Permafrost

Circum-Arctic Map of Permafrost and Ground-Ice Conditions and the Maps of Geocryological
Regions and Classifications in China. While there are many other variables that influence the
permafrost distribution, this comparison could reveal potential systematic relationship between
rainfall and permafrost.
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Palaeoenvironmental Changes on the South-eastern Margin of the
Tibetan Plateau:a Pollen-data Based Analysis
Annette Kramer 1,2 , Ulrike Herzschuh 1 , Steffen Mischke 2
(1. Alfred Wegener Institute for Polar and Marine Research, Potsdam Germany
2. Freie Universitaet Berlin, Institute of Geological Sciences, Berlin Germany)
Abstract: An 18 m long sediment core from Lake Naleng in the south-eastern part of the
Qinghai-Xizang Plateau (present-day precipitation:~ 800mm) was examined to reconstruct the
vegetation and climate history of the region, considering the composition of fossil pollen. To
retrace precipitation patterns quantitatively, a pollen-precipitation transfer function was applied.
The region is influenced by the Indian Monsoon; a shift in the intensity of the monsoon
circulation is therefore detectable.
The age of the core base was determinate by means of AMS-Dating to 16.5 ka cal BP.
Findings from qualitative and quantitative analysis show a periglacial vegetation,
composed of alpine cushion plants and species which indicate perturbed conditions, for the
beginning of the Late Glacial.
The reconstructed precipitation shows an annual amount of ca. 300-400 mm. Climate
conditions stabilised and alpine meadows established around the lake during the later Late
Glacial. The Pleistocene/Holocene transition is marked by a rise of arboreal pollen (mainly
Abies and Betula).
Forests were reconstructed for the first half of the Holocene, pointing to an enhanced
summer monsoon for this period with annual rainfall of about 800 mm. An increase in alpine
herb and shrub taxa and a decrease of arboreal taxa during the Late Holocene indicate a
decrease of the forest vegetation in the area.
Key words: Tibetan Plateau, Pollen Analysis, palaeoclimate, transfer-functions, Monsoon
Cryolithological features of Quaternary sediments on the
Lena-Kénkémé interfluve, Central Yakutia
Christine Siegert 1 , Valery Basylev 2
(1. Alfred Wegener Institute for Polar and Marine Research, Research Unit Potsdam, Germany; 2. Melnikov
Permafrost Institute, Yakutsk, Russia)
Abstract: Central Yakutia has an extreme continental climate with an annual range of
temperature of more than 100°C. In Yakutsk, temperature extremes can reach –64°C in winter