Italy - Climate
Italy, located in the middle of the Mediterranean basin, is comprised of a continental northern sector, a peninsular central-southern sector, two large islands (Sardegna and Sicilia) and various archipelagos and minor islands. Italy has a heterogeneous climate which leads to differences in the immediate risks posed by climate change throughout the country.
Because Italy is mountainous and stretches 1,200 kilometers from central Europe almost to Africa, the climate is by no means uniform. Sunshine and low humidity draw visitors to resorts in the Alps and coasts of the Italian Riviera and peninsula. In most of Italy hot summers are relieved by sea or lake breezes, but farmers in the Mezzogiorno must cope with dry, blisteringly hot summers. Climatically, Italy can be divided into continental Italy, which consists of the Alpine and northern plain regions, peninsular or southern Italy, and insular Italy, which includes the islands of Sar- dinia and Sicily. Winter rather than summer temperatures and rainfall differentiate the continental climate from the rest of Italy, and rainfall increases with altitude.
Continental Italy, exposed to polar air in winter and warm winds from the distant Atlantic Ocean in summer, has a wide temperature range between winter and summer. Winters have fogs and frosts. In the Alps temperatures vary with the degree to which slopes are shaded or open to the sun, and precipitation varies ac- cording to relief. Areas over 1,500 meters receive snow, and some peaks remain snow-covered all year. The eastern Alps tend to be wetter, but as a whole, the Alpine region has a maximum of rain in summer as well as heavy precipitation in cooler months. Within the continental region other variations include the warmer Venetian coast and the sub-Alpine lakes, such as Maggiore, Como, and Garda, which are especially favored climatically because they contain large quantities of water, which moderate air temperatures, and because their shores are sheltered from the wind. As a whole, the North Italian Plain is sheltered on three sides (except the east) by mountains. Cold or cooler in winter than peninsular Italy, it receives little precipitation in winter, although humidity is high, and below-freezing temperatures are frequent. Spring on the plain is warm and wet, summer is hot and humid with frequent storms, and autumn is marked by heavy rains.
The narrowness of Italy's peninsula and the small size of the islands allow maritime influences to penetrate the interior, warming the autumn and making seasonal changes gradual. The presence of the Alps in the continental region and the Apennines in the peninsular region also modifies the weather of the coasts; the Apennines, for example, protect the Tyrrhenian coast, which is also warmed by the depth of the sea. In winter the mountains define cold areas between the coasts as in the case of the Abruzzi peaks, which have a long snow season from November to May. The typical Mediterranean climate characterized by hot, dry summers and moderate winters with good annual rainfall prevails only in the southern peninsula and the islands. The Adriatic shores of the eastern peninsula, however, have a drier, harsher climate than that of the Ligurian and Tyrrhenian coasts.
Several parts of Italy have severe seasonal winds. Two violent winds are associated with a fall in temperature, clear skies, and low humidity. On the Ligurian coast the winter wind from the Alps, called the mistral, poses a real danger to ships, even in harbors. Around Trieste and the northern Adriatic coast, a bitterly cold wind from the Alps, called the bora, blows so fiercely that some buildings have handrails for pedestrians to grasp. A less severe, dry, northerly wind, called the Tramontana, affects the Tyrrhenian side of the peninsula. A southwesterly wind, the siroc. co, blows from the Sahara. On the Tyrrhenian side it is called the sciroccoso when it causes humid, stifling weather, but in Sicily and southern Italy it retains its parching Saharan character. On Sicily it is accompanied by sustained high temperatures harmful to crops and the health of infants and the sick.
It is possible that climate change effects on subsistence economies in Sub-Saharan Africa will also push increasing numbers of people not only to move across borders, but also to cross the sea to reach Europe and Italy specifically. Nevertheless, with the available data it would be impossible to attribute exact numbers of arrivals to climate change-driven intercontinental migration. Under high emissions climate change scenarios, predictions indicate that climate-driven migration will happen and will be very clearly identifiable in the Mediterranean area, with tens of millions of people at a time displaced by extreme weather events, and many millions more displaced by climate processes like desertification, salinization of agricultural land and sea level rise.
Under a high emissions scenario, the number of days with very heavy precipitation (20 mm or more) could increase by about 4 days on average from 1990 to 2100, increasing the risk of floods. Some models indicate increases outside the range of historical variability, implying even greater risk. If global emissions decrease rapidly, the risk is slightly reduced. Under a high emissions scenario, the longest dry spell is indicated to increase from an average of about 30 days to just under 45 days, with continuing large yearto-year variability. If global emissions decrease rapidly, there is little change in the length of dry spells.
Under a high emissions scenario, the number of days of warm spell is projected to increase from about 10 days in 1990 to about 250 days on average in 2100. If global emissions decrease rapidly, the days of warm spell are limited to about 75 on average. A ‘warm spell’ day is a day when maximum temperature, together with that of at least the 6 consecutive previous days, exceeds the 90th percentile threshold for that time of the year.
In the international context, Italy has the highest heatrelated effects on daily mortality considering both hot temperatures (from 90th to 99th percentile, 4 degrees on average) and overall summer temperatures (from minimum mortality temperature (MMT) to 99th percentile). However, there is heterogeneity among Italian cities both in the heat effect and in the MMT. Heat effects are greater in larger urban areas (Turin, Milan, Bologna, Florence, Rome, Naples) and a progressive increase in MMT levels can be observed from North to South of Italy and throughout summer, thus accounting for local climate and population physiological adaptation.
A decreasing trend in heat related mortality risk was observed in Italian cities after the introduction of the national heat prevention plan. In particular, the reduction was shown for extreme temperatures when warnings were issued and prevention measures were activated. The increase in frequency and intensity of heat waves together with population ageing will have a significant impact on health in the future. Summer 2015 was associated with a 13% increase in deaths attributable to heat among the population aged 65+.
Mycotoxins, produced by toxigenic moulds affecting crops, are one of the most investigated and paradigmatic example of the potential impact of climate change on food safety and security. The production of mycotoxins is greatly influenced by environmental factors, such as temperature, humidity and drought. Until a few years ago, aflatoxins, among the most harmful mycotoxins, were not a matter of concern in Europe. However, 2003 and 2012 will be remembered in Italy and southern Europe, respectively, because of the alarming contamination in maize. Models aimed at predicting aflatoxin contamination in maize and wheat crops in Europe over the next 100 years indicate Italy will be one of the most heavily affected countries.
Climate change impacts are already exacerbating existing infrastructural deficiencies, post-industrial pollution phenomena and the intrinsic hydro-geological and seismic vulnerability of the country. Rising temperatures, coastal erosion, flooding and drought may lead to water scarcity (6 out of 20 regions called on the government to declare a state of emergency due to water stress in 2017). Water stress could also lead to a reduction in agricultural production, higher risk of forest fires, increased desertification and could threaten economic progress. In addition, climate change impacts air quality, particularly in urban settings, and may lead to changes in the spatial distribution of flora and fauna which degrades biodiversity.
There is a concrete risk of the re-emergence of previously endemic agents (with the occurrence of wild poliovirus in neighboring countries, or a potential increase of TB incidence), or the arrival of exotic communicable diseases, such as dengue, chikungunya, Zika, Crimean-Congo fever, West Nile fever or blue tongue. Protection strategies have been strengthened, but the risk is increasing.
In a region celebrated for the prosecco and pinot grigio it ships around the world, Italy’s particularly sensitive white wine grapes have become a telltale of even gradual temperature increases — a climate slipping from ideal to nearly ideal. Vintners and farmers are noticing more disease, an accelerated ripening process, and, most viscerally, a surge in the number of grapes that are singed by the intensifying summer heat.
An unprecedented wave of storms in 2018 knocked trees down in Italy’s forests and artisans are racing to salvage the valuable wood before it rots. More than 2,500,000 red spruce trees were felled in violent storms. Red spruce is a wood prized by violin-makers – and they were concerned that supplies of it are running out, which makes destructive weather like this even more devastating.
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