Weather- and climate-related natural hazards in Europe

Since 2003, Europe has experienced several extreme summer heat waves. Such heat waves are projected to occur as often as every 2 years in the second half of the 21st century, under a high emissions scenario (RCP8.5). The impacts will beparticularly strong in southern Europe.Heavy precipitation events have increased in northern and north-eastern Europe since the 1960s, whereas different indices show diverging trends for south-western and southern Europe. Heavy precipitation events are projected tobecome more frequent in most parts of Europe.The number of very severe flood events in Europe has varied since 1980, but the economic losses have increased. It isnot currently possible to quantify the contribution due to increased heavy precipitation in parts of Europe compared with better reporting and land use changes.Observations of windstorm location, frequency and intensity have showed considerable variability across Europe during the 20th century. Models project an eastward extension of the North Atlantic storm track towards central Europe, with an increase in the number of cyclones in central Europe and a decreased number in the Norwegian and Mediterranean Seas.For medicanes (also termed Mediterranean Sea hurricanes), a decreased frequency but increased intensity of medicanes is projected in the Mediterranean area.Landslides are a natural hazard that cause fatalities and significant economic losses in various parts of Europe. Projected increases in temperature and changes in precipitation patterns will affect rock slope stability conditions and favour increases in the frequency of shallow landslides, especially in European mountains.The severity and frequency of droughts appear to have increased in parts of Europe, in particular in southern and south-eastern Europe. Droughts are projected to increase in frequency, duration, and severity in most of Europe, with the strongest increase projected for southern Europe.Forest fire risk depends on many factors, including climatic conditions, vegetation, forest management practices and other socio-economic factors. The burnt area in the Mediterranean region increased from 1980 to 2000; it has decreased thereafter. Projected increases in heat waves together with an expansion of the fire-prone area will increase the duration of fire seasons across Europe, in particular in southern Europe.Observational data between 1970 and 2015 show that alpine avalanches cause on average 100 fatalities every winter in the Alps. Increased temperatures are expected to lead to decreases in alpine snow cover and duration, and in turnto decreased avalanche activity below about 1 500-2 000 m elevation in spring, but increased avalanche activity above 2 000 m elevation, especially in winter.Hail is responsible for significant damage to crops, vehicles, buildings and other infrastructure. Despite improvements in data availability, trends and projections of hail events are still subject to large uncertainties owing to a lack of directobservation and inadequate microphysical schemes in numerical weather prediction and climate models.Extreme high coastal water levels have increased at most locations along the European coastline. This increase appears to be predominantly due to increases in mean local sea level rather than to changes in storm activity. Projected changes in the frequency and intensity of storm surges are expected to cause significant ecological damage, economic loss and other societal problems along low-lying coastal areas in northern and western Europe, unless additional adaptation measures are implemented.