Description: Datasets that provide high-resolution palaeoenvironmental information during the last glacial maximum in Chukotka, Arctic Siberia are limited. This data compilation comprises multiproxy data extracted from sediment core EN18218 obtained from Arctic glacial lake Rauchuagytgyn (67.7922°N, 168.7312°E) by piston coring during the Chukotka 2018 expedition. The dataset covers the late Pleistocene and Holocene (ca. 29 cal. ka BP). Observations within this dataset include 14C radiocarbon dates, hydrochemistry observations, sedimentological observations (water content, bulk density, grain-size, sediment color, biogeochemistry (Total sulphur (TS), Total carbon (TC), Total organic carbon (TOC), Total inorganic carbon (TIC)), X-ray fluorescence (XRF) based sediment-geochemistry and magnetic susceptibility measurements. Radiocarbon dating was performed with accelerator mass spectrometry (AMS) using the Mini Carbon Dating System (MICADAS) at AWI Bremerhaven, Germany. Water content and bulk density were measured according to the volumetric methods of Avnimelech et al, (2001). Sediment grain-size was measured using a Malvern Mastersizer 3000 laser diffraction particle analyser. Biogeochemical parameters were obtained using a Vario SoliTOC cube elemental analyser "Elementar Corp., Germany) and Eltra Carbon and Sulfur determinator (Eltra GmbH, Germany). XRF and color scanning was performed using an Avaatech core-scanner and line-scanner attachment. Magnetic susceptibility measurements were performed with a Bartington MS2E spot reading sensor. A full description of methodological procedures used within this study is provided in the publication (Vyse et al., in review).

Description: Datasets that provide palaeoenvironmental information extending beyond marine isotope stage 3 (MIS3) in Chukotka, far east Russia are limited. This data compilation comprises multiproxy sediment-geochemical, sedimentological and preliminary biological data from sediment core EN18208 obtained from lake Ilirney (67°21'N, 168°19'E), Chukotka by piston coring during the Chukotka 2018 expedition. Observations within this dataset include radiocarbon and optically stimulated luminescence (OSL) dates, X-ray fluorescence (XRF) based sediment-geochemistry, sedimentological observations (water content, bulk density, grain-size, biogeochemistry (Total carbon (TC), Total nitrogen (TN), Total organic carbon (TOC)), mineralogy) and preliminary biological data (Diatom percentages from smear slides and diatom benthic/planktonic ratios from diatom slides). The provided data compilation provides observations permitting the palaeoenvironmental reconstruction of lake Ilirney since 53.4 ka BP during the late Pleistocene.