The quantity and characteristics of sediment deposited in lakes are affected by climate to varying extents. As sediment is deposited, it provides a record of past climatic or environmental conditions. However, determining a direct relationship between specific climatic variables and measurable sediment properties, for instance between temperature and sediment optical reflectance, is complex. In this study, we investigate the suitability of sediment reflectance, recorded as sediment pixel intensity (PxI), as a paleoclimate proxy at a large ice-contact lake in southern Patagonia, Lago Argentino. We also evaluate whether sediment PxI can be used to investigate the present-day climatic drivers of sedimentation across Lago Argentino. First, we show that sediment PxIs relate to underlying sediment composition, and are significantly correlated with XRF-derived major element composition. Secondly, we find that PxIs correlate with both austral summer temperatures and wind speeds, but not with precipitation. PxI timeseries reach the
- Award ID(s):
- 1714614
- NSF-PAR ID:
- 10482963
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Quaternary Science Reviews
- Volume:
- 304
- Issue:
- C
- ISSN:
- 0277-3791
- Page Range / eLocation ID:
- 108009
- Subject(s) / Keyword(s):
- ["Southern Annular Mode","Patagonia","Paleoclimate","Spectral analysis","Lago Argentino","lake core"]
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.quascirev.2023.108009
