Trends of change in wind direction and velocity during the second part of the last century are examined at 17 coastal Italian stations along a north-south transect over 1000 km long in the central Mediterranean area. Linear regressions and confidence ranges are provided for the frequency and for annual maximum and mean velocities. It appears that wind activity has been mostly decreasing from 1951 to about the mid-1970s, and increasing after that time. Deviation from the general trend at certain stations is interpreted as possibly depending on local or regional phenomena. The general trends obtained show a positive correlation with temperature changes, whereas they do not correlate with North Atlantic oscillation index variability.

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Abstract. This is the first modeling reconstruction of the whole aspects (both meteorological and oceanographic) of the storm which hit Italy on 4 November 1966, producing 118 victims and widespread damages in Tuscany, at the northern Adriatic coast and in the north-eastern Italian Alps. The storm was produced by a cyclone which formed in the western Mediterranean and moved eastward towards Italy, reaching the Thyrrenian Sea, and then northward. The most peculiar characteristic of the storm has been the strong zonal pressure gradient and the consequent intensity and long fetch of the south-easterly sirocco wind, which advected a large amount of warm moist air, and determined exceptional orographic precipitation over Tuscany and the north-eastern Alps. The funneling of the wind between the mountain chains surrounding the Adriatic basin further increased the wind speed and determined the highest ever recorded storm surge along the Venetian coast.This study shows that present models would be able to produce a reasonably accurate simulation of the meteorological event (surface pressure, wind and precipitation fields, and storm surge level). The exceptional intensity of the event is not suggested by single parameters such as the sea level pressure minimum, the wind speed or the total accumulated precipitation. In fact, the precipitation was extreme only in some locations and the pressure minimum was not particularly deep. Moreover, the prediction of the damages produced by the river run-off and landslides would have required other informations concerning soil condition, snow coverage, and storage of water reservoirs before the event. This indicates that an integrated approach is required for assessing the probability of such damages both on a weather forecast and on a climate change perspective.

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Recent evolution of surge-related events and assessment of coastal flooding risk on the eastern coasts of the English Channel Abstract This paper is based on statistical analysis of hourly tide measurements for some 285 equivalent full years from the stations of Weymouth, Bournemouth, Portsmouth, Newhaven, Dover and Sheerness in the UK, and of Cherbourg, Le Havre, Dieppe, Boulogne, Calais and Dunkirk in France. For each tidal value, surge heights have been determined and correlated with hourly or three-hourly wind and air pressure data from nearby meteorological stations. Major surges in the area are generally produced by storms associated with wind from north-west or south-west that tend to push oceanic water into the Channel. Recent medium-term climate evolution does not seem to increase the flooding risk at French stations, where surge-related winds tend to decrease in frequency and speed (Cherbourg, Dieppe and Boulogne) or show little change (Le Havre). However, the long-term risk of flooding will increase through the loss in land elevation due to a continuation of the local relative sea-level rise, especially if this effect will be enhanced by an acceleration in the global sea-level rise predicted by climatic models. The northern side of the Channel (Weymouth, Bournemouth and Portsmouth) is mainly exposed to southerly winds that show variable trends. It is also apparently affected by strong subsidence trends during the last two decades. If lasting, such trends can only increase long-term flooding risk. The flooding risk has not increased near the eastern end of the Channel. The duration of significant cyclonic events tends to decrease near Cherbourg but tends to increase near Weymouth, with no conclusive trends in other stations (Portsmouth, Calais and Dunkirk), where extreme surges may occur also in relatively high-air-pressure situations. In conclusion, medium-term coastal flooding risk seems to increase especially at Weymouth, Bournemouth and Portsmouth, and also, but less so, at Le Havre and Sheerness. In addition, few extreme surges occurred during the last decades at the time of spring high tide, which would seem to be a fortunate coincidence or, in some cases, an effect of tide-surge interaction. The risk of occurrence of less favourable random events in the near future is therefore of concern, and flood potential would greatly increase if the global sea-level rise expected in the near future is also considered.

Low-lying coastal areas are often prone to storm surge flooding that can render severe damages to properties, destruction of habitats, threat to human safety and the environment. The impacts of coastal flooding are also expected to increase in the future as a consequence of global climate change and sea-level rise. This paper presents a comprehensive assessment of the potential risks raised by storm surge and sea-level rise on multiple coastal targets (i.e., population, buildings, infrastructures, agriculture, natural and semi-natural environments and cultural heritage) in the Northern Adriatic coast in Italy. Through the assessment of hazard, exposure, vulnerability and risk, a Regional Risk Assessment (RRA) methodology allowed identifying and prioritizing hot-spot risk areas and targets requiring particular attention for the definition of adaptation strategies. Hazard scenarios were based on the analysis of tide gauge data (elaborated with the Joint Probability Method) and of different sea-level rise projections for the year 2100. Geographical-information analysis was then used to characterize vulnerability patterns of exposed natural and human systems and to make a spatial ranking of risks. Maps produced for the worst scenario showed that beaches are the target at higher risk (with more than 90% of the surface in the higher relative risk class) due to the low elevation and high proximity to the coastline. Also cultural heritage (i.e., villas, historical buildings and roads) and wetlands are highly threatened by storm surge flooding. The relative risks will be lower (i.e., between 25% and 40% of their surface/length in the higher relative risk class) for most of the other receptors (i.e., local roads, railways, natural and semi-natural environments and agricultural areas), including population and buildings that are mostly classified in lower risk classes. The overall results of the assessment, including maps and risk metrics, can be useful to rise the attention of coastal managers about the need to adapt to climate change, developing climate-proof policies and programs for the sustainable management of coastal zones