Weichselian glaciation

Europe during the Weichselian and Würm cold periods

The last glacial period and its associated glaciation is known in Northern Europe as the Weichselian glaciation, Weichselian ice age (German: Weichsel-Eiszeit), Vistulian glaciation, Weichsel[1] or, less commonly, the Weichsel glaciation, Weichselian cold period (Weichsel-Kaltzeit), Weichselian glacial (Weichsel-Glazial), Weichselian Stage or, rarely, the Weichselian complex (Weichsel-Komplex). In the Alpine region it corresponds to the Würm glaciation. It was characterised by a large ice sheet that spread out from the Scandinavian Mountains and extended as far as the east coast of Schleswig-Holstein, the March of Brandenburg and North Russia.

In Northern Europe it was the youngest of the glacials of the Pleistocene ice age. The preceding warm period in this region was the Eemian interglacial. The last cold period began about 115,000 years ago and ended 11,700 years ago.[2] Its end corresponds with the end of the Pleistocene epoch and start of the Holocene.

Naming in other parts of the world

In other regions the glaciations of the last glacial period are given other names: for example that in the Alpine region is called the Würm glaciation, in the British Isles it is the Devensian glaciation and in North America, the Wisconsin glaciation.[3][4]

Sequence and subdivisions of the Weichselian

The earth at the last glacial maximum. Illustration based on: Ice age terrestrial carbon changes revisited by Thomas J. Crowley (Global Biogeochemical Cycles, Vol. 9, 1995, pp. 377-389).

About 115,000 years ago[2] average temperatures dropped markedly and warmth-loving woodland species were displaced. This significant turning point in average temperatures marked the end of the Eemian interglacial and start of the Weichselian glacial stage. It is divided into three sections, based on the temperature variation: the Weichselian Early Glacial,[5][6] the Weichselian High Glacial[5] (also Weichselian Pleniglacial[6]) and the Weichselian Late Glacial.[6] During the Weichselian, there were frequent major variations in climate in the northern hemisphere, the so-called Dansgaard-Oeschger events.

The Weichsel Early Glacial (115,000 - 60,000 BC) is in turn divided into four stages:

In the Weichselian High Glacial (57,000 - c. 15,000 BC) the ice sheet advanced into North Germany. In this period, however, several interstadials have been documented.

The short "Weichselian Late Glacial" (12,500 - c. 10,000 BC) was the period of slow warming after the Weichselian High Glacial. It was however again interrupted by some colder episodes.

Following the last of these cold periods, the Younger Dryas, the Weichselian Glacial ended with an abrupt climb in temperature around 9,660 ± 40 BC.[7] This was the start of our present interglacial, the Holocene.

In addition to the above subdivisions the depositions of the Weichselian Late Glacial following the retreat of the ice sheet are divided into four stages: the Germanic Glacial (Germaniglazial) (Germany becomes ice-free), the Danish Glacial (Daniglazial) (Denmark becomes ice-free), The Gotland Glacial (Gotiglazial) (Gotland becomes ice-free) and the Finnish Glacial (Finiglazial) (Finland and Norway become ice-free).[8]

  • Maximum extent of the ice (Brandenburg Stage) during the Weichselian in North Germany (red line)
  • greatest extent of the older Saalian glaciation (yellow line)
    • . Note that the coastlines are modern, coastlines during the Weichselian were different as sea level was lower.

    See also

    References

    1. ↑ Whittow, John (1984). Dictionary of Physical Geography. London: Penguin, 1984, p. 580. ISBN 0-14-051094-X.
    2. 1 2 Litt et al. (2007: pp.45ff)
    3. ↑ F.J. Monkhouse Principles of Physical Geography, London: University of London Press, 1970 (7th edn.), p. 254. SBN 340 09022 7
    4. ↑ Whittow, John (1984). Dictionary of Physical Geography. London: Penguin, 1984, p. 265. ISBN 0-14-051094-X.
    5. 1 2 Wolfgang Schirmer, Quaternary field trips in central Europe, Volume 1, Pfeil, 1995, p. 375. ISBN 978-39-238-7191-9
    6. 1 2 3 John Dodson (ed.), Earth Systems and Society, New York, London, etc., Springer, 2010 p. 173. ISBN 978-90-481-8716-4
    7. ↑ Friedrich M, Kromer B, Spurk M, Hofmann J, Kaiser KF.(1999): Paleo-environment and radiocarbon calibration as derived from Late Glacial/Early Holocene tree-ring chronologies. In: Quaternary International 61:27–39.
    8. ↑ Karl N. Thome (1998), Einführung in das Quartär. Das Zeitalter der Gletscher (in German), Berlin: Springer-Verlag, pp. 72

    Literature

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