Palaeoclimate reconstruction on Big Lyakhovsky Island, north Siberia—hydrogen and oxygen isotopes in ice wedges

Abstract

Late Quaternary permafrost deposits on Big Lyakhovsky Island (New Siberian Islands, Russian Arctic) were studied with the aim of reconstructing the palaeoclimatic and palaeoenvironmental conditions of northern Siberia. Hydrogen and oxygen stable isotope analyses are presented for six different generations of ice wedges as well as for recent ice wedges and precipitation. An age of about 200 ka BP was determined for an autochtonous peat layer in ice‐rich deposits by U/Th method, containing the oldest ice wedges ever analysed for hydrogen and oxygen isotopes. The palaeoclimatic reconstruction revealed a period of severe winter temperatures at that time. After a gap in the sedimentation history of several tens of thousands of years, ice‐wedge growth was re‐initiated around 50 ka BP by a short period of extremely cold winters and rapid sedimentation leading to ice‐wedge burial and characteristic ice‐soil wedges (‘polosatics’). This corresponds to the initial stage for the Late Weichselian Ice Complex, a peculiar cryolithogenic periglacial formation typical of the lowlands of northern Siberia. The Ice Complex ice wedges reflect cold winters and similar climatic conditions as around 200 ka BP. With a sharp rise in δ18O of 6‰ and δD of 40‰, the warming trend between Pleistocene and Holocene ice wedges is documented. Stable isotope data of recent ice wedges show that Big Lyakhovsky Island has never been as warm in winter as today. Copyright © 2002 John Wiley & Sons, Ltd.

New insights into the Weichselian environment and climate of the East Siberian Arctic, derived from fossil insects, plants, and mammals

“…It reached the lowest values at the end of the LGM (17-16 ka) and sharply rose to probably the highest values between 15 and 12 ka. Winter temperature during the interval from ca 50 to 12 ka was constantly much lower than present, as evidenced by continuous growth of thick ice wedges and the stable isotope composition of ice (Meyer et al, 2002). Even during pre-LGM time (Middle Weichselian), the reconstructed winter temperature was at least 7 1C lower than today (Meyer et al, in prep.).…”

“…Our recent work at the site was explicated with great detail in a series of reports (Siegert et al, 1999a, b;Sher et al, 2000Sher et al, , 2002b, presenting the geomorphology of the site, field descriptions of the section, lithology, permafrost features, sampling areas, and complete lists of various samples. These data, along with the results of age determinations, analysis of sedimentology, stable isotopes of ice wedges, the preliminary studies of organic fossils (pollen, plant macrofossils, testate amoebae, insects and mammals) were summarized in recent publications (Andreev et al, 2002;Meyer et al, 2002;Schirrmeister et al, 2002a, b;Siegert et al, 2002).…”

Lateglacial and Holocene isotopic and environmental history of northern coastal Alaska – Results from a buried ice-wedge system at Barrow

“…Therefore, samples taken from the top of ice wedges or from the bottom of the sediment column above ice wedges must be interpreted with caution for paleoclimatic purposes. The lateral influence between ice wedge and sediment has been demonstrated before (Meyer et al, 2002a). In the Barrow permafrost tunnel, the first two or three ice wedge samples adjacent to the lateral contacts (A, E, C 0 ) show a heavier isotopic composition than other samples of stable isotope cluster 1 (Fig.…”

“…Michel (1990) found that wedge ice may bear little relationship to that of the surrounding sediment due to the different geneses of wedge ice and texture ice. Isotopic and also ionic exchange is presumably driven by moisture migration of bound water (Meyer et al, 2002a), which tends to compensate potential differences either in ion concentration or temperature (Yershov, 1998). Therefore, these samples were discarded from paleoclimatic interpretation and the first accepted sample was at 30 cm distance from the lateral contacts.…”

PERMAFROST AND PERIGLACIAL FEATURES | Yedoma: Late Pleistocene Ice-Rich Syngenetic Permafrost of Beringia

“…Considering that ice wedges account for about 50% by volume of most Yedoma sequences, the total volumetric ground ice content likely ranges from 65 to 90%. Meyer et al, 2002;Vasil'chuk, 1992;Wetterich et al, 2011).…”