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The present study investigates different combinations and methods for estimating the extreme Total Water Level (TWL) and its implications for predicting flood extension caused by coastal storms. This study analyses various TWL components and approaches and assesses how different methodologies alter flood predictions, with implications for warning systems and emergency responses. Using different combinations of individual TWL components, flood extension simulations were conducted using a hydrodynamic model in the Volano Beach area (Emilia-Romagna, Italy). A real coastal storm event was used as a reference for comparison. The findings indicate that the selection of individual TWL components and calculation methods significantly impacts flood extension predictions. The approaches, which involve calculating extreme values from a combined time series or the water level time series plus the extreme value of wave setup, yield the most realistic results, excluding the runup component. In comparison, the other combinations overestimate the flood. Incorporating hydromorphological models like XBeach could enhance the accuracy of runup estimations and improve the overall method reliability. Despite limitations such as runup estimation and the use of generic regional parameters, this study underscores the importance of the TWL combination selection in accurately predicting flood extents, emphasising the need for context-specific adaptations in environmental contexts. [ABSTRACT FROM AUTHOR]

This work presents the approach used to estimate coastal flood impact, developed within the EU H2020 European Coastal Flood Awareness System (ECFAS) Project, for assessing flood direct impacts on population, buildings, and roads along the European coasts. The methodology integrates object-based and probabilistic evaluations to provide uncertainty estimates for damage assessment. The approach underwent a user-driven co-evaluation process, it was applied to 16 test cases across Europe and validated against reported impact data in three major reference cases: Xynthia at La Faute-sur-Mer (France) in 2010, Xaver at Norfolk (UK) in 2013, and Emma at Cadiz (Spain) in 2018. A comparison with grid-based damage evaluation methods was also conducted. The findings demonstrate that the ECFAS Impact approach offers valuable estimates for affected populations, reliable damage assessments for buildings and roads, and improved accuracy compared to traditional grid-based approaches. The methodology also provides information for prevention and preparedness activities, facilitates further evaluations of risk scenarios and cost-benefit analysis of disaster risk reduction strategies. The approach is a tool suitable for large-scale coastal flood impact assessments, offering improved accuracy and operational capability for coastal flood forecasts. It represents a potential advancement of the existing EU-scale impact method used by the European Flood Awareness System (EFAS) for riverine flood warnings. The integration of object-based and probabilistic evaluations, along with uncertainty estimation, enhances the understanding and management of flood impacts along the European coasts. [ABSTRACT FROM AUTHOR]

Coastal flooding is recognized as one of the most devastating natural disasters, resulting in significant economic losses. Therefore, hazard assessment is crucial to support preparedness and response to such disasters. Toward this, flood map databases and catalogues are essential for the analysis of flood scenarios, and furthermore they can be integrated into disaster risk reduction studies. In this study and in the context of the European Coastal Flood Awareness System (ECFAS) project (GA 101004211), which aimed to propose the European Copernicus Coastal Flood Awareness System, a catalogue of flood maps was produced. The flood maps were generated from flood models developed with LISFLOOD-FP for defined coastal sectors along the entire European coastline. For each coastal sector, 15 synthetic scenarios were defined focusing on high-frequency events specific to the local area. These scenarios were constructed based on three distinct storm durations and five different total-water-level (TWL) peaks incorporating tide, mean sea level, surge and wave setup components. The flood model method was extensively validated against 12 test cases for which observed data were collated using satellite-derived flood maps and in situ flood markers. Half of the test cases represented well the flooding with hit scores higher than 80 %. The synthetic-scenario approach was assessed by comparing flood maps from real events and their closest identified scenarios, producing a good agreement and global skill scores higher than 70 %. Using the catalogue, flood scenarios across Europe were assessed, and the biggest flooding occurred in well-known low-lying areas. In addition, different sensitivities to the increase in the duration and TWL peak were noted. The storm duration impacts a few limited flood-prone areas such as the Dutch coast, for which the flooded area increases more than twice between 12 and 36 h storm scenarios. The influence of the TWL peak is more global, especially along the Mediterranean coast, for which the relative difference between a 2- and 20-year return period storm is around 80 %. Finally, at a European scale, the expansion of flood areas in relation to increases in TWL peaks demonstrated both positive and negative correlations with the presence of urban and wetland areas, respectively. This observation supports the concept of storm flood mitigation by wetlands. [ABSTRACT FROM AUTHOR]

