprehensive attempt to (a) record the spatial characteristics of the beaches of the Aegean archipelago (Greece), a critical resource for both the local and national economy, and (b) provide a rapid assessment of the impacts of the long-term and episodic sea level rise (SLR) under different scenarios. Spatial information and other attributes (e.g., presence of coastal protection works and backshore development) of the beaches of the 58 largest islands of the archipelago were obtained on the basis of remote-sensed images available on the web. Ranges of SLR-induced beach retreats under different morphological, sedimentological and hydrodynamic forcing, and SLR scenarios were estimated using suitable ensembles of cross-shore (1-D) morphodynamic models. These ranges, combined with empirically derived estimations of wave run-up induced flooding, were then compared with the recorded maximum beach widths to provide ranges of retreat/erosion and flooding at the archipelago scale. The spatial information shows that the Aegean pocket beaches may be particularly vulnerable to mean sea level rise (MSLR) and episodic SLRs due to (i) their narrow widths (about 59 % of the beaches have maximum widths < 20 m), (ii) their limited terrestrial sediment supply, (iii) the substantial coastal development and (iv) the limited existing coastal protection. Modeling results indeed project severe impacts under mean and episodic SLRs, which by 2100 could be devastating. For example, under MSLR of 0.5 m – representative concentration pathway (RCP) 4.5 of the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate change (IPCC) – a storm-induced sea level rise of 0.6 m is projected to result in a complete erosion of between 31 and 88 % of all beaches (29–87 % of beaches are currently fronting coastal infrastructure and assets), at least temporarily. Our results suggest a very considerable risk which will require significant effort, financial resources and policies/regulation in order to protect/maintain the critical economic resource of the Aegean archipelago.

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Adaptive Capacity Mapping of Semarang Offshore Territory by the Increasing of Water Level and Climate Change

Forum Geografi ◽

10.23917/forgeo.v27i1.5084 ◽

2013 ◽

Vol 27 (1) ◽

pp. 81

Author(s):

Ifan Ridlo Suhelm

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Adaptive Capacity ◽

Sea Level ◽

Land Subsidence ◽

Educational Background ◽

Intergovernmental Panel ◽

Two Factors ◽

The Face ◽

The Village

Tidal inundation, flood and land subsidence are the problems faced by Semarang city related to climate change. Intergovernmental Panel on Climate Change (IPCC) predicted the increase of sea level rise 18-59 cm during 1990-2100 while the temperature increase 0,6°C to 4°C during the same period. The Semarang coastal city was highly vulnerable to sea level rise and it increased with two factors, topography and land subsidence. The purpose of this study was to map the adaptive capacity of coastal areas in the face of the threat of disasters caused by climate change. The parameters used are Network Number, Employee based educational background, Source Main Livelihoods, Health Facilities, and Infrastructure Road. Adaptive capacity of regions classified into 3 (three) classes, namely low, medium and high. The results of the study showed that most of the coastal area of Semarang have adaptive capacities ranging from low to moderate, while the village with low capacity totaling 58 villages (58.62%) of the total coastal district in the city of Semarang.

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Future sea-level rise drives rocky intertidal habitat loss and benthic community change

PeerJ ◽

10.7717/peerj.9186 ◽

2020 ◽

Vol 8 ◽

pp. e9186 ◽

Cited By ~ 1

Author(s):

Nikolas J. Kaplanis ◽

Clinton B. Edwards ◽

Yoan Eynaud ◽

Jennifer E. Smith

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Large Scale ◽

Environmental Changes ◽

Community Change ◽

Rocky Intertidal ◽

Areal Extent ◽

Intertidal Habitat ◽

Large Area ◽

Habitat Area

The impacts of sea-level rise (SLR) are likely to be the greatest for ecosystems that exist at the land-sea interface, where small changes in sea-level could result in drastic changes in habitat availability. Rocky intertidal ecosystems possess a number of characteristics which make them highly vulnerable to changes in sea-level, yet our understanding of potential community-scale responses to future SLR scenarios is limited. Combining remote-sensing with in-situ large-area imaging, we quantified habitat extent and characterized the biological community at two rocky intertidal study locations in California, USA. We then used a model-based approach to estimate how a range of SLR scenarios would affect total habitat area, areal extent of dominant benthic space occupiers, and numerical abundance of invertebrates. Our results suggest that SLR will reduce total available rocky intertidal habitat area at our study locations, leading to an overall decrease in areal extent of dominant benthic space occupiers, and a reduction in invertebrate abundances. As large-scale environmental changes, such as SLR, accelerate in the next century, more extensive spatially explicit monitoring at ecologically relevant scales will be needed to visualize and quantify their impacts to biological systems.

