Circum-Arctic Map of the Yedoma Permafrost Domain

Abstract

Ice-rich permafrost in the circum-Arctic and sub-Arctic (hereafter pan-Arctic), such as late Pleistocene Yedoma, are especially prone to degradation due to climate change or human activity. When Yedoma deposits thaw, large amounts of frozen organic matter and biogeochemically relevant elements return into current biogeochemical cycles. This mobilization of elements has local and global implications: increased thaw in thermokarst or thermal erosion settings enhances greenhouse gas fluxes from permafrost regions. In addition, this ice-rich ground is of special concern for infrastructure stability as the terrain surface settles along with thawing. Finally, understanding the distribution of the Yedoma domain area provides a window into the Pleistocene past and allows reconstruction of Ice Age environmental conditions and past mammoth-steppe landscapes. Therefore, a detailed assessment of the current pan-Arctic Yedoma coverage is of importance to estimate its potential contribution to permafrost-climate feedbacks, assess infrastructure vulnerabilities, and understand past environmental and permafrost dynamics. Building on previous mapping efforts, the objective of this paper is to compile the first digital pan-Arctic Yedoma map and spatial database of Yedoma coverage. Therefore, we 1) synthesized, analyzed, and digitized geological and stratigraphical maps allowing identification of Yedoma occurrence at all available scales, and 2) compiled field data and expert knowledge for creating Yedoma map confidence classes. We used GIS-techniques to vectorize maps and harmonize site information based on expert knowledge. We included a range of attributes for Yedoma areas based on lithological and stratigraphic information from the source maps and assigned three different confidence levels of the presence of Yedoma (confirmed, likely, or uncertain). Using a spatial buffer of 20 km around mapped Yedoma occurrences, we derived an extent of the Yedoma domain. Our result is a vector-based map of the current pan-Arctic Yedoma domain that covers approximately 2,587,000 km2, whereas Yedoma deposits are found within 480,000 km2 of this region. We estimate that 35% of the total Yedoma area today is located in the tundra zone, and 65% in the taiga zone. With this Yedoma mapping, we outlined the substantial spatial extent of late Pleistocene Yedoma deposits and created a unique pan-Arctic dataset including confidence estimates.

Yedoma Cryostratigraphy of Recently Excavated Sections of the CRREL Permafrost Tunnel Near Fairbanks, Alaska

“…Yedoma deposits contain large ice wedges that can reach up to 10 m in width and more than 40 m in vertical extent (Tomirdiaro 1980;Zhestkova et al, 1982;Sher, 1997;Romanovskii et al, 2004;Kanevskiy et al, 2011;Murton, 2013;Schirrmeister et al, 2013;Schirrmeister et al, 2020). Yedoma remnants are abundant in various parts of Siberia, Canada, and Alaska (Kanevskiy et al, 2011;Schirrmeister et al, 2013;Strauss et al, 2017;Strauss et al, 2021;and citations therein).…”

“…Yedoma in Siberia and North America occurs in an area of ∼450,000 km 2 , including ∼90,000 km 2 in Alaska (Strauss et al, 2021), and contains up to 130 gigatons of organic carbon (Strauss et al, 2017). Yedoma is vulnerable to climate change and disturbance because of its high ice content and silty composition.…”

Organic matter characteristics of a rapidly eroding permafrost cliff in NE Siberia (Lena Delta, Laptev Sea region)

“…Climate warming puts permafrost, especially ice-rich permafrost, in the terrestrial Arctic at risk of thawing (e.g. Strauss et al, 2021b). Permafrost, by definition, is ground that stays below 0 • C for 2 or more consecutive years.…”

“…Almost twice as much carbon is stored in the permafrost region than what is currently contained in the atmosphere (Hugelius et al, 2014;Mishra et al, 2021), making permafrost carbon dynamics a globally relevant issue (Grosse et al, 2011;Schuur et al, 2008;Strauss et al, 2021a;Turetsky et al, 2020). Total estimated soil organic carbon (SOC) storage for the permafrost region is ∼ 1100-1600 Gt, of which 181 ± 54 Gt is attributed to deep permafrost (below 3 m depth) of the Yedoma region (Hugelius et al, 2014;Strauss et al, 2021bStrauss et al, , 2013.…”

Pan-Arctic soil element availability estimations

“…1460 -1600 Pg carbon is stored in the permafrost region (Strauss et al, 2021a), and approximately one third of this is in ice rich Yedoma deposits, exceeding 3m depth (Fuchs et al, 2018;Strauss et al, 2017). The Yedoma deposits formed in unglaciated areas of the northern hemisphere during the glacial period, when melt water from glacial areas and eolian processes transported fine sediment to the unglaciated lowlands (Schuur et al, 2013;Strauss et al, 2021b;Strauss et al, 2013). Yedoma deposits are characterized by high carbon and water content.…”