Radiocarbon age, stable isotope composition of Holocene ice wedges and mean January air temperatures in the Kolyma Lowland region

Ice wedges visible in natural alas and floodplain exposures have been studied in 1983-2018 years in the Kolyma Lowland region. Most ice wedges have been found within alases dated between 11 and 4.2 cal kyr BP, corresponding to the Greenlandian and Northgrippian stages of the Holocene. The greatest intensity of ice wedge growth occurred during 10.5-6 cal kyr BP. A decrease in their growth was mainly caused by alas draining and reduced sedimentation. In the last 4-4.5 cal kyr BP (Meghalayan stage of the Holocene), ice wedges continued to grow in old alases, sometimes as a younger generation, as well as within young alases and floodplains of the Kolyma River and its tributaries. Stable oxygen isotope values of ice-wedge ice have been successfully used as a basis for winter paleotemperature reconstructions. Obtained paleotemperature information shows that during the Holocene, mean January air temperature did not fluctuate significantly in the Kolyma Lowland region, with a slight decrease during the Meghalayan stage.