Yedoma Permafrost Landscapes as Past Archives, Present and Future Change Areas

The Research Topic „Yedoma permafrost landscapes as past archives, present and future change areas” was published in Frontiers in Earth Science in July 2022. Ice-rich permafrost deposits of late Pleistocene age (Yedoma Ice Complex) covered several million km² of the Arctic main land between the Taymyr Peninsula and the Yukon of Northwest Canada, from Central Yakutia to the Arctic shelves during the Last Glacial Maximum. Today about 1.9 million km² in Siberia, Alaska, and Northwest Canada are considered the modern remains of this Yedoma domain. Similar cold and dry climate conditions in different regions contributed to the prevalence of common deposit features such as relative fine-grained sediments, large syngenetic polygonal ice wedges, specific ground ice structures, significant amounts of buried well-preserved organic matter, and fossil remains of the mammoth megafauna and other tundra-steppe fauna and flora fossils. These once extensive periglacial landscapes, developed over tens of millennia in unglaciated regions where late Pleistocene syngenetic permafrost expanded, and degraded on a large scale during the latest Pleistocene and Holocene warming. This period of rapid thaw transformed these areas into lake-rich thermokarst (thaw) landscapes, while extensive continental shelf areas were flooded by the postglacial transgression of Arctic seas. Ice-rich Yedoma deposits are very vulnerable to climate warming, which leads to different landscape changes such as surface subsidence, thermokarst, thermoerosion, deepening of the active layer, as well as remobilization of buried freeze locked organic matter and its contribution to greenhouse gases fluxes.

Papers of this Yedoma Research Topic represent a broad view on current know-ledge in permafrost research with respect to Yedoma permafrost landscapes. Since about 150 years research was undertaken to highlight the formation and development of Yedoma deposits based on cryolithological and paleo-environmental records, and to deduce present Yedoma landscape dynamics and their future response to climate change. Understanding the formation and storage of organic matter preserved in Yedoma deposits requires paleoenvironmental research to estimate the extrinsic (climate) and intrinsic (periglacial processes) controls on permafrost aggradation and degradation.

This Research Topic brings together 27 scientific articles at 67 study sites in Russia and Alaska, involving 148 authors from 68 institutes in 11 countries. This paper collection is the final activity of the International Permafrost Association (IPA) action group "The Yedoma Region: A Synthesis of Circum-Arctic Distribution and Thickness“.