A leaf wax hydrogen isotope record of paleoprecipitation from Lake Chalco, Mexico
Abstract
The Basin of Mexico Drilling Project aims to reconstruct a high-resolution lacustrine record of subtropical North American environmental change. As part of this project, here we present hydrogen isotope composition of plant leaf-waxes (δDwax) from the Lake Chalco sedimentary record spanning multiple glacial/interglacial cycles. δDwax is widely used as a proxy for estimating the hydrogen isotope composition of past precipitation. However, the difference between plant photosynthetic pathways and relative humidity can exert influence on δDwax, thereby introducing bias in the utilization of δDwax. To compensate for the potential offsets from plant types and improve the application of δDwaxas a paleoprecipitation proxy, we performed a modern calibration study of δDwax using surface sediments from ~80 lakes in Mexico and Guatemala. In this study, we applied the regional calibration to downcore reconstruction of the Lake Chalco sediment core, giving evidence for paleoprecipitation variability on glacial/interglacial time scales, enhancing our understanding of long-term climate variability in the North American subtropics.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMPP31D1670L
- Keywords:
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- 1616 Climate variability;
- GLOBAL CHANGE;
- 4943 Paleolimnology;
- LIMNOLOGY;
- 4914 Continental climate records;
- PALEOCEANOGRAPHY;
- 4954 Sea surface temperature;
- PALEOCEANOGRAPHY