Climate of the Alps
Encyclopedia
The climate of the Alps is the climate
, or average weather
conditions over a long time, of the exact middle Alpine
region of Europe
. As air rises from sea level
to the upper regions of the atmosphere
the temperature
decreases. The effect of mountain
topography on prevailing wind
s is to force warm air from the lower region into an upper zone where it expands in volume
at the cost of a proportionate loss of heat
, often accompanied by the precipitation
of moisture in the form of snow
, rain
or hail
.
The position of the Alps in the central European continent profoundly affects the climate of all the surrounding regions. The accumulation of vast masses of snow, which have gradually been converted into permanent glacier
s, maintains a gradation of very different climates within the narrow space that intervenes between the foot of the mountains and their upper ridges; it cools breezes that waft
to the plain
s on either side, but its most important function is to regulate the water supply
of the large region which is traversed by the streams of the Alps. Nearly all the moisture that is precipitated during fall, winter, and spring is stored in the form of snow and gradually diffused.
.
Roughly one quarter of the land lying between the summits of the Alps is available for cultivation. Of this low country, about one half may be vineyard
s and grain
fields, while the remainder produces forage
and grass
. Of the high country, about half is utterly barren, consisting of snow fields, glacier
s, bare rock, lakes and stream beds. The other half is divided between forest and pasture, and the product of this half largely supports the relatively large population. For a quarter of the year the flocks and herds are fed on the upper pastures, but the true limit of the wealth of a district is the number of animals that can be supported during the long winter, and while one part of the population is engaged in tending the beasts and in making cheese
and butter
, the remainder is busy cutting hay
and storing up winter food for the cattle.
The larger villages are mostly in the mountain region, but in many parts of the Alps the villages stand in the subalpine region at elevations varying from 1200 m to 1700–1800 m (4000–6000 ft). The most characteristic feature of this region is the prevalence of coniferous
trees that, where they have not been removed, form vast forests that cover a large part of the surface. These play a most important part in the natural economy of the country. They retain the soil by their roots, protect the valleys from destructive avalanches and mitigate the destructive effects of heavy rains. In valleys where they have been cut away, waters pour down the slopes unchecked; every tiny rivulet becomes a raging torrent that carries off the grassy slopes and devastates the floor of the valley, covering the soil with gravel and debris.
In the conifer
forests of the Alps the prevailing species are the Norway Spruce
and the Silver Fir
; on siliceous soil the European Larch
flourishes. The Scots Pine
is chiefly found at a lower level and rarely forms forests. The Swiss Pine
is found scattered at intervals throughout the Alps but is not common. The Mountain Pine
is common at higher altitudes, often forming a distinct zone of Krummholz
above the level of its congener
s on the higher mountains. In the Northern Alps the pine forests rarely surpass 1800 m (6000 ft) elevation, but on the south side they commonly attain 2100 m (6900 ft), while European Larch, Swiss Pine and Mountain Pine often extend above that elevation.
The Alps are eponymous of the Alpine climate
typical of the Alps
between the tree line up to the permanent snow line, roughly between 1800 m and 2500 m.
This alpine
region contains the full beauty and variety of characteristic vegetation of the Alps.
The region contains many shrub
s:
more snow
falls in each year than melts. A portion of this is carried away by the wind before it is consolidated, but a large portion accumulates in hollows and depressions of the surface and is gradually converted into glacier
ice
which descends by slowly flowing into the deeper valleys where it help swell perennial streams.
Mountain snow does not lie in beds of uniform thickness and some parts are more exposed to the sun and warm air than others. Beds of snow commonly alternate with exposed slopes covered with brilliant vegetation without an obvious boundary of perpetual snow. A seemingly clear boundary seems visible when a high mountain chain is viewed from a distance: Similar conditions are repeated at many different points, so that the level at which large snow beds show themselves can be seen as approximately horizontal. But this is true only as far as the conditions are similar. On the opposite sides of the same chain the exposure to the sun or to warm winds may cause a wide difference in the level of permanent snow, though the increased fall of snow on the side exposed to moist winds may more than compensate for the sun's rays.
