The Holocene lipid biomarker record of climate and hydrological change at Lake El'gygytgyn, NE Russia

International deep drilling operations have recently recovered sediment cores from Lake El’gygytgytn, a 3.6 Ma old impact crater lake located in central Chukota, NE Russia. Pilot cores recovered from the central part of the lake in 2003 comprise the last 340 ka, providing new insights into Arctic climate evolution and enhancing our capacity to identify and quantify the function of the arctic region in modulating past changes under various climate forcing conditions. Variations in hydrological processes in the Arctic have major implications not only for arctic terrestrial and marine ecosystems, but also for the cryosphere and global ocean. Analysis of the deuterium/hydrogen isotopic ratio of specific organic biomarkers allows reconstruction of past hydrologic conditions, thereby providing a powerful tool for reconstructing past terrestrial Arctic climate changes. δD measurements of individual sedimentary fatty acids representing aquatic and terrestrial sources (e.g. aquatic, δDAQ: nC20, nC22; terrestrial, δDTER: nC26, nC28, nC30) show significant variation (~ 100 ‰) between glacial-interglacial intervals as well as variability on centennial timescales (~200 yr resolution). Isotopic enrichment in both the δDAQ and δDTER records during the Early Holocene suggests increasing temperatures and decreasing continentality comparable with the Greenland ice core δDGRIP record. Expanding this record provides a unique opportunity to compare a high latitude continental site with Greenland ice core records and will allow more a detailed assessment of global teleconnections and paleohydrological changes within this climatically sensitive Arctic region.