Reconstructing hydrological variability in Lake Baikal during MIS 11: an application of oxygen isotope analysis of diatom silica

Abstract

In this paper we reconstruct hydrological variability in Lake Baikal during Marine Isotope Stage 11 (MIS 11) (427–362 ka BP) from oxygen isotope analysis of diatom silica. Highest δ18Odiatom values are found during MIS 11.3, highlighting the dominance of hydrological input from rivers flowing into the south and central basins of Lake Baikal, especially the Selenga River. Hydrological input from south basin rivers dominated for over 30 ka. However, there is evidence from both biogenic silica and δ18Odiatom records for an abrupt cooling event at ca. 390 ka BP. Stadial conditions at this time are coincident with an iceberg discharge event into the North Atlantic. The decline in δ18Odiatom values suggests increasing proportion of hydrological input from rivers to the north of Lake Baikal, due to greater influence of winter precipitation and snow‐melt. After a period of interstadial conditions during the early stages of MIS 11.1, biogenic silica and δ18Odiatom values decline, mirroring the slow growth in Northern Hemisphere ice sheets. Despite rigorous cleaning procedures, palaeoclimatic inferences need to be treated with caution due to contamination of the δ18Odiatom record; during stadial and glacial periods, contamination of the δ18Odiatom record is even more significant. © Natural Environment Research Council (NERC) copyright 2008. Reproduced with the permission of NERC. Published by John Wiley & Sons, Ltd.

Climate in continental interior Asia during the longest interglacial of the past 500 000 years: the new MIS 11 records from Lake Baikal, SE Siberia

“…The apparent duration of MIS 11 has been discussed previously in a single BDP-96 record based on past changes in diatom productivity and biogenic silica accumulation (Prokopenko et al, 2001a;Karabanov et al, 2003;Mackay et al, 2008). By comparing prior results with the new MIS 11 pollen record, here test the extent to which the MIS 11 diatom/BioSi peak actually represents true interglacial conditions in the region.…”

“…2), of which BDP-96-2 is the most complete and BDP-99 has the highest resolution. Previous studies touching on or specifically dedicated to the MIS 11 proxy responses dealt with biogenic silica content (BioSi) and/or diatoms (Prokopenko et al, 2001a;Karabanov et al, 2003;Mackay et al, 2008).…”

“…Orbital parameter solutions are from Berger et al (1993) and Laskar et al (2004). The δ 18 O of Baikal diatoms (Mackay et al, 2008) records the cooling at the end of the MIS 11 interglacial (purple arrow), and, possibly, earlier, less significant cooling episodes (blue arrows). (Prokopenko et al, 2001a).…”

Oxygen isotope composition of diatoms from sediments of Lake Kotokel (Buryatia)

“…Specifically, δ 18 O diatom data from Lake Baikal revealed general trends in the system responses to global change (Kalmychkov et al, 2007;Mackay et al, 2008Mackay et al, , 2011Mackay et al, , 2013Morley et al, 2005). However, detailed climate reconstructions for the last glacial-interglacial cycle are impeded by poor isotopic age constraints (KalmyRussian Geology and Geophysics 57 (2016) 1213-1221 chkov et al, 2007) and low temporal resolution (Morley et al, 2005;Mackay et al, 2011) of the records.…”

OXYGEN ISOTOPE COMPOSITION OF DIATOMS FROM SEDIMENTS OF LAKE KOTOKEL (Buryatia)

“…O diatom data from Lake Baikal revealed general trends in the system responses to global change (Kalmychkov et al, 2007;Mackay et al, 2008Mackay et al, , 2011Mackay et al, , 2013Morley et al, 2005). However, detailed climate reconstructions for the last glacial-interglacial cycle are impeded by poor isotopic age constraints (KalmyRussian Geology and Geophysics 57 (2016) 1213-1221 chkov et al, 2007) and low temporal resolution (Morley et al, 2005;Mackay et al, 2011) of the records.…”