Still, the "line of perpetual snow" is not fixed. The occurrence of favorable meteorological conditions during several successive seasons may and does increase the extent of the snowfields and lower the limit of seemingly permanent snow, while the opposite may cause the limit to rise higher on the flanks of the mountains. Hence all attempts to fix accurately the level of perpetual snow in the Alps are fallacious. At best, local accuracy might be established for a particular district. In some parts of the Alps the limit is about 2400 m (7900 ft) elevation, while in others it cannot be placed much below 2900 m (9500 ft). As very little snow remains on rocks angled more than 60°, this is soon removed by the wind, some steep masses of rock remain bare even near the summits of the highest peaks, but as almost every spot offering the least hold for vegetation is covered with snow, few flowering plants are seen above 3350 m (11,000 ft).
There is reason to think, however, that it is the lack of soil
rather than climatic conditions that checks the upward extension of the alpine flora. Increased direct effect of solar radiation compensates for the cold of the nights, and in the few spots where plants have been found flowering up to a height of 3650 m (12,000 ft), nothing has indicated that the processes of vegetation were arrested by the severe cold which they must sometimes endure. The climate of the glacial region has often been compared to that of the polar regions, but they are very different. Here, intense solar radiation by day, which raises the surface when dry to a temperature approaching 27°C (80°F), alternates with severe frost by night. There, the Sun, which never sets is only able to send feeble rays that maintain a low temperature, rarely rising more than a few degrees above the freezing point. Hence the upper region of the Alps sustains a far more varied and brilliant vegetation.
has a winter climate colder than that of the British Isles. The olive
and the characteristic shrub
s of the northern coasts of the Mediterranean do not thrive in the open air, but the valuable tree ripens its fruit in sheltered places at the foot of the mountains, and survives along the deeper valleys and the shores of the Italian lakes.
The evergreen oak
grows wild on the rocks around the alpine lake, Lake Garda
, and even lemon
s are cultivated on a large scale, with partial protection in winter. The olive has been known to survive severe cold when of short duration, but it cannot be cultivated with success where frosts are prolonged or where the mean winter temperature falls below 5.5°C (42°F). To produce fruit requires at least 24°C (75°F) during the day through four or five months of the summer and autumn.
, but to produce tolerable wine
it demands, at the season of ripening, a degree of heat not much less than that needed by the more delicate tree. These conditions are satisfied in the deeper valleys of the Alps
, even in the interior of the chain, and up to a considerable height on slopes exposed to the Sun. The protection afforded by winter snow enables the plant to resist severe and prolonged frosts that would be fatal in more exposed situations. Many wild plants characteristic of the warmer parts of middle Europe are seen to flourish along with the vine. A mean summer temperature of at least 20°C (68°F) is considered necessary to produce tolerable wine, but in ordinary seasons this is much exceeded in many of the great valleys of the Alps.
Climate
Climate encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count and other meteorological elemental measurements in a given region over long periods...
, or average weather
Weather
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate...
conditions over a long time, of the exact middle Alpine
Alps
The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....
region of Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. As air rises from sea level
Sea level
Mean sea level is a measure of the average height of the ocean's surface ; used as a standard in reckoning land elevation...
to the upper regions of the atmosphere
Earth's atmosphere
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night...
the temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
decreases. The effect of mountain
Mountain
Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...
topography on prevailing wind
Wind
Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...
s is to force warm air from the lower region into an upper zone where it expands in volume
Volume
Volume is the quantity of three-dimensional space enclosed by some closed boundary, for example, the space that a substance or shape occupies or contains....
at the cost of a proportionate loss of heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
, often accompanied by the precipitation
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...
of moisture in the form of snow
Snow
Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by...
, rain
Rain
Rain is liquid precipitation, as opposed to non-liquid kinds of precipitation such as snow, hail and sleet. Rain requires the presence of a thick layer of the atmosphere to have temperatures above the melting point of water near and above the Earth's surface...
or hail
Hail
Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...
.
