ABoVE: LVIS L3 Gridded Vegetation Structure across North America, 2017 and 2019

This dataset provides Level 3 (L3) footprint-level gridded metrics and attributes collected from NASA's Land, Vegetation, and Ice Sensor (LVIS)-Facility instrument for each flightline from 2017 and 2019. In 2017, the LVIS-Facility instrument was flown at a nominal flight altitude of 28,000 ft onboard a Dynamic Aviation Super King Air B200T. In 2019, the LVIS-Facility and LVIS-Classic instruments were flown at a nominal flight altitude of 41,000 feet onboard the NASA Gulfstream V. LVIS data are collected as waveforms over footprints of ~10-m diameter. The L3 data include grids of canopy relative height (RH), complexity, canopy cover (CC), ground elevation, and the number of LVIS footprints available to produce a pixel's estimate.. These 30-m resolution grids describe the vertical column of the vegetation canopy in detail with relative canopy height metrics and are enriched with an additional set of canopy cover estimates at a variety of height thresholds. The LVIS-Facility instrument 2017 and 2019 acquisitions span Arctic, boreal, temperate, and sub-tropical landscapes in support of a variety of Arctic-Boreