NEOGLACIATION, GLACIER-DAMMED LAKES, AND VEGETATION CHANGE IN NORTHWESTERN BRITISH-COLUMBIA, CANADA

An integrated geomorphic, stratigraphic, paleoecological, and geochron ological study of a system of linked valley glaciers and ice-dammed la kes has provided insights into the Neoglacial history and climate of t he northern Coast Mountains of British Columbia. Cores collected fi om a small lake in the glacier foreland of Berendon Glacier and pits dug in a nearby fen record Little Ice Age and earlier Neoglacial advances . AMS and conventional radiocarbon dating of fossil plant material fro m these sites, supplemented by dendrochronological data, indicate that the Little Ice Age began more than 500 yr ago and peaked in the early 17th century. A middle Neoglacial advance of comparable extent occurr ed about 2200 to 2800 yr ago. The chronology of Neoglacial advances is generally similar to that at other sites in western Canada, although the Little Ice Age may have peaked as much as 100 yr earlier in our st udy area than elsewhere. The Little Ice Age advances are also broadly synchronous with those in other parts of the world, suggesting that th ey were caused by global changes in climate.