The position of the Alps in the central European continent profoundly affects the climate of all the surrounding regions. The accumulation of vast masses of snow, which have gradually been converted into permanent glacier
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
s, maintains a gradation of very different climates within the narrow space that intervenes between the foot of the mountains and their upper ridges; it cools breezes that waft
Waft
Waft is a term meaning to carry along gently as through the air. The term is commonly used to describe scents that have diffused in to other parts of a room, or to describe smoke as being seen moving through the air...
to the plain
Plain
In geography, a plain is land with relatively low relief, that is flat or gently rolling. Prairies and steppes are types of plains, and the archetype for a plain is often thought of as a grassland, but plains in their natural state may also be covered in shrublands, woodland and forest, or...
s on either side, but its most important function is to regulate the water supply
Water supply
Water supply is the provision of water by public utilities, commercial organisations, community endeavours or by individuals, usually via a system of pumps and pipes...
of the large region which is traversed by the streams of the Alps. Nearly all the moisture that is precipitated during fall, winter, and spring is stored in the form of snow and gradually diffused.
Subalpine Alps
The Subalpine is the region which mainly determines the manner of life of the population of the AlpsAlps
The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....
.
Roughly one quarter of the land lying between the summits of the Alps is available for cultivation. Of this low country, about one half may be vineyard
Vineyard
A vineyard is a plantation of grape-bearing vines, grown mainly for winemaking, but also raisins, table grapes and non-alcoholic grape juice...
s and grain
Cereal
Cereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...
fields, while the remainder produces forage
Fodder
Fodder or animal feed is any agricultural foodstuff used specifically to feed domesticated livestock such as cattle, goats, sheep, horses, chickens and pigs. Most animal feed is from plants but some is of animal origin...
and grass
Poaceae
The Poaceae is a large and nearly ubiquitous family of flowering plants. Members of this family are commonly called grasses, although the term "grass" is also applied to plants that are not in the Poaceae lineage, including the rushes and sedges...
. Of the high country, about half is utterly barren, consisting of snow fields, glacier
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
s, bare rock, lakes and stream beds. The other half is divided between forest and pasture, and the product of this half largely supports the relatively large population. For a quarter of the year the flocks and herds are fed on the upper pastures, but the true limit of the wealth of a district is the number of animals that can be supported during the long winter, and while one part of the population is engaged in tending the beasts and in making cheese
Cheese
Cheese is a generic term for a diverse group of milk-based food products. Cheese is produced throughout the world in wide-ranging flavors, textures, and forms....
and butter
Butter
Butter is a dairy product made by churning fresh or fermented cream or milk. It is generally used as a spread and a condiment, as well as in cooking applications, such as baking, sauce making, and pan frying...
, the remainder is busy cutting hay
Hay
Hay is grass, legumes or other herbaceous plants that have been cut, dried, and stored for use as animal fodder, particularly for grazing livestock such as cattle, horses, goats, and sheep. Hay is also fed to pets such as rabbits and guinea pigs...
and storing up winter food for the cattle.
The larger villages are mostly in the mountain region, but in many parts of the Alps the villages stand in the subalpine region at elevations varying from 1200 m to 1700–1800 m (4000–6000 ft). The most characteristic feature of this region is the prevalence of coniferous
Pinophyta
The conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being...
trees that, where they have not been removed, form vast forests that cover a large part of the surface. These play a most important part in the natural economy of the country. They retain the soil by their roots, protect the valleys from destructive avalanches and mitigate the destructive effects of heavy rains. In valleys where they have been cut away, waters pour down the slopes unchecked; every tiny rivulet becomes a raging torrent that carries off the grassy slopes and devastates the floor of the valley, covering the soil with gravel and debris.
In the conifer
Pinophyta
The conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being...
forests of the Alps the prevailing species are the Norway Spruce
Norway Spruce
Norway Spruce is a species of spruce native to Europe. It is also commonly referred to as the European Spruce.- Description :...
and the Silver Fir
Silver Fir
Abies alba, commonly known as the European silver fir, is a fir native to the mountains of Europe, from the Pyrenees north to Normandy, east to the Alps and the Carpathians, and south to southern Italy and northern Serbia.-Description:...
