Karl-Dag Vorren (e-mail: email@example.com), University of Tromsø, Department of Biology, NO-9037 Tromsø, Norway; Ellen Elverland, Tromsø Museum, University of Tromsø, NO-9037 Tromsø, Norway; Maarten Blaauw, School of Geography, Archaeology and Palaeoecology, Queen's University, Belfast, UK; Erling K. Ravna, University of Tromsø, Department of Geology, NO-9037 Tromsø, Norway; Christin A. H. Jensen, Museum of Archaeology, Department of Cultural Heritage, NO-4002, Stavanger, Norway
Vegetation and climate c. 12 300–9000 cal. yr BP at Andøya, NW Norway
Article first published online: 12 FEB 2009
© 2009 The Authors, Journal compilation © 2009 The Boreas Collegium
Volume 38, Issue 3, pages 401–420, August 2009
How to Cite
VORREN, K.-D., ELVERLAND, E., BLAAUW, M., RAVNA, E. K. and JENSEN, C. A. H. (2009), Vegetation and climate c. 12 300–9000 cal. yr BP at Andøya, NW Norway. Boreas, 38: 401–420. doi: 10.1111/j.1502-3885.2008.00081.x
- Issue published online: 20 JUL 2009
- Article first published online: 12 FEB 2009
- received 30th September 2008, accepted 13th November 2008.
Owing to proximity of the North Atlantic Stream and the shelf, the Andøya biota are assumed to have responded rapidly to climatic changes taking place after the Weichselian glaciation. Palynological, macrofossil, loss-on-ignition, tephra and 14C data from three sites at the northern part of the island of Andøya were studied. The period 12 300–11 950 cal. yr BP was characterized by polar desert vegetation, and 11 950–11 050 cal. yr BP by a moisture-demanding predominantly low-arctic Oxyria vegetation. During the period 11 050–10 650 cal. yr BP, there was a climatic amelioration towards a sub-arctic climate and heaths dominated by Empetrum. After 10 650 cal. yr BP the Oxyria vegetation disappeared. As early as about 10 800 cal. yr BP the bryozoan Cristatella mucedo indicated a climate sufficient for Betula woodland. However, tree birch did not establish until 10 420–10 250 cal. yr BP, indicating a time-lag for the formation of Betula ecotypes adapted to the oceanic climate of Andøya. From about 10 150 to 9400 cal. yr BP the summers were dry and warm. There was a change towards moister, though comparatively warm, climatic conditions about 9400 cal. yr BP. The present data are compared with evidence from marine sediments and the deglaciation history in the region. It is suggested that during most of the period 11 500–10 250 cal. yr BP a similar situation as in present southern Greenland existed, with birch woodland in the inner fjords near the ice sheet and low-arctic heath vegetation along the outer coast.