Gridded GEDI Vegetation Structure Metrics and Biomass Density at Multiple Resolutions

This dataset consists of near-global, analysis-ready, multi-resolution gridded vegetation structure metrics derived from NASA Global Ecosystem Dynamics Investigation (GEDI) Level 2 and 4A products associated with 25-m diameter lidar footprints. This dataset provides a comprehensive representation of near-global vegetation structure that is inclusive of the entire vertical profile, based solely on GEDI lidar, and validated with independent data. The GEDI sensor, mounted on the International Space Station (ISS), uses eight laser beams spaced by 60 m along-track and 600 m across-track on the Earth surface to measure ground elevation and vegetation structure between approximately 52 degrees North and South latitude. Between April 17th 2019 and March 16th 2023, GEDI acquired 11 and 7.7 billion quality waveforms suitable for measuring ground elevation and vegetation structure, respectively. This dataset provides GEDI shot metrics aggregated into raster grids at three spatial resolutions: 1 km, 6 km, and 12 km. In addition to many of the standard L2 and L4A shot metrics, several additional metrics have been derived which may be particularly useful for applications in carbon and water cycling processes in earth system models, as well as forest management, biodiversity modeling, and habitat assessment. Variables include canopy height, canopy cover, plant area index, foliage height diversity, and plant area volume density at 5 m strata. Eight statistics are included for each GEDI shot metric: mean, bootstrapped standard error of the mean, median, standard deviation, interquartile range, 95th percentile, Shannon's diversity index, and shot count. Quality shot filtering methodology that aligns with the GEDI L4B Gridded Aboveground Biomass Density, Version 2.1 was used. In comparison to the current GEDI L3 dataset, this dataset provides additional gridded metrics at multiple spatial resolutions and over several temporal periods (annual and the full mission duration). Files are provided in cloud optimized GeoTIFF format.

本数据集包含由美国国家航空航天局全球生态系统动力学调查（GEDI）第二级和第四级A产品生成的，针对近全球范围的、分析就绪的、多分辨率网格化植被结构指标。这些指标基于GEDI激光雷达，涵盖了整个垂直剖面，并经独立数据验证。GEDI传感器安装在国际空间站（ISS）上，沿地球表面使用八个间隔60米沿轨和600米横轨的激光束，以测量约52度北纬至南纬之间的地面高程和植被结构。在2019年4月17日至2023年3月16日期间，GEDI收集了11亿和77亿个可用于测量地面高程和植被结构的质量波形。本数据集提供了GEDI射击指标，这些指标已聚合为三种空间分辨率的栅格网格：1公里、6公里和12公里。除了许多标准L2和L4A射击指标外，还衍生出一些额外的指标，这些指标可能特别适用于地球系统模型中的碳循环和水循环过程的应用，以及森林管理、生物多样性建模和栖息地评估。变量包括冠层高度、冠层覆盖率、植物面积指数、叶高多样性以及5米层级的植物面积体积密度。每个GEDI射击指标包括八个统计数据：平均值、均值自举标准误差、中位数、标准差、四分位数范围、95百分位数、香农多样性指数和射击计数。采用了与GEDI L4B网格化地上生物量密度版本2.1相一致的质量射击过滤方法。与当前的GEDI L3数据集相比，本数据集提供了在多个空间分辨率和多个时间周期（年度和整个任务持续时间）上的额外网格化指标。文件以云优化GeoTIFF格式提供。