Pollen stratigraphy of a core taken from a fen at Fundo Nueva Braunau (40 degrees 17.49'S, 73 degrees 04.83'W), situated 2 km beyond the western border of Llanquihue-age glacial drift, spans an age range from an estimated 60 000-70 000 BP to about 14 000 C-14 yr BP (marine Oxygen Isotope Stages 4-2). The location at present is in the contact zone of Valdivian Evergreen Forest and Lowland Deciduous Beech Forest. Early and late in the pollen record, as indicated by assemblages of southern beech (Nothofagus dombeyi type) and grass (Gramineae), the site was located in Subantarctic Parkland. Intervening assemblages represent expansion of Valdivian-North Patagonian Evergreen Forest (> 49 355 to about 40 000 C-14 yr BP) and North Patagonian Evergreen Forest-Subantarctic Parkland (approximately 40 000 to 30 000 C-14 yr BP).Climate over the time span was under the storm regime of the Southern Westerlies and apparently uninterruptedly wet. When Subantarctic Parkland expanded, cold conditions with summer temperatures estimated at 8-9 degrees C (7 degrees C lower than present) resulted in episodes of glacier maxima. Climate moderated during the period of forest expansion, at which time glaciers were in a state of recession. Contrasting with the continuously wet climate of the Lake District for the period of record, climate in semi-arid-arid, subtropical Chile underwent extended intervals of precipitation. Data from both the terrestrial and marine realm implicate the Southern Westerlies as the cause of intensified storm activity at lower latitudes. Copyright (C) 2000 John Wiley & Sons, Ltd.
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