Coastal flooding is recognized as one of the most devastating natural disasters, resulting in significant economic losses. Therefore, hazard assessment is crucial to support preparedness and response to such disasters. Toward this, flood map databases and catalogues are essential for the analysis of flood scenarios, and furthermore can be integrated into disaster risk reduction studies. In this study and in the context of the ECFAS project (GA 101004211), which aimed to propose a European Copernicus Coastal Flood Awareness System, a catalogue of flood maps was produced. The flood maps were generated from flood models developed with LISFLOOD-FP for defined coastal sectors along the entire European coastline. For each coastal sector, fifteen synthetic scenarios were defined focusing on high-frequency events specific to the local area. These scenarios were constructed based on three distinct storm durations and five different Total Water Level (TWL) peaks incorporating tide, mean sea level, surge and wave set-up components. The flood model method was extensively validated against twelve test cases for which observed data were collated using satellite-derived flood maps and in situ flood markers. Half of the test-cases well represented the flooding with hit scores higher than 80 %. The synthetic scenario approach was assessed by comparing flood maps from real events and their closest identified scenarios, producing a good agreement and global skill scores higher than 70 %. Using the catalogue, flood scenarios across Europe were assessed, and the biggest flooding occurred in well-known low-lying areas. In addition, different sensitivities to the increase of the duration and TWL peak were noted. The storm duration impacts a few limited flood prone areas such as the Dutch coast for which the flooded area increases more than twice between a 12 h and 36 h storm scenarios. The influence of the TWL peak is more global, especially along the Mediterranean coast for which the relative difference between a 2- and 20-year return period storm is around 80 %. Finally, at a European scale, the expansion of flood areas in relation to increases in TWL (Total Water Level) peaks demonstrated both positive and negative correlations with the presence of urban and wetland areas, respectively. This observation supports the concept of storm flood mitigation by wetlands. [ABSTRACT FROM AUTHOR]

Household air pollution (HAP) from biomass fuel smoke is a major health risk, especially in developing countries. The ventilation of buildings and the type of fume discharge could also affect HAP. The present study aims to investigate the impact of stove type and kitchen characteristics on levels of pollutants. In particular, we investigated the potential geometric ventilation of buildings using geometric ventilation index (GVI), the presence of chimneys, the type of fuel and the environmental carbon monoxide level (a marker of indoor pollution) in the households of four Sherpa villages located in a mountain region of Nepal at altitudes between 2500 and 3900 m. We analysed 114 buildings (76 private residences and 38 lodges that accommodate tourists). Lodges had a more effective discharge system and a higher GVI, which had an inverse, significant correlation with indoor CO levels (r = 0.52). The level of indoor CO was more than 50% higher in private residences than in lodges. In the univariate analysis, only the absence of a chimney was associated with higher indoor CO (OR 3.4 (CL95%, 1.2–10.0), p = 0.02). We conclude that the adoption of chimneys and sealed stoves with exhaust pipes should be the first measure taken to reduce pollutants inside the households of high mountain regions until a switch to clean fuels can be achieved. [ABSTRACT FROM AUTHOR]

Integrated risk assessment approaches to support coastal managers' decisions when designing plans are increasingly becoming an urgent need. To enable efficient coastal management, possible present and future scenarios must be included, disaster risk reduction (DRR) measures integrated, and multiple hazards dealt with. In this work, the Bayesian Network approach to coastal risk assessment was applied and tested at two Mediterranean sandy coasts (Tordera Delta in Spain and Lido degli Estensi-Spina in Italy). Process-oriented models are used to predict hazards at the receptor scale based on a large number of storm characteristics. Hazards are converted into impacts through vulnerability relations. A Bayesian Network integrates all results to link forcing characteristics with expected impacts through conditional probabilities. The tool has been proven successful in reproducing current coastal responses at both sites. It has also shown great utility for scenario comparisons, and is able to output significant impact change trends, despite the inherent uncertainties of the approach. This work highlights the advantages of using such a tool for present and future coastal risk assessment and planning. [ABSTRACT FROM AUTHOR]

Developing and implementing a quick response post-storm survey protocol has the potential to improve impact assessments of coastal storms. Pre- and post-event surveys are essential to properly quantify the storm impacts on the coast. In this study, a combination of traditional RTK GPS and Unmanned Aerial Vehicle drone platform was utilized as part of a coordinated storm response workflow. The comprehensive approach employed in this pilot case study was conducted on the Emilia-Romagna coast (Italy), in the immediate aftermath of an extreme storm event that impacted the shoreline on the 5th-6th February 2015 called the Saint Agatha Storm. The activities were supported by timing information on the approaching storm provided by the regional early warning system. We collected aerial photos from a commercial off-the-shelf drone immediately after the Saint Agatha Storm and generated both orthomosaic and digital elevation models utilizing structure-from-motion photogrammetry techniques. The drone-based survey approach allowed us to quickly survey an area of 0.25 km2 within a 10-minute flight resulting in a ground sampling distance of 2.5 cm/pixel. Flooding and erosion impacts are analyzed and presented for the target study area. Limitations and possible applications for coastal management of the quick response post-storm surveying protocol are highlighted. [ABSTRACT FROM AUTHOR]