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Assessment of the Coastal Vulnerability to the Ongoing Sea Level Rise for the Exquisite Rhodes Island (SE Aegean Sea, Greece)

Water ◽

10.3390/w13162169 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2169

Author(s):

Dimitrios Vandarakis ◽

Ioannis P. Panagiotopoulos ◽

Vassiliki Loukaidi ◽

Georgios-Angelos Hatiris ◽

Paraskevi Drakopoulou ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Private Property ◽

Aegean Sea ◽

Vulnerability Index ◽

Coastal Vulnerability ◽

Intergovernmental Panel ◽

Physical Impact ◽

Global Sea Level ◽

Natural Losses

The foreseeable acceleration of global sea level rise could potentially pose a major threat to the natural charm and functional integrity of the world-renowned tourist coastal attractions of Rhodes Island, as a result of the anticipated increasing frequency of flooding and erosion events. Hence, this study aims to determine the most vulnerable segments (in terms of physical impact) of the Rhodes coastline through the widely accepted coastal vulnerability index (CVI), applying a combination of well-known, broadly used approaches and methods. The frequency distribution of the current CVI along the island’s coastline suggests a rather worrying high to very high vulnerability of 40%. In addition, a CVI projection to the end of the 21st century (based on the Intergovernmental Panel on Climate Change predictive scenarios) indicates an enhancement of the total vulnerability by 48%, mainly focused on the majority of the western coastline. Hence, a considerable number of popular coastal destinations in the island shall remain under unignorable threat and, therefore, coastal managers and decision-makers need to hatch an integrated plan to minimize economic and natural losses, private property damage and tourism infrastructure deterioration from flooding and erosion episodes, which will most likely be intensified in the future.

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Beach nourishment versus sea level rise on Florida’s coasts

Shore & Beach ◽

10.34237/1008821 ◽

2020 ◽

pp. 3-13

Author(s):

James Houston

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

East Coast ◽

Beach Nourishment ◽

Shoreline Change ◽

Intergovernmental Panel ◽

Shoreline Changes ◽

The Past ◽

Equilibrium Profile ◽

And Sea Level

Beach nourishment and sea level rise will dominate future shoreline changes on Florida’s 665 miles of sandy coast. Shoreline changes from 2020-2100 are projected along this entire coast using equilibrium profile theory that accurately predicted shoreline changes on Florida’s east coast from 1970-2017 (Houston 2019). Projections for 2020- 2100 are made assuming past rates of beach nourishment for the 30-yr period from 1988-2017 will continue and sea level will rise according to recent projections of the Intergovernmental Panel on Climate Change (IPCC) that include the latest knowledge on ice melting in Antarctica (IPCC 2019). Using the beach nourishment and sea level rise data, equilibrium profile theory is then used to predict shoreline change from 2020-2100 for each IPCC sea level rise projection. Beach nourishment is shown to produce shoreline advance seaward on average for all IPCC scenarios for both the entire Florida coast and east coast and for all scenarios except the upper confidence level of the worst scenario for the southwest and Panhandle coasts. Some of the 30 counties on these coasts will require a greater rate of nourishment than in the past to offset sea level rise for some or all of the scenarios, whereas some will offset sea level rise for all scenarios with lower nourishment rates than in the past. The annual beach nourishment volume for which a county has a shortfall or surplus in offsetting sea level rise for each IPCC scenario can be calculated with the information provided and examples are presented. The approach can be used on coasts outside Florida if beach nourishment and sea level rise are expected to dominate future shoreline change.

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