Temperature, precipitation, and vegetation changes in the Eastern Mediterranean over the last deglaciation and Dansgaard-Oeschger events ...
We here estimate past temperature and hydroclimate variations in eastern Anatolia for marine isotope stages 4 to 1 (MIS4 to MIS1) respectively using branched glycerol dialkyl glycerol tetraethers (brGDGTs) and the hydrogen isotopic composition of n-C29 leaf-wax n-alkanes (δ2Hwax) stored in the sedim...
Main Authors: | , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
ETH Zurich
2021
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Subjects: | |
Online Access: | https://dx.doi.org/10.3929/ethz-b-000493872 http://hdl.handle.net/20.500.11850/493872 |
Summary: | We here estimate past temperature and hydroclimate variations in eastern Anatolia for marine isotope stages 4 to 1 (MIS4 to MIS1) respectively using branched glycerol dialkyl glycerol tetraethers (brGDGTs) and the hydrogen isotopic composition of n-C29 leaf-wax n-alkanes (δ2Hwax) stored in the sedimentary record of Lake Van (Turkey). Our millennial-scale lipid biomarker records reflect warm and wet conditions during interstadials/interglacials and colder and dryer periods with increased evapotranspiration and aridity during stadials/glacials. The degree of methylation of the 5-methyl brGDGTs (MBT´5me) indicates increasing mean annual air temperatures (MAT) during stadial/interstadial transitions, that characterize Dansgaard-Oeschger events, and during the last glacial termination. Based on the effects of changes in precipitation amount on apparent enrichment factors between the δ2H of the C29 n-alkanes and δ2H of precipitation, a total increase in annual precipitation of about 200 mm during transitions from ... : Palaeogeography, Palaeoclimatology, Palaeoecology, 577 ... |
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