Purpose: Endothelial function and carotid intima-media thickness (IMT), are established markers of vascular aging. Aim of the study was to investigate the presence of early markers of atherosclerosis in rural Sherpa population of Kumbu Valley (Nepal), in comparison with lowlanders Caucasian subjects.Methods: 99 Sherpa subjects, living at 2500-3800 m s.l. (34±12 years, BMI 24±3 kg/mq, mean BP 88±9 mmHg), free of cardiovascular disease and risk factors, were recruited, and compared to 60 Caucasian sea-level healthy volunteers (36±12 years, BMI 23±2 kg/mq, mean BP 86±8 mmHg). Endothelial function in the brachial artery (flow-mediated dilation, FMD, and response to glyceryl trinitrate, GTN), and carotid IMT were measured by automated edge-detection system. Left and right ventricular (LV and RV) systolic and diastolic function and pulmonary systolic pressure (PASP), and pulmonary vascular resistance (PVR) were evaluated by echocardiogram. In 11 subjects with reduced FMD, the protocol was repeated, after 100% O2 administration for 1 hour, titrated to maintain O2 saturation around 100%.Results: High-altitude group presented higher heart rate and lower pulse pressure than sea-level group. FMD was also reduced (5.2±3.1 vs 6.8±3.0%, p=0.01), despite similar brachial artery diameter (3.7±0.6 vs 3.6±0.7 mm, p=0.64), and response to GTN (8.3±3.1 vs 7.6±2.2%, p=0.13). Conversely, IMT was lower in high altitude group than in the sea-level group (0.51 vs 0.61 mm, p<0.001). Sherpa people showed normal LV and RV systolic and diastolic function, PASP(28±6 mmHg) and PVR (0.16±0.4). In the overall population FMD (5.2±3.1%) was not correlated to O2 saturation (r=-0.03, p=0.74) and was similar in people with O2 saturation >90% and in those <90% (5.3 vs 5.0%, p=0.74). In the subgroup receiving O2 administration, FMD (from 3.1±2.5 to 3.8±2.6, p=0.46), response to GTN (from 8.9±2.7 to 8.7±1.9%), and echocardiographic parameters remained unchanged.Conclusions: Endothelial function is reduced in healthy Sherpa high-altitude dwellers, in the presence of normal RV and LV function and pulmonary pressures, independently of cardiovascular risk factors and hypoxia. This finding is accompanied with a lower IMT and might represent a physiological adaptation to high altitude. [ABSTRACT FROM AUTHOR]

Coastal flooding estimation at large scale, e.g. pan-European is usually performed using static method while dynamic method, in which numerical flood models are used to solve hydrodynamic equations, have proven to perform better. However, a numerical flood model can rapidly become computationally demanding. Thus, to respect the balance between efficiency and quality, models need to be properly configured. Usually, the model configuration is supported by calibration and validation. In the cases where it is not possible to appropriately implement calibration and validation through comparison against observed and measured data, sensitivity analyses can be applied in order to identify the key parameters that could influence the model capability to properly represent the modelled process. The present work aimed to identify influential model parameters across Europe and their relative importance in flood model configuration. Seventeen test cases were selected for which a LISFLOOD-FP model was developed, covering several sites across Europe and considering different storm events. A panoply of local morphologies and boundary conditions derived from the sites and storm event characteristics were used. For each test case, 72 simulations with different configurations were performed by varying the grid resolution, the numerical solver, the bottom friction and the wave set-up formulation used to estimate the total water level as a boundary condition. Two sensitivity analyses were performed on the modelled maximum flooded areas and water volumes using One-Driver-At-a-Time and variance-based methods. By using a k-means clustering method, the results of these sensitivity analyses allowed us to identify patterns through the test cases related to the geographical region, providing important information for the configuration of flood models across Europe. Both sensitivity analysis methods led to similar results highlighting dominant relative influences from the floodplain solver on the Atlantic coasts and from the boundary conditions on the Mediterranean ones. In addition the grid resolution was found to have great effect on the North and Baltic seas, while globally the friction was shown to impact the model's results less. The test cases were clustered using a k-means method using as input both the sensitivity analysis results and morphological factors. Depending upon the inputs, two different sets of clusters were generated revealing a complex relationship between the influence of the model's parameters and the selected morphological indicators. • 17 test cases of coastal flooding in Europe were simulated using LISFLOOD-FP model. • One-Driver-At-a-Time and variance based sensitivity analyses identified key parameter. • Significant influence of the floodplain solver, wave set-up and grid resolution. • Result models were relatively not sensitive to the friction configuration. [ABSTRACT FROM AUTHOR]