Abstract
High-resolution, quantitative temperature records are valuable for placing recent warming in the context of long-term, natural climate variability. Here we use biogenic silica (BSi) concentrations preserved in lacustrine sediment from an oligotrophic lake to quantitatively reconstruct air temperature at Hallet Lake in south-central Alaska. Mean June through August temperature measured over the past 80 yr at Valdez (Alaska) correlate with BSi from Hallet Lake (r = 0.87, p = 0.01). We chose anested function to model the non-linear relation between summer temperature and BSi in the calibration data set, and to reconstruct temperature for the past 2 ka. Our BSi-inferred temperature reconstruction shows synchronous changes with independent paleoclimatic proxies for southern Alaska, and provides evidence for a greater rate and magnitude of 20th century temperature warming at Hallet Lake than recorded by other quantitative temperature proxies in the region.
Original language | English (US) |
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Article number | L05709 |
Journal | Geophysical Research Letters |
Volume | 35 |
Issue number | 5 |
DOIs | |
State | Published - Mar 16 2008 |
ASJC Scopus subject areas
- Geophysics
- Earth and Planetary Sciences(all)