In:
The Holocene, SAGE Publications, Vol. 19, No. 6 ( 2009-09), p. 873-881
Abstract:
We present a pigment-based quantitative high-resolution (five years) austral summer DJF (December to February) temperature reconstruction for Central Chile back to AD 850. We used non-destructive in situ multichannel reflection spectrometry data from a short sediment core of Laguna Aculeo (33°50′S/70°54′W, 355 m a.s.l., central Chile). Calibration-in-time (period AD 1901—2000, cross-validated with split periods) revealed robust correlations between local DJF temperatures and total sedimentary chlorin (relative absorption band depth (RABD) centred in 660—670 nm RABD 660;670 : r=0.79, P 〈 0.01; five-years triangular filtered) and the degree of pigment diagenesis ( R 660nm/670 nm : r=0.82, P 〈 0.01; five-years triangular filter). Root Mean Squared Error values are small (between 0.24 and 0.34°C) suggesting that most of the reconstructed decadal-scale climate variability is significant. Our data provide quantitative evidence for the presence of a Medieval Climate Anomaly (in this case, warm summers between AD 1150 and 1350; Δ T = +0.27 to +0.37°C with respect to (wrt) twentieth century) and a very cool period synchronous to the ‘Little Ice Age’ starting with a sharp drop between AD 1350 and AD 1400 (−0.3°C/10 yr, decadal trend) followed by constantly cool (Δ T = −0.70 to −0.90°C wrt twentieth century) summers until AD 1750. The structure of variability is consistent in great detail with annually resolved tree-ring based warm-season temperature and river discharge reconstructions from northern Patagonia (42°S) for the past 400 years, with qualitative climate reconstructions from Andean glacier fluctuations, and with hydrological changes in Patagonian lake sediment records.
Type of Medium:
Online Resource
ISSN:
0959-6836
,
1477-0911
DOI:
10.1177/0959683609336573
Language:
English
Publisher:
SAGE Publications
Publication Date:
2009
detail.hit.zdb_id:
2027956-5
SSG:
14
SSG:
3,4
