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This paper examines the vulnerability to flooding and erosion of four open beach study sites in Europe. A framework for the quantitative estimation of present and future coastal flood and erosion risks is established using methods, data and tools from across a range of disciplines, including topographic and bathymetric data, climate data from observation, hindcast and model projections, statistical modelling of current and future climates and integrated risk analysis tools. Uncertainties in the estimation of future coastal system dynamics are considered, as are the consequences for the inland systems. Different implementations of the framework are applied to the study sites which have different wave, tidal and surge climate conditions. These sites are: Santander, Spain—the Atlantic Ocean; Bellocchio, Italy—the Adriatic Sea; Varna, Bulgaria—the Black Sea; and the Teign Estuary, UK—the northern Atlantic Ocean. The complexity of each system is first simplified by sub-division into coastal “impact units” defined by homogeneity in the local key forcing parameters: wave, wind, tide, river discharge, run-off, etc. This reduces the simulation to that of a number of simpler linear problems which are treated by applying the first two components of the Source–Pathway–Receptor–Consequence (S–P–R–C) approach. The case studies reveal the flexibility of this approach, which is found useful for the rapid assessment of the risks of flooding and erosion for a range of scenarios and the likely effectiveness of flood defences

Leymus racemosus (Lam.) Tzvelev subsp. sabulosus (M. Bieb.) Tzvelev (mammoth wildrye) and Ammophila arenaria (L.) Link (marram grass) are perennial, psammophilous species which dominate sand dunes due to their biological characteristics. Their communities have an important role in the formation of the natural vegetation cover of coastal sand strips along the Bulgarian Black Sea Coast. This study provides the first systematic analysis of tolerance of L. racemosus subsp. sabulosus and A. arenaria to sea water immersion along the Bulgarian Black Sea Coast. It aims to determine effects of flooding stress on whole plants and how long rhizomes can remain viable in sea water. Two experiments establish that decomposition of leaves of immersed plants starts from the 7th day. A growth of stems and root sprouts is observed on the same day. There are no visible decompositions of stems, roots and rhizomes till the end of the experiment (20th day). Rhizomes from the investigated species are able to regenerate after 30 days of submergence and bud viability appears to be enhanced slightly by sea water. L. racemosus subsp. sabulosus shows higher bud viability than A. arenaria. The possible negative consequences of flooding to L. racemosus and A. arenaria communities based on experimental results, hydrodynamical modelling, detailed topography, bathymetry surveys and detailed GIS mapping on Panorama Beach are discussed.Key words: Leymus racemosus subsp. sabulosus, Ammophila arenaria, immersion tolerance, viability, IDF modelsThis study is performed with the financial support of the THESEUS project "Innovative technologies for safer European coasts in a changing climate" (GA No 244104). 211Introduction. Leymus racemosus (Lam.) Tzvelev subsp. sabulosus (M. Bieb.) Tzvelev (mammoth wildrye) and Ammophila arenaria (L.) Link (marram grass) are erect, perennial, rhizomatous grass species [ 1 ]. They are major psammophilous species which dominate sand dunes due to their biological characteristics and their communities have an important role in the formation of the natural vegetation cover of coastal sand strips along the Bulgarian Black Sea Coast. These closely-related species form an extensive system of horizontal and vertical rhizomes that support sand stabilization. A good example of the high potential of the root system of these two species to accumulate sands and prevent from washout is the storm in March 2010 in Panorama Natural Beach situated north of the Golden Sands Resort near the town of Varna. A great amount of sediments are preserved within the beach boundaries (Fig. 1), unlike the neighbouring Golden Sands urbanized beach.Despite their high resistance, L. racemosus subsp. sabulosus and A. arenaria are vulnerable and sensitive to the impact of waves and storms. These factors in combination with anthropogenic impact may lead to various negative consequences. Plants could be affected by direct storm-wave damage, during which they are uprooted or buried by sediments. Furthermore, leaf, stem and root decomposition process...

Abstract. Storms are one of the most important phenomena producing coastal hazards and endangering human life and activities. In recent decades storm climate has become a subject of increased public awareness and knowledge of this issue can help the society to meet future challenges related to extreme storm manifestation. Therefore, the goal of this study is to assess trends in past and recent storminess in the western Black Sea. The analysis of storm climate is based on a continuous hindcast dataset covering a substantial historical time-span of 63 yr . It was used to create a storm population and to estimate properties describing storminess (proxies). This was done by introduction of criteria allowing separation of events with low probability of occurrence and at the same time keeping the information on their pattern, i.e. properties of storm phases. Eleven storminess proxies were analysed and the most indicative appeared to be storm duration; integral, mean and specific storm wave energy; and wind velocity and direction, which were obtained for each storm season.While experiencing significant variability on a quasidecadal scale, no significant upward or downward trends in storminess were detected. For almost all proxies, an increasing trend until the 1980s or the 1990s and a return to average or even calm conditions in the late 2000s are traceable. On this background, a steady although not significant increase of wind velocity was detected. Results also indicate an alteration of storm pattern, manifested as shortening of storm duration due to a shift of the prevailing direction of storm forcing winds to the north. Nevertheless, incident wave energy in the storms' most intense phase remains significant. The obtained results are discussed with regard to the influence of the North Atlantic Oscillation on the hydrometeorological pattern of the Black Sea region as a part of the EuropeanAtlantic area, in particular with respect to the cyclonic activity.