Database of Ice-Rich Yedoma Permafrost Version 2 (IRYP v2)

Ice-rich permafrost in the circum-Arctic and sub-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. 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.Hence, here we synthesize data on the circum-Arctic and sub-Arctic distribution and thickness of Yedoma for compiling a preliminary circum-polar Yedoma map.To harmonize the different datasets and to avoid merging artifacts, we applied map edge cleaning while merging data from different database layers. For the digitalization and spatial integration, we used Adobe Photoshop CS6 (Version: 13.0 x64), Adobe Illustrator CS6 (Version 16.0.3 x64), Avenza MAPublisher 9.5.4 (Illustrator Plug-In) and ESRI ArcGIS 10.6.1 for Desktop (Advanced License). Generally, we followed workflow of figure 2 of the related publication (IRYP Version 2, Strauss et al 2021, https://doi.org/10.3389/feart.2021.758360).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.

环北极与亚北极地区的富冰多年冻土，诸如晚更新世耶多玛（Yedoma）沉积，因气候变化与人类活动极易发生退化。当耶多玛沉积物解冻时，大量冻结有机质与生物地球化学相关元素会重新进入当前的生物地球化学循环。在既往制图工作的基础上，本文旨在编制首份泛北极耶多玛数字地图及耶多玛覆盖范围空间数据库。具体工作包括：1）合成、分析并数字化了各类比例尺的地质与地层图，从而可在所有可用比例尺下识别耶多玛的分布点位；2）整合野外实测数据与专家知识，以划分耶多玛地图的置信等级。我们采用地理信息系统（Geographic Information System, GIS）技术对地图进行矢量化处理，并基于专家知识统一协调站点信息。据此，本文整合了环北极与亚北极地区耶多玛的分布与厚度数据，以编制首份环极地耶多玛初步地图。为统一协调不同数据集并避免合并伪影，我们在合并不同数据库图层的数据时，执行了地图边缘清理操作。数字化与空间整合工作所使用的工具包括：Adobe Photoshop CS6（版本：13.0 x64）、Adobe Illustrator CS6（版本16.0.3 x64）、Avenza MAPublisher 9.5.4（Illustrator插件）以及ESRI ArcGIS 10.6.1 Desktop高级许可版。整体而言，我们遵循了相关出版物（IRYP版本2，Strauss等，2021，https://doi.org/10.3389/feart.2021.758360）中图2所示的工作流程。我们基于源地图的岩性与地层信息，为耶多玛区域设置了多组属性，并将耶多玛存在的置信等级划分为三类：已确认、可能与不确定。我们围绕已制图的耶多玛分布点位设置了20 km的空间缓冲区，以此推导出耶多玛域的分布范围。本次研究的成果为一幅基于矢量的当前泛北极耶多玛域地图，总覆盖面积约258.7万平方千米，其中48.0万平方千米范围内分布有耶多玛沉积物。我们估算，当前耶多玛总面积的35%分布于苔原带，65%分布于泰加林带。通过本次耶多玛制图工作，我们明确了晚更新世耶多玛沉积物的广阔空间分布范围，并创建了包含置信度评估的独特泛北极数据集。