A 50,000-yr pollen record from Chile of South American millennial-scale climate instability during the last glaciation

Citation

Heusser L, Heusser C, Kleczkowski A & Crowhurst SJ (1999) A 50,000-yr pollen record from Chile of South American millennial-scale climate instability during the last glaciation. Quaternary Research, 52 (2), pp. 154-158. https://doi.org/10.1006/qres.1999.2069

Abstract
High-resolution (∼≤100 yr sampling interval) Chilean pollen data between ∼10,000 and 60,000 cal yr B.P. exhibit systematic fluctuations in Subantarctic Parkland development. These variations are dominated by a 30,000-40,000-yr cycle similar to that in the Northern Hemisphere GISP2 δ18O data and other climatic records. Both Chilean and GISP2 data show oscillations in the 5000-12,000 and 1000-3000-yr period bands. The coherence is, however, generally low, and distribution of power spectra differs, with the dynamics of the pollen assemblage dominated by a combination of 12,000- and 5000-yr cycles. We suggest a preferential nonlinear response of Chilean vegetation to climatic forcing and interhemispheric differences as possible mechanisms underlying the resemblances and dissimilarities between both records.

Keywords
pollen; South America; millennial-scale paleoclimate cycles; interhemispheric comparison; Quaternary

Journal
Quaternary Research: Volume 52, Issue 2