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Clim. Past Discuss., 8, 1615-1651, 2012
www.clim-past-discuss.net/8/1615/2012/ doi:10.5194/cpd-8-1615-2012 © Author(s) 2012. This work is distributed under the Creative Commons Attribution 3.0 License. |
Climate warming and vegetation response at the end of Heinrich event 1 (16 700–16 000 cal yr BP) in Europe south of the Alps
1Oeschger Centre for Climate Change Research and Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland
2Palaeoecology, Department of Physical Geography, Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, CD 3584 Utrecht, The Netherlands
Abstract. Chironomids preserved in a sediment core from Lago di Origlio (416 m a.s.l.), a lake in the foreland of the Southern Swiss Alps, allowed quantitative reconstruction of Late Glacial and early Holocene temperatures using a combined Swiss-Norwegian temperature inference model based on chironomid assemblages from 274 lakes. We reconstruct July air temperatures of ca. 10 °C between 17 300 and 16 000 cal yr BP, a rather abrupt warming to ca. 12.0 °C at ca. 16 500–16 000 cal yr BP, and a strong temperature increase at the transition to the Bølling/Allerød Interstadial with average temperatures of about 14 °C. During the Younger Dryas and earliest Holocene very similar temperatures are reconstructed as for the interstadial. The rather abrupt warming at 16 500–16 000 cal yr BP is consistent with sea-surface temperature as well as speleotherm records, which indicate a marked Pre-Bølling warming after the end of Heinrich event 1 in southern Europe and the Mediterranean Sea. The pollen record of Origlio and other sites from southern Switzerland and northern Italy indicate an early reforestation of the lowlands prior to the large-scale afforestation at the onset of the Bølling period at 14 700 cal yr BP in Central Europe. Our results suggest that these afforestation processes in the formerly glaciated areas of southern Switzerland and Northern Italy have been promoted by increasing temperatures.
Citation: Samartin, S., Heiri, O., Lotter, A. F., and Tinner, W.: Climate warming and vegetation response at the end of Heinrich event 1 (16 700–16 000 cal yr BP) in Europe south of the Alps, Clim. Past Discuss., 8, 1615-1651, doi:10.5194/cpd-8-1615-2012, 2012.