Sweden Hydrography and Climate

Sweden Hydrography and Climate

TERRITORY: HYDROGRAPHY

As mentioned, the current hydrographic system of Sweden results from the Quaternary glaciation, which is responsible for the youthful profiles of the rivers and the many lake basins: 8% of the national surface is occupied by lakes, and in general the water wealth has made so that Sweden is one of the countries in which the hydroelectric industry is most developed. Apart from the streams that are innervated radially from Småland, the rivers originate from the western reliefs, originating for the most part from a lake carved by ice in the mountainous side, and descend to the Baltic with a mostly parallel course, from NW to SE, forming a series of rapids and waterfalls; numerically significant, they are modest in terms of length (on average from 300 to 500 km) and basin width (10,000-30,000 km²). Their scope is quite variable, recording the floods in spring and early summer, coinciding with the melting of the snow, while late summer and winter are low periods. Among the main rivers, are, from N to S, the Lule (Luleälv: älv means river), the Ume (Umeälv), the Ångerman (Ångermanälv), the Indals (Indalsälv) and the Dal (Dalälv), all tributaries of the Baltic Sea; Port and woodworking centers have developed at their mouths, as Swedish rivers, especially the Norrland ones, are widely used for timber floating. Among the many lakes, the Vänern, third in Europe (5585 km²), whose emissary Göta flows into the Kattegat, the Vättern (1912 km²), which communicates with the Baltic Sea as well as the Mälaren, stand out for their size. (1140 km²), on whose shores – as well as on various islands – Stockholm is partly built.

TERRITORY: CLIMATE

The considerable latitudinal development of Sweden determines strong climatic variations from the South to the North of the country; however, these variations are particularly sensitive in the interior, because in the peripheral belt the mitigating action of the Baltic Sea and the Atlantic Ocean is felt almost everywhere, on whose influences the rainfall also largely depends. There is thus a positive thermal anomaly, very marked in winter, so much so that in Stockholm the January average is around -3 ° C, a value that, for example, for the Russian city of Perm, located at a slightly lower latitude. lower, it drops to –15 ° C. The maximum climatic rigors naturally correspond to central Lapland. The average annual temperature is 7-8 ° C in the South and oscillates between –1 ° C and –2 ° C in the North; the winter differences between the two ends of the country are 0 ° C and -14 ° C in January, while the summer differences in July are less marked, of 16 ° and 14 ° C. Summer is generally short, but in the extreme northern regions the high latitude gives rise to the phenomenon of ” midnight Sun ”: For example in Karesuando, at latitude 68 ° N, the Sun remains above the horizon from the end of March to mid-July (on the other hand, winter nights also last 24 hours). Visit insidewatch.net for practical travel information for your trip to Sweden.

The period of the cold season is very prolonged; in the North, the ice persists from October to May and in winter prevent navigation in the Gulf of Bothnia, while the waters off the western and southern coasts are generally clear. Precipitation is relatively abundant, with peaks predominantly in summer and autumn, and much of it falls in the form of snow. The average for Sweden is 800-1000 mm of rain per year, more accentuated in the southern and western regions; in the extreme eastern area of ​​Lapland, on the border with Finland, it also falls below 500 mm per year while on the north-western reliefs, that exercise an action of capturing the masses of sea air, the maximum values ​​are obtained, with 1500 mm per year. The natural vegetation, which reoccupied Sweden after the glaciations, is still present over large areas of the country, especially in Norrland, where the forest of conifers, pines and firs, mixed with birch trees, which passes through the extreme northern regions and on the reliefs, to the subarctic tundra; in the south of the country, where the cultivated fields have a large extension, there is a beautiful broad-leaved forest with linden trees, oaks, elms, ash trees and, in Scania, beech trees. where the forest of conifers, pines and firs, mixed with birch trees predominates, which passes through the subarctic tundra in the extreme northern regions and on the reliefs; in the south of the country, where the cultivated fields have a large extension, there is a beautiful broad-leaved forest with linden trees, oaks, elms, ash trees and, in Scania, beech trees. where the forest of conifers, pines and firs, mixed with birch trees predominates, which passes through the subarctic tundra in the extreme northern regions and on the reliefs; in the south of the country, where the cultivated fields have a large extension, there is a beautiful broad-leaved forest with linden trees, oaks, elms, ash trees and, in Scania, beech trees.

Sweden Hydrography and Climate