Pan European coastal vulnerability: developing a new coastal behaviour data product, EMODnet Geology.

The identification and communication of potential risks faced by coastal-zone populations is becoming increasingly important to strengthen society’s resilience and enable communities to better handle coastal hazards. Assessing risk and vulnerability is important to inform the public, as well as coastal managers, on sustainable policy and practice. This so-called coastal vulnerability has been assessed, quantified and mapped using a wide variety of approaches, focussing on hazard, risk and resilience. Many studies place emphasis on physical parameters such as geology and topography, and on marine factors such as wave energy and storm frequency. Others also incorporate socio-economic factors such as population, cultural heritage, presence of crucial infrastructure, land use and conservation status.Our pan-European assessment of coastal vulnerability adds a new layer of information to the existing EMODnet Geology product suite on shoreline change. Using the most complete inventory to date of case studies on coastal vulnerability in scientific journals, books and governmental reports, we have developed a detailed database on various vulnerability aspects across Europe and in other countries around the world. By geo-locating the maps from these studies, we have been able to assess the extent of coverage of coastal vulnerability assessment around European shorelines. Drawing on the existing literature, we have developed a common legend, indicating lower, intermediate and higher levels of vulnerability mapped at a pan-European scale.Our research indicates incomplete coverage by existing studies, highlighting the potential to use data from existing EMODnet products such as shoreline migration, geology and bathymetry, to develop a basic coastal vulnerability index that can be validated against existing studies and used to fill the gaps. The resulting applied data product will help raise awareness in the general public and facilitate the work of coastal policy makers, planners and practitioners.<br/

Estimation of abrasion on flint shingle beaches in East Sussex, UK.

In situ abrasion of shingle beach material is a neglected area of study in coastal geomorphology, with reduction in beach volumes normally attributed to longshore and offshore drift. Results from field abrasion experiments conducted on flint shingle beaches on the East Sussex coast, southern England, show that in situ reductions in volume of beach material may be more significant than has been thought. Two beaches composed almost entirely of flint shingle were seeded with hard quartzite from a Devon beach and less resistant limestone from a South Wales beach that are readily distinguishable from the flint. The seeding commenced in January 2001. The pebbles, similar in size and shape to the natural flint shingle, were left in the surf zone at two sites. Prior to exposure the pebbles were engraved with a code number and weighed. At regular intervals those that could be re-found were re-weighed and returned to the beach. Abrasion rates were calculated for each pebble as percentage weight loss per tide. By the end of October 2001, more than 700 measurements of abrasion rates had been made from a total of 431 pebbles. Average limestone abrasion rates (0.0266% loss of weight per tide) were three times greater than those of quartzite (0.0082% per tide). Measurable abrasion rates were recorded over just a few tidal cycles, not only in severe wave conditions but also in much calmer weather. The maximum abrasion rates recorded exceeded 1% per tide for limeston

Socio-Economic Resilience to Floods in Coastal Areas of Thailand

Krabi and Nakhon Si Thammarat are two coastal provinces in Thailand facing substantial threats from climate change induced hydrometeorological hazards, including enhanced coastal erosion and flooding. Human populations and livelihoods in these coastal provinces are at greater risk than those in inland provinces. However, little is known about the communities’ resilience and coping capacities regarding hydrometeorological hazards of varying magnitudes. The study conducted a quantitative socio-economic assessment of how people in Krabi and Nakhon Si Thammarat provinces manage and respond to hydrometeorological hazards, examining their resilience and coping capacities. This was a cross-sectional study based on secondary data collection on the social and economic dimensions of resilience, and a review of literature on coping mechanisms to hydrometeorological hazards within the study area. Measuring and mapping socio-economic resilience was based on the available data gathered from the social and economic dimensions, with existing or standard indicators on exposure and vulnerability applied uniformly across subdistricts. A combination of social and economic dimensions produced novel socio-economic resilience index scores by subdistrict, which were mapped accordingly for the two coastal provinces. The study also derived a coping capacity index scores by combining availability of skills or soft capacity and availability of structural resources or hard coping capacity. Socio-economic resilience index scores varied greatly amongst subdistricts. Combining the soft and hard coping capacities, the average score across districts in both provinces was 3 out of a possible 4, meaning that most of the districts were largely resilient. However, variations also existed by subdistrict. Few subdistricts in both Krabi and Nakhon Si Thammarat provinces had low coping capacity index scores between 1 and 2 out of 4. District averages of socio-economic resilience scores mask the variations at subdistrict level. More studies with rigorous methodologies at village or neighborhood level is needed to obtain a nuanced understanding of community resilience to hydrometeorological hazards