; on siliceous soil the European Larch
European Larch
Larix decidua, common name European larch, is a species of larch native to the mountains of central Europe, in the Alps and Carpathians, with disjunct lowland populations in northern Poland and southern Lithuania.-Description:...
flourishes. The Scots Pine
Scots Pine
Pinus sylvestris, commonly known as the Scots Pine, is a species of pine native to Europe and Asia, ranging from Scotland, Ireland and Portugal in the west, east to eastern Siberia, south to the Caucasus Mountains, and as far north as well inside the Arctic Circle in Scandinavia...
is chiefly found at a lower level and rarely forms forests. The Swiss Pine
Swiss Pine
The Swiss Pine or Arolla Pine, Pinus cembra, is a species of pine tree that occurs in the Alps and Carpathian Mountains of central Europe, in Poland , Switzerland, France, Italy, Austria, Germany, Slovenia, Slovakia, Ukraine and Romania. It typically grows at to altitude. It often reaches the...
is found scattered at intervals throughout the Alps but is not common. The Mountain Pine
Mountain Pine
Pinus mugo, the Mountain Pine or Mugo Pine, is a high-altitude European pine, found in the Pyrenees, Alps, Erzgebirge, Carpathians, northern Apennines and Balkan Peninsula mountains from 1,000 m to 2,200 m, occasionally as low as 200 m in the north of the range in Germany and Poland, and as high...
is common at higher altitudes, often forming a distinct zone of Krummholz
Krummholz
Krummholz or Krumholtz formation — also called Knieholz — is a particular feature of subarctic and subalpine tree line landscapes. Continual exposure to fierce, freezing winds causes vegetation to become stunted and deformed...
above the level of its congener
Congener
Congener has several different meanings depending on the field in which it is used. Colloquially, it is used to mean a person or thing like another, in character or action.-Biology:In biology, congeners are organisms within the same genus...
s on the higher mountains. In the Northern Alps the pine forests rarely surpass 1800 m (6000 ft) elevation, but on the south side they commonly attain 2100 m (6900 ft), while European Larch, Swiss Pine and Mountain Pine often extend above that elevation.
Alpine Region
Alpine climate
Alpine climate is the average weather for a region above the tree line. This climate is also referred to as mountain climate or highland climate....
typical of the Alps
Alps
The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....
between the tree line up to the permanent snow line, roughly between 1800 m and 2500 m.
This alpine
Alpine climate
Alpine climate is the average weather for a region above the tree line. This climate is also referred to as mountain climate or highland climate....
region contains the full beauty and variety of characteristic vegetation of the Alps.
The region contains many shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
s:
- Three speciesSpeciesIn biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of rhododendronRhododendronRhododendron is a genus of over 1 000 species of woody plants in the heath family, most with showy flowers...
have masses of redRedRed is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of roughly 630–740 nm. Longer wavelengths than this are called infrared , and cannot be seen by the naked eye...
or pinkPinkPink is a mixture of red and white. Commonly used for Valentine's Day and Easter, pink is sometimes referred to as "the color of love." The use of the word for the color known today as pink was first recorded in the late 17th century....
flowerFlowerA flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s; - The common junipers grow at elevations above the rhododendrons.
- Three species of bilberryBilberryBilberry is any of several species of low-growing shrubs in the genus Vaccinium , bearing edible berries. The species most often referred to is Vaccinium myrtillus L., but there are several other closely related species....
are associated with the junipers. - Several dwarf willowWillowWillows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...
s grow near the snow line.
Glacial Region
On the higher parts of lofty mountains in the AlpsAlps
The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....
more snow
Snow
Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by...
falls in each year than melts. A portion of this is carried away by the wind before it is consolidated, but a large portion accumulates in hollows and depressions of the surface and is gradually converted into glacier
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
ice
Ice
Ice is water frozen into the solid state. Usually ice is the phase known as ice Ih, which is the most abundant of the varying solid phases on the Earth's surface. It can appear transparent or opaque bluish-white color, depending on the presence of impurities or air inclusions...
which descends by slowly flowing into the deeper valleys where it help swell perennial streams.
