May it snow in July

Mountain climate and altitude levels in the Alps

It can snow on the Zugspitze even in June and July. And not only there: On some alpine glaciers, skiing is possible in summer, even if there is bathing weather down in the valley. But why is it that there is a completely different climate just a few kilometers apart?

As the altitude increases, the temperature drops by around 6 degrees Celsius per 1000 meters of altitude. It may be that on the Zugspitze at 2,962 meters above sea level, only -1 ° C is measured. At the same time in Munich, at 519 meters above sea level, the thermometer rises to 14 ° C. In mountain regions, because of the high altitude, it is much colder than in lower regions of the same latitude. And something else changes with altitude, namely the rainfall. Because cold air can store less moisture than warm air, it rains or snows more above than below. Even in the tropics, there is therefore snow on high mountains such as the Andes or Kilimanjaro.

Depending on the falling temperatures and increasing precipitation, the type of vegetation also changes. In the mountains, different vegetation zones, called altitude levels, are formed in a small space. In some cases, the boundaries of these altitude levels can be clearly seen, for example the tree or snow line.

In the Alps and other high mountains of the moderate latitudes, the altitude levels begin with the so-called hill country level, in which agriculture is still practiced. The mountain step with mixed and coniferous forests follows in the direction of the summit. Above the tree line, only various dwarf shrubs and meadows thrive, which in summer are often used as pastures for alpine farming. Above the snow line there is no vegetation at all because cold, snow and ice prevent plant growth.

Mountains also have such altitudes in other climatic zones. However, other plant communities thrive there and the altitude levels are shifted: the snow line in the tropics is much higher than in the Alps, for example.

High and low mountain ranges

The Feldberg in the Black Forest is particularly popular with winter sports enthusiasts. Because of its height of 1493 meters, it is easy to ski here. But the Black Forest, although it has high mountains, is one of the German low mountain ranges. The Alps, on the other hand, are high mountains. But what is the difference between low and high mountains?

The simplest answer is obvious: they differ in their height. High mountains start at 1500 - some say 2000 - meters above sea level. So there are mountains whose peaks protrude far above the tree line. Another typical feature of high mountains is that they are formed by glaciers and have steep mountain walls.

Low mountain ranges, on the other hand, have neither glaciers nor steep slopes. Your landscape is rather hilly and rounded. This is because it was created much further back than that of the Alps. Originally, they too were piled high in the mountains - more than 300 million years ago. But unlike in the Alps, there has been no uplift in the low mountain ranges for a long time. They are only removed and their shapes are rounded. Some of them are already so badly weathered and worn that only the trunk remains of the former high mountains: the trunk mountains. These include, for example, the Ore Mountains and the Fichtel Mountains.

During their long history, the low mountain ranges have been constantly redesigned. Even the unfolding of the Alps did not leave them without a trace. The forces of the clashing plates put the old hulls of the low mountain range under a lot of pressure. Because of its old age, however, the rock had become so firm and rigid that it could not be folded any further. Instead, like a gigantic sheet of ice, it shattered into huge clods. Some sank, others began to rise. Sinking clods became deep trenches, rising clods developed into high plateaus. The landscape that emerged from it are broken clod mountains like the Harz. Its highest mountain, the Brocken, is 1141 meters high. That is not enough for the high mountains, so that the Harz clearly belongs to the low mountain ranges.

Temperate zone

Freezing cold or scorching heat is rare here. Extreme temperatures are rarely measured in the temperate zone. Precipitation falls all year round: in summer as rain or hail, in the cold season sometimes as snow. Germany is also located in these temperate latitudes, which lie between the subtropics and the polar regions.

In the northern hemisphere, western and central Europe are part of the temperate latitudes, as well as the central part of North America and Central Asia. This climatic zone has a much smaller area in the southern hemisphere: New Zealand, Southeast Australia, South Africa and South America belong to it. More than a third of the world's population lives in the moderate latitudes, especially the highly developed industrial nations such as the USA, Japan, China and many European countries.

Spring, summer, autumn and winter - distinct seasons are a special characteristic of the temperate zone. Because the temperatures change with the rhythm of the seasons, the vegetation has adapted. In order to survive the frost in winter, the deciduous trees shed their leaves in autumn and form new ones in spring. Conifers are particularly well protected against extreme cold by the wax layer on their needles. Deciduous and mixed forests are the typical vegetation in the temperate latitudes.

The closer we get to the poles, the colder it gets. In this cold-temperate zone with its long winters, mainly conifers grow because they are particularly well adapted to icy temperatures. In the northern hemisphere, therefore, there is a wide belt of coniferous forests in large parts of Canada and Russia, also known as the taiga.

Typical of the temperate zone is: the further inland you get, the drier it gets. While it rains a lot all year round in the French town of Brest on the Atlantic Ocean, in Siberia it is much drier in the interior of the continent. There, the temperature differences between summer and winter are much higher. Such a dry climate with strong temperature fluctuations is called a continental climate. Because of the great drought, hardly any forest grows here. In contrast, steppes are increasingly found - depending on the region also called prairies (North America) or pampas (South America). In some places it is even so dry that semi-deserts and deserts like the Gobi in Central Asia have formed.

What are climate zones?

“In the morning it is changing to very cloudy with showers. In the afternoon the sun shows up at temperatures between 16 and 22 degrees ”, this is perhaps the weather report for southern Germany. The forecast is interesting for us because the weather is constantly changing. The situation is different with the climate, because that remains. Climate is the average weather in a region over a longer period of time. For example, the climate at the equator is hot and humid all year round. At the North Pole, on the other hand, the temperatures are icy and there is little precipitation. Between the equator and the poles there are again areas where, like us, things can be very changeable. But why is it that the earth's climate is so different?

The sun's radiation is not equally strong all over the world. How intensely it warms the earth depends on the angle of the sun's rays and thus on the latitude. Because the sun near the equator is almost vertical all year round, the earth is very heated here. In the direction of the poles, the rays of the sun strike at an ever flatter angle: the same solar energy is distributed over an ever larger area. Therefore, the greater the distance from the equator, the cooler it becomes. This creates regions with different climates, the climatic zones.

According to the strength of the solar radiation, four different climate zones can be divided on the mainland of the earth: The tropics around the equator, the subtropics (from the Latin word “sub” for “under”) between the 23rd and 40th parallel, the temperate Zone of our latitudes and the polar regions around the north and south poles. Like belts, they draw these climatic zones around the earth in an east-west direction.

The climate does not only depend on the latitude, other influences also play a role. There is snow on Kilimanjaro, even though it is in the tropics. The fact that its summit is icy is due to the fact that the temperature drops with increasing altitude. The mountain climate is therefore always cooler than lower lying areas.

The distance to the sea also has an impact on the climate: water can store solar heat longer than the mainland. It is also warming up more slowly than the country. As a result, the sea water acts like a buffer for temperatures. The climate is therefore mild near the coast. In the interior of the country, this heat balance is missing and the climate is continental, with temperatures fluctuating much more than in the maritime climate near the sea.

From the rainforest to the tundra - vegetation zones

Trees and deciduous forests can do well in cool and humid areas. In contrast, where it is particularly hot and dry, hardly anything grows: deserts are forming there. Only plants that are as well adapted to this extreme climate as cacti have a chance to survive here.

Plants depend on the climate: where which species are at home is mainly determined by the temperature and the amount of precipitation. That is why there are many different regions on earth with certain plant communities: the vegetation zones. Because the type of vegetation depends on the climate, these vegetation zones, similar to the climatic zones, run roughly parallel to the equator.

The rainforest in the always humid tropics is one of the typical vegetation zones. With increasing distance from the equator, the grasslands of the savannah, on which trees and bushes also thrive, are the typical vegetation. In the direction of the poles follow the subtropics with deserts and semi-deserts, the special vegetation of the alternating and always humid subtropics, the deciduous and mixed forests of the temperate latitudes and the coniferous forests of the cold temperate zone. In the areas around the poles, only particularly hardened bushes, mosses and lichens grow. This last vegetation zone before the polar ice desert is called tundra.

The boundaries of the vegetation zones are not always easy to recognize, their transitions are fluid. This is also due to the fact that humans influence the plant world: by clearing forests, cultivating the land and building cities, they change the original vegetation. Those who want to describe which plants are actually growing at the moment also speak of eco-zones when they are classified.