A review of multi-proxy data for the younger dryas in Atlantic Canada

• Published in: Quaternary science reviews Vol. 14; no. 9; pp. 813 - 821
• Main Authors: Mayle, Francis E., Cwynar, Les C.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1995
• ISSN: 0277-3791; 1873-457X
• DOI: 10.1016/0277-3791(95)00063-1

Multi-proxy data obtained from lake sediments and buried organic sequences is reviewed and discussed as evidence for the Younger Dryas cooling event in Atlantic Canada. Sedimentological studies indicate that lake basins were subject to increased erosion due to climate cooling, while glacial and periglacial sediments overlying peats have been attributed to the effects of small Younger Dryas ice-caps building up in highland areas of Nova Scotia. Pollen evidence from over 30 sites shows two broad patterns of Lateglacial vegetation change in the region. The Younger Dryas cooling caused the replacement of closed boreal forest by shrub-tundra in southern New Brunswick and central mainland Nova Scotia, and the replacement of shrub-tundra by herb-tundra in central New Brunswick, northern Nova Scotia and Newfoundland. Chironomid data indicate that the Younger Dryas was marked by a drop in summer lake surface-water temperatures of ca. 6°C, while diatom data suggest that marked limnological changes also occurred. Based on AMS 14C dates from terrestrial plant macrofossils of 8 sites, the Younger Dryas event in Atlantic Canada lasted from ca. 10,830 to 10,000 BP. These dates match most of those from northwest and central Europe, suggesting that this climatic event affected the entire North Atlantic region essentially simultaneously.