Lidar Scans of the White River near Worthington, Indiana, U.S.A.: Supporting data for Martin et al. (2024)

Supporting data for the manuscript "Four years of meander-bend evolution captured by drone-based lidar reveals lack of width maintenance on the White River, Indiana, USA" by Harrison K Martin, Douglas A Edmonds, and Quinn W Lewis. As of June 2024, the manuscript has been published in the Journal of Geophysical Research: Earth Surface and is available here: https://doi.org/10.1029/2023JF007574. You can find additional details in the Supplemental Information for that paper.

Also of interest may be another recently published manuscript (in Earth Surface Processes and Landforms) on a pair of failed dams from central Michigan where we quantified topographic change using lidar change detection. On that study, we compared an airborne pre-flood survey to three post-flood drone-based lidar surveys we collected. The methods employed were not identical to this study (namely, there we used a point cloud to point cloud differencing method rather than the differences of DEMs used here), but there could be some helpful information in that manuscript's Supporting Info. It's available here: https://doi.org/10.1002/esp.5855.

In this repository you will find 22 bare-earth Digital Elevation Models (DEMs) of a single river bend on the meandering White River near Worthington, IN. The scans were collected over a period of ~4.5 years between April 2018 and November 2022 -- not coincidentally, nearly the same span of time as my PhD. Each DEM attempts to present the bare earth as if the vegetation were not present; the algorithms and trimming do a better job on tall, forested canopies (such as the northeastern-most part of the point bar) than on short, dense, shrubby grasses (such as certain parts of the cutbank or where crops were grown). The vegetation noise and artifacts will be the greatest in the summer months and the least in the winter. The point bar surface was always well-resolved. The actual river/water surface itself was masked out manually for each of the 22 scans, with null values defined for these and other no-data areas. The filename of each scan describes the date of collection. The cell size for each raster is 25 cm and was created by exporting a triangular lattice constructed from a ground-classified point cloud with a maximum length of 10 meters. Because of this, areas with very low point density (such as the outer boundaries of each scan, outside of the areas where we wanted to measure geomorphic changes) appear to be made of large triangles, and should not be trusted. The CRS for each is NAD83 / UTM zone 16N [https://epsg.io/26916].

Please do not hesitate to reach out with any questions, requests, etc! I'm pretty responsive by email ([e-mail]) and website form (https://harrison.studies.rocks). If you have any questions about the methods, setting up your own drone-based lidar program, or are struggling with some of the arcane software and quirks of this sort of workflow... there is a chance that I've struggled through it before and am happy to share whatever I have learned!

Thanks for stopping by!

Acknowledgements:

A big thanks is owed to Steve Scott of Indiana University, our stalwart drone pilot without whom none of this would have been possible. HKM was supported by National Aeronautics and Space Administration (NASA) Future Investigators in NASA Earth and Space Science and Technology (FINESST) grant 80NSSC21K1598 and a California Institute of Technology Geological and Planetary Sciences Geology Option Postdoctoral position. DAE was supported by National Sciences Foundation grant EAR-2321056. QWL was supported by a University of Waterloo New Faculty Starter Grant. All authors were supported by the Environmental Resilience Institute, funded by Indiana University’s Prepared for Environmental Change Grand Challenge initiative.

UPDATES: - 2024-04-29: Added Supporting Tables S1-S6.- 2024-05-04: Updated some column headers in Supporting Tables S1-S6.- 2024-05-08: Made public, updated the first paragraph (including changing manuscript status to accepted), and added contact information for further inquiries.- 2024-06-20: Added DOI link to published manuscript in JGR:ES. Added a reference to our ESPL paper for those interested in more methodology details. Expanded the description of how the data were collected and processed, as well as my contact information, to make the repository a bit more user-friendly.