Coastal Erosion and Flood Coping Mechanisms in Southern Thailand: A Qualitative Study

Communities in coastal regions are affected by the impacts of extreme climatic events causing flooding and erosion. Reducing the impacts of flood and erosion in these areas by adopting coping strategies that fortify the resilience of individuals and their localities is desirable. This study used summative content analysis to explore the coping mechanisms of coastal communities before, during, and after various dangers relating to flooding and erosion. The findings from the study show that effective surveillance systems, disaster preparedness, risk mapping, early warning systems, availability of databases and functional command systems, as well as reliable funding are essential to efficiently cope with hazards of coastal flooding and erosion. As flooding and erosion have been predicted to be more severe due to climate change in the coming years, the adoption of effective natural and artificial mechanisms with modern technologies could help coastal regions to be more resilient in coping with the dangers associated with flooding and erosion. Pragmatic policies and programs to this end by actors are critical to averting crises induced by flooding and erosion in coastal areas

Chalk cliff retreat in East Sussex and Kent 1870s to 2001

The retreat of chalk cliffs fringing the eastern English Channel contributes shingle to the beaches which helps to protect the cliffs and slow down erosion. Conversely, cliff retreat endangers settlements and infrastructure on the clifftop. Rates of retreat have been calculated by a variety of methods over the past century, but no attempt has been made to provide a complete coverage that allows for a true comparison of retreat rates over the entire coastline. Using historic maps and recent orthophotos, cliff retreat rates have been calculated for consecutive 50 m sections of chalk cliff along the English side of the entire eastern English Channel for a period of 125 years. The chalk cliffs of East Sussex erode at an average rate of 0.25 - 0.3 m y−1 while those in Kent at a rate of 0.1 m y−1

Soft copy photogrammetry to measure shore platform erosion on decadal time scales

Shore platform erosion is considered a driving mechanism for cliff recession on many rocky coasts and, in the vicinity of sea defence structures, a threat to their stability, yet the spatial pattern of platform erosion, as well as the rate of lowering, is poorly documented. Measurements based on techniques such as the micro-erosion metre or laser scanner, though highly accurate for short time scales and specific locations, are difficult to extrapolate in space and time. They also fail to record meso-scale changes such as block removal. This paper describes a technique to quantify spatial and temporal changes and presents first results

Observations on coastal biokarst, Hells Gate, Lord Howe Island, Australia

No description supplie

Field rock block exposure trials

The exposure of rock blocks to monitor environmental controls on rock weathering and erosion processes and rates has become an established technique in geomorphology. Such exposure trials using rock blocks, ranging in size from discs of diameter 20 mm and 5 mm thickness to large blocks of dimensions 200 mm x 200 mm x 200 mm, are used to examine weathering and erosion rates over a variety of different spatial and temporal scales. This paper discusses the original design and purpose of rock block exposures and the range of environments in which they have been used. Subsequent modifications of the original technique have been used to measure not just erosion rates, but also rates of accumulation of travertine, rates of solute uptake and to monitor rock surface temperature changes. Two examples are given of field trials in which weathering gradients have been determined using a range of rock block exposure types. Little research has been carried out to correlate weathering and erosion rates determined from rock tablet exposure and other techniques, though one study suggests that there is an order of magnitude difference between solution rates measured using this technique and water hardness methods. Rock blocks, however, are often used to give a more detailed picture of spatial and temporal variations in weathering and erosion rates that would otherwise be masked by such indirect mass balance approaches