Mountain snow does not lie in beds of uniform thickness and some parts are more exposed to the sun and warm air than others. Beds of snow commonly alternate with exposed slopes covered with brilliant vegetation without an obvious boundary of perpetual snow. A seemingly clear boundary seems visible when a high mountain chain is viewed from a distance: Similar conditions are repeated at many different points, so that the level at which large snow beds show themselves can be seen as approximately horizontal. But this is true only as far as the conditions are similar. On the opposite sides of the same chain the exposure to the sun or to warm winds may cause a wide difference in the level of permanent snow, though the increased fall of snow on the side exposed to moist winds may more than compensate for the sun's rays.
There is reason to think, however, that it is the lack of soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
rather than climatic conditions that checks the upward extension of the alpine flora. Increased direct effect of solar radiation compensates for the cold of the nights, and in the few spots where plants have been found flowering up to a height of 3650 m (12,000 ft), nothing has indicated that the processes of vegetation were arrested by the severe cold which they must sometimes endure. The climate of the glacial region has often been compared to that of the polar regions, but they are very different. Here, intense solar radiation by day, which raises the surface when dry to a temperature approaching 27°C (80°F), alternates with severe frost by night. There, the Sun, which never sets is only able to send feeble rays that maintain a low temperature, rarely rising more than a few degrees above the freezing point. Hence the upper region of the Alps sustains a far more varied and brilliant vegetation.
Olive Region
The great plain of upper ItalyItaly
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
has a winter climate colder than that of the British Isles. The olive
Olive
The olive , Olea europaea), is a species of a small tree in the family Oleaceae, native to the coastal areas of the eastern Mediterranean Basin as well as northern Iran at the south end of the Caspian Sea.Its fruit, also called the olive, is of major agricultural importance in the...
and the characteristic shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
s of the northern coasts of the Mediterranean do not thrive in the open air, but the valuable tree ripens its fruit in sheltered places at the foot of the mountains, and survives along the deeper valleys and the shores of the Italian lakes.
The evergreen oak
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
grows wild on the rocks around the alpine lake, Lake Garda
Lake Garda
Lake Garda is the largest lake in Italy. It is located in Northern Italy, about half-way between Brescia and Verona, and between Venice and Milan. Glaciers formed this alpine region at the end of the last ice age...
, and even lemon
Lemon
The lemon is both a small evergreen tree native to Asia, and the tree's ellipsoidal yellow fruit. The fruit is used for culinary and non-culinary purposes throughout the world – primarily for its juice, though the pulp and rind are also used, mainly in cooking and baking...
s are cultivated on a large scale, with partial protection in winter. The olive has been known to survive severe cold when of short duration, but it cannot be cultivated with success where frosts are prolonged or where the mean winter temperature falls below 5.5°C (42°F). To produce fruit requires at least 24°C (75°F) during the day through four or five months of the summer and autumn.
Vine Region
The grape vine is far more tolerant of cold than the oliveOlive
The olive , Olea europaea), is a species of a small tree in the family Oleaceae, native to the coastal areas of the eastern Mediterranean Basin as well as northern Iran at the south end of the Caspian Sea.Its fruit, also called the olive, is of major agricultural importance in the...
, but to produce tolerable wine
Wine
Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...
it demands, at the season of ripening, a degree of heat not much less than that needed by the more delicate tree. These conditions are satisfied in the deeper valleys of the Alps
Valleys of the Alps
-Rhine basin :High Rhine*Aare**Limmat***Linth ****Lake Walen*****Seez****Klöntal****Sernftal**Reuss River***Lake Lucerne****Sarner Aa ****Muotathal***Schächen, Klausen Pass connects to Glarus...
, even in the interior of the chain, and up to a considerable height on slopes exposed to the Sun. The protection afforded by winter snow enables the plant to resist severe and prolonged frosts that would be fatal in more exposed situations. Many wild plants characteristic of the warmer parts of middle Europe are seen to flourish along with the vine. A mean summer temperature of at least 20°C (68°F) is considered necessary to produce tolerable wine, but in ordinary seasons this is much exceeded in many of the great valleys of the Alps.