本数据集为Harrison K Martin、Douglas A Edmonds与Quinn W Lewis合著的论文《无人机载激光雷达（drone-based lidar）捕捉美国印第安纳州白河四年曲流演化过程揭示河道宽度维持缺失》的支撑数据。截至2024年6月，该论文已发表于《地球物理研究杂志：地球表面》（*Journal of Geophysical Research: Earth Surface*），可通过以下链接获取：https://doi.org/10.1029/2023JF007574。更多细节可查阅该论文的补充信息（Supplemental Information）。

此外，您也可参考我们在《地表过程与地貌》（*Earth Surface Processes and Landforms*）发表的另一项近期研究：针对密歇根州中部两处溃坝的案例，我们通过激光雷达变化检测（lidar change detection）量化了地形变化。该研究中，我们将航空拍摄的洪水前勘测数据与我们获取的三次洪水后无人机载激光雷达勘测数据进行对比。本研究采用的方法与该研究不完全一致（具体而言，该研究使用点云对点云差分方法，而非本研究使用的数字高程模型（DEM，Digital Elevation Model）差分方法），但该论文的补充信息中或许包含可供参考的内容，链接为：https://doi.org/10.1002/esp.5855。

本仓库包含22份针对印第安纳州沃辛顿附近蜿蜒白河单个河弯的裸地数字高程模型（DEMs，Digital Elevation Models）。数据采集时间跨度约4.5年，介于2018年4月至2022年11月之间——巧合的是，这一周期几乎与我的博士攻读时长一致。每份DEM均旨在呈现去除植被后的裸地表层：算法与裁剪处理对高大森林冠层（如边滩（point bar）最东北部区域）的去除效果优于低矮茂密的灌草丛（如凹岸（cutbank）部分区域或农作物种植区）。植被噪声与伪影在夏季最为显著，冬季则最弱。边滩表面始终具备良好的分辨率。针对22份扫描数据中的每一份，我们均手动掩膜了实际河道/水面区域，并为该区域及其他无数据区域赋值为空值。每份扫描数据的文件名均标注了采集日期。每份栅格数据的像元尺寸为25厘米，通过导出由地面分类点云构建的三角格网生成，该格网的最大边长为10米。因此，点密度极低的区域（如每份扫描数据的外边界，即我们计划测量地貌变化区域之外的部分）会呈现为大三角格网形态，此类区域的数据不可靠。所有数据的坐标参考系统（CRS，Coordinate Reference System）均为NAD83 / UTM 16N带，详情可查阅：https://epsg.io/26916。

如有任何疑问、需求或其他事宜，欢迎随时联系！我通常会及时回复邮件（[e-mail]）或通过网站表单（https://harrison.studies.rocks）进行回复。若您对研究方法、搭建自有无人机载激光雷达项目存在疑问，或是在这类工作流程中遇到晦涩的软件操作与异常问题——我大概率曾遇到过类似难题，乐意分享我积累的相关经验。

感谢您访问本仓库！

致谢：
衷心感谢印第安纳大学的Steve Scott——我们可靠的无人机操作员，若无他的协助本项目无法完成。HKM受美国国家航空航天局（NASA）NASA地球与空间科学与技术未来研究者计划（FINESST）项目编号80NSSC21K1598以及加州理工学院地质与行星科学系地质学方向博士后职位资助。DAE受美国国家科学基金会（National Science Foundation）项目编号EAR-2321056资助。QWL受滑铁卢大学新教师启动基金资助。所有作者均受环境韧性研究所资助，该研究所由印第安纳大学“应对环境变化”重大挑战项目设立。

更新记录：
- 2024-04-29：新增补充表S1-S6。
- 2024-05-04：更新补充表S1-S6的部分列标题。
- 2024-05-08：将仓库设为公开状态，更新首段内容（包括将论文状态更新为已发表），并补充了进一步咨询的联系方式。
- 2024-06-20：添加了发表于《地球物理研究杂志：地球表面》的论文的DOI链接；为需要更多方法细节的读者补充了我们发表于《地表过程与地貌》的论文参考文献；扩充了数据采集与处理流程的描述，以及我的联系方式，以提升本仓库的易用性。