53 research outputs found
Application of flood risk modelling in a web-based geospatial decision support tool for coastal adaptation to climate change
This is the discussion paper that was under review for the for the journal Natural Hazards and Earth
System Sciences (NHESS).The final paper is available from the publisher via DOI: 10.5194/nhess-15-1457-2015A pressing problem facing coastal decision makers
is the conversion of “high-level” but plausible climate
change assessments into an effective basis for climate change
adaptation at the local scale. Here, we describe a web-based,
geospatial decision support tool (DST) that provides an assessment
of the potential flood risk for populated coastal
lowlands arising from future sea-level rise, coastal storms,
and high river flows. This DST has been developed to support
operational and strategic decision making by enabling
the user to explore the flood hazard from extreme events,
changes in the extent of the flood-prone areas with sea-level
rise, and thresholds of sea-level rise where current policy and
resource options are no longer viable. The DST is built in an
open-source GIS that uses freely available geospatial data.
Flood risk assessments from a combination of LISFLOODFP
and SWAB (Shallow Water And Boussinesq) models are
embedded within the tool; the user interface enables interrogation
of different combinations of coastal and river events
under rising-sea-level scenarios. Users can readily vary the
input parameters (sea level, storms, wave height and river
flow) relative to the present-day topography and infrastructure
to identify combinations where significant regime shifts
or “tipping points” occur. Two case studies demonstrate the
attributes of the DST with respect to the wider coastal community
and the UK energy sector. Examples report on the assets
at risk and illustrate the extent of flooding in relation to
infrastructure access. This informs an economic assessment
of potential losses due to climate change and thus provides
local authorities and energy operators with essential information
on the feasibility of investment for building resilience
into vulnerable components of their area of responsibilit
CONTEMPORARY SALT-MARSH FORAMINIFERAL DISTRIBUTION FROM THE ADRIATIC COAST OF CROATIA AND ITS POTENTIAL FOR SEA-LEVEL STUDIES
Salt-marsh foraminifera serve as proxy sea-level indicators due to a quantifiable relationship with elevation in the contemporary environment. In this paper, we document the distribution of salt-marsh foraminifera from two microtidal sites, Jadrtovac and Blace, along the Adriatic coast of Croatia and assess their suitability as proxies for elevation in transfer-function-based reconstructions of sea level, which has so far evaded the Mediterranean region. The assemblages are dominated by typical salt-marsh agglutinated taxa, Jadammina macrescens and Trochammina inflata, and the calcareous taxa Ammonia spp. and Quinqueloculina spp. Quantitative analyses revealed that the assemblages are divided into three faunal zones, which are elevation dependent, and where an assemblage dominated by J. macrescens and T. inflata extends to higher elevations in the intertidal frame. The training set was used to develop a tidal- level transfer function using linear regression due to the short environmental gradients observed. The model predicts sea level with a precision of ± 0.08 m. This study highlights the strong potential of salt-marsh foraminifera in reconstructing RSL trends for the Mediterranean region, where studies of past sea-level have previously been restricted to other indicators
Dynamic interactions between coastal storms and salt marshes: A review
This manuscript reviews the progresses made in the understanding of the dynamic interactions between coastal storms and salt marshes, including the dissipation of extreme water levels and wind waves across marsh surfaces, the geomorphic impact of storms on salt marshes, the preservation of hurricanes signals and deposits into the sedimentary records, and the importance of storms for the long term survival of salt marshes to sea level rise. A review of weaknesses, and strengths of coastal defences incorporating the use of salt marshes including natural, and hybrid infrastructures in comparison to standard built solutions is then presented.
Salt marshes are effective in dissipating wave energy, and storm surges, especially when the marsh is highly elevated, and continuous. This buffering action reduces for storms lasting more than one day. Storm surge attenuation rates range from 1.7 to 25 cm/km depending on marsh and storms characteristics. In terms of vegetation properties, the more flexible stems tend to flatten during powerful storms, and to dissipate less energy but they are also more resilient to structural damage, and their flattening helps to protect the marsh surface from erosion, while stiff plants tend to break, and could increase the turbulence level and the scour. From a morphological point of view, salt marshes are generally able to withstand violent storms without collapsing, and violent storms are responsible for only a small portion of the long term marsh erosion.
Our considerations highlight the necessity to focus on the indirect long term impact that large storms exerts on the whole marsh complex rather than on sole after-storm periods. The morphological consequences of storms, even if not dramatic, might in fact influence the response of the system to normal weather conditions during following inter-storm periods. For instance, storms can cause tidal flats deepening which in turn promotes wave energy propagation, and exerts a long term detrimental effect for marsh boundaries even during calm weather. On the other hand, when a violent storm causes substantial erosion but sediments are redistributed across nearby areas, the long term impact might not be as severe as if sediments were permanently lost from the system, and the salt marsh could easily recover to the initial state
Tectonic influences on late Holocene relative sea levels from the central-eastern Adriatic coast of Croatia
Differential tectonic activity is a key factor responsible for variable relative sea-level (RSL) changes during the late Holocene in the Adriatic. Here, we compare reconstructions of RSL from the central-eastern Adriatic coast of Croatia with ICE-7G_NA (VM7) glacial-isostatic model RSL predictions to assess underlying driving mechanisms of RSL change during the past ∼ 2700 years. Local standardized published sea-level index points (n = 23) were combined with a new salt-marsh RSL reconstruction and tide-gauge measurements. We enumerated fossil foraminifera from a short salt-marsh sediment core constrained vertically by modern foraminiferal distributions, and temporally by radiometric analyses providing sub-century resolution within a Bayesian age-depth framework. We modelled changes in RSL using an Errors-In-Variables Integrated Gaussian Process (EIV-IGP) model with full consideration of the available uncertainty. Previously established index points show RSL rising from −1.48 m at 715 BCE to −1.05 m by 100 CE at 0.52 mm/yr (−0.82-1.87 mm/yr). Between 500 and 1000 CE RSL was −0.7 m below present rising to −0.25 m at 1700 CE. RSL rise decreased to a minimum rate of 0.13 mm/yr (−0.37-0.64 mm/yr) at ∼1450 CE. The salt-marsh reconstruction shows RSL rose ∼0.28 m since the early 18th century at an average rate of 0.95 mm/yr. Magnitudes and rates of RSL change during the twentieth century are concurrent with long-term tide-gauge measurements, with a rise of ∼1.1 mm/yr. Predictions of RSL from the ICE-7G_NA (VM7) glacial-isostatic model (−0.25 m at 715 BCE) are consistently higher than the reconstruction (−1.48 m at 715 BCE) during the Late Holocene suggesting a subsidence rate of 0.45 ± 0.6 mm/yr. The new salt-marsh reconstruction and regional index points coupled with glacial-isostatic and statistical models estimate the magnitude and rate of RSL change and subsidence caused by the Adriatic tectonic framework. © 2018 Elsevier Lt
A coastal vulnerability assessment for planning climate resilient infrastructure
publisher: Elsevier articletitle: A coastal vulnerability assessment for planning climate resilient infrastructure journaltitle: Ocean & Coastal Management articlelink: https://doi.org/10.1016/j.ocecoaman.2018.06.007 content_type: article copyright: © 2018 The Authors. Published by Elsevier Ltd
Phase 1b randomized, double-blind study of namilumab, an anti-granulocyte macrophage colony-stimulating factor monoclonal antibody, in mild-to-moderate rheumatoid arthritis
Change from baseline in swollen (a) and tender (b) joint counts. *Error bars show upper SE for placebo and lower SE for namilumab. SE standard error, SJC swollen joint count, TJC tender joint count. (PDF 1292 kb
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