Orthoimagery and Shapefiles Documenting Pre- and Post-August 2019 Slope Disturbances, Teller Road Site, Seward Peninsula, Alaska, 2018-2019

This dataset was derived from UAS aerial photos and dGPS data collected at the Teller mile marker 47 site in 2018 and 2019 and used to support research quantifying the timing and rate of surface movements and analyze soil transport process in Arctic landscapes. In July 2018, a Phantom uncrewed aerial system (UAS) collected >6800 high resolution aerial photos of the lower portion of the Teller 47 watershed (see for raw photos; pending archive NGA281). During the UAS survey, 25 x 25 cm tile ground control points (GCPs) were laid out and secured with one rebar rod in the center. The four corners and rebar tops were surveyed with differential GPS, and these coordinates were used to construct and validate an orthomosaic of the site. These points were resurveyed in August 2019 and used to track annual movement. Changes in position between the two surveys are reported in (Lathrop et al. 2022; NGA254). Agisoft Metashape photogrammetry software was used to construct a georeferenced orthomosaic image (*.tif file) of a portion (0.68 km2) of the watershed with a final resolution of ~1 cm. Manual delineation of the perimeters of failures visible in the UAS imagery (*.tif files) was conducted to create shapefile polygons (two *.zip files). The failures were identified by the exposure of bare mineral soils, which were made visible by disruption of the overlying tundra vegetation. The shapefiles were then used to analyse the topographic distribution and sizes of the failures. In August 2019 an additional ~300 georeferenced UAS images of slope instability features were collected (data pending submission) and compared with the 2018 orthomosaic. Overview maps of the failure locations included as a *.pdf. The Next-Generation Ecosystem Experiments: Arctic (NGEE Arctic), was a research effort to reduce uncertainty in Earth System Models by developing a predictive understanding of carbon-rich Arctic ecosystems and feedbacks to climate. NGEE Arctic was supported by the Department of Energy's Office of Biological and Environmental Research. The NGEE Arctic project had two field research sites: 1) located within the Arctic polygonal tundra coastal region on the Barrow Environmental Observatory (BEO) and the North Slope near Utqiagvik (Barrow), Alaska and 2) multiple areas on the discontinuous permafrost region of the Seward Peninsula north of Nome, Alaska. Through observations, experiments, and synthesis with existing datasets, NGEE Arctic provided an enhanced knowledge base for multi-scale modeling and contributed to improved process representation at global pan-Arctic scales within the Department of Energy's Earth system Model (the Energy Exascale Earth System Model, or E3SM), and specifically within the E3SM Land Model component (ELM).

本数据集源自2018至2019年在特勒（Teller）47英里标记点采集的无人机系统（uncrewed aerial system, UAS）航拍照片与差分GPS（differential GPS, dGPS）数据，用于支撑北极地表运动时序与速率量化研究，并分析北极景观的土壤运移过程。2018年7月，一架精灵（Phantom）型无人机系统（uncrewed aerial system, UAS）采集了特勒47流域下游区域的6800余张高分辨率航拍照片，原始照片对应待归档存档编号NGA281。本次UAS航拍作业期间，布设了25×25厘米的瓦片式地面控制点（ground control points, GCPs），每个控制点中心均打入一根钢筋杆予以固定。使用差分GPS对控制点的四个角点及钢筋杆顶部进行坐标测量，以此构建并验证研究区域的正射影像镶嵌图。2019年8月对上述控制点进行了复测，用于追踪年度地表位移变化。两次测量间的位置变化已在Lathrop等人2022年的研究（存档编号NGA254）中予以报道。使用Agisoft Metashape摄影测量软件，对该流域0.68平方千米的区域构建了地理参考正射影像镶嵌图（*.tif文件），最终分辨率约为1厘米。对UAS影像（*.tif文件）中可见的热融滑塌区域进行手动勾勒，生成shapefile多边形矢量文件（包含两个*.zip压缩包）。此类滑塌由冻原植被覆盖层受扰动后裸露的矿质土壤所标识。随后利用该矢量文件分析热融滑塌的地形分布与规模特征。2019年8月，额外采集了约300张针对斜坡失稳特征的地理参考UAS影像（数据待提交），并与2018年的正射影像镶嵌图进行对比。热融滑塌位置的概览地图以*.pdf格式提供。下一代生态系统实验：北极（Next-Generation Ecosystem Experiments: Arctic, NGEE Arctic）是一项研究项目，旨在通过构建富碳北极生态系统的预测性认知及其对气候的反馈机制，降低地球系统模型的不确定性。该项目由美国能源部生物与环境研究办公室资助。NGEE Arctic设有两个野外研究站点：1）位于阿拉斯加州乌特恰维克（原巴罗）附近北坡的巴罗环境观测站（Barrow Environmental Observatory, BEO）的北极多边形冻原沿海区域；2）阿拉斯加州诺姆以北苏厄德半岛的不连续多年冻土区域内的多个点位。通过实地观测、控制实验与现有数据集综合分析，NGEE Arctic为多尺度建模提供了增强型知识库，并推动了美国能源部地球系统模型——能源极端尺度地球系统模型（Energy Exascale Earth System Model, E3SM），尤其是其陆面模型组件（E3SM陆面模型, ELM）在全球泛北极尺度下的过程表征精度提升。