Isoscapes of Holocene relict glaciers in the Russian Arctic as a basis for analyzing the spatial distribution of isotopic composition of winter precipitation and air temperatures

The subject of the research is a review of isoscape maps in various fields of Earth science over the past 10-12 years, with a particular focus on the analysis of isoscape values of δ18O and δ2H in atmospheric precipitation, surface and groundwater, and glacial ice, highlighting the approaches to their construction and practical applications. Aspects of constructing isoscape values of δ18O in dated syn-genetic reworked ice from the Siberian sector of the Russian cryolithozone are considered as a basis for analyzing air mass circulation in the Late Pleistocene and Holocene and for creating large-scale maps of paleo-isotherms of mean January and mean winter air temperatures. It is shown that the increase in the volume of isotopic data from reworked ice and their reliable age correlation allows for the creation of more detailed isoscape and paleo-isotherm maps for designated periods of the Late Pleistocene. Aspects of constructing isoscape values of δ18O in Holocene and modern reworked ice from two Arctic regions (northern West Siberia and Chukotka), for which significant isotopic data have been obtained over the past 25 years, are examined. The age correlation of the isotopic data was performed based on dating of host sediment and microorganisms from the reworked ice. It is demonstrated that for the extensive territory of the Siberian cryolithozone, the spatial distribution of δ18O values in reworked ice during the Late Pleistocene (30-12 thousand years ago) is similar to the distribution of δ18O values in modern veins, indicating a close nature of air mass transfer and the conditions for the formation of isotopic composition of winter precipitation in the subarctic zone of Siberia during the Late Pleistocene as well as more recent periods. Regional maps of isoscape values of δ18O in modern and Holocene reworked ice in West Siberia and Chukotka show lower δ18O values (by 1-3 ‰) in Holocene veins compared to modern ones, as well as a tendency for decreasing values in more continental areas of the territories, reflecting the continental isotopic effect in precipitation – a decrease in δ18O values as one moves away from the precipitation formation source.