Europe - Last ice age (approx. 20,000 years ago)
Agriculture and landscape change
978-3-14-100890-6 | Page 55 | Ill. 2
Overview
Europe's climate history is characterised by cold and warm periods. The last significant cold period, when large parts of the European continent were covered with ice and snow, was about 20,000 years ago. Average temperatures 4 to 8 °C below those of our century led to massive advances of the Alpine glaciers and to movements of the Scandinavian inland ice masses towards the south. These profound climatic changes led to a shift of climatic and vegetation zones towards the equator. Tundra became predominant in western and central Europe, while boreal coniferous, deciduous and mixed forests covered much of the Mediterranean. Fine calcareous dust, composed of a variety of minerals and called loess, was blown away by the inorganic deposits created by the ice, such as moraine and gravel fields and periglacial debris accumulations. Despite the inhospitable living conditions, human communities of hunter-gatherers lived in Europe during this period of the Stone Age.
The map shows the European continent during this last ice age about 20,000 years ago.
The most recent glacial periods
The last glacial epoch, known as the Pleistocene, began more than 2,500,000 years ago and ended with the deterioration of the solid ice cap formed during the Weichsel-Würm glacial period, which still covered large portions of the Scandinavian mountains some 9,000 years ago. The four most recent glacial periods in the northern Alpine Foothills are named for rivers and referred to as the Guenz, Mindel, Riss and Würm periods.A glacial period corresponding to the Guenz glacial has not been identified with certainty in northern Germany. Subsequent glacial advances during the Elster, Saale and Weichsel periods presumably obliterated these early traces of glaciation.
Topographical impacts
The major glacial advances of the Pleistocene epoch had a significant impact on the topography, with noticeably different effects in northern Germany and the Alpine region. In the Nordic glacial, the ice masses advancing from Scandinavia moved accumulations of fine and very coarse material, including foundlings. These accumulations were reformed by erosion and glacial valleys. Large portions of the pre-glacial topographic relief were covered by morainic rubble. In the Alps, glaciers had a clearing effect which created the characteristic Alpine relief. The downward shift of the climatic snow line promoted the expansion of valley glaciers, the tongues of which also covered the Alpine Foothills. Terminal moraines mark the farthest points of glacial advance today.
Exhibiting a basic pattern similar to that of northern Germany, a remarkably regular accumulation of forms, known as the glacial series, took shape in the Alpine Foothills. During each period of glacial advance, ice spread over the deposits left by the last preceding glacial period. A basal moraine pushing rubble ahead of itself accumulated beneath the glacier. A terminal moraine was formed along the ice margin (interstadial epoch), with rubble fields (outwash plains in northern Germany) deposited by meltwater in front of them. The picture was completed by drainage gullies (glacial valleys in northern Germany), in which glacial meltwater was captured. In northern Germany, these merged with the water from streams coming from the South and flowed along the ice margin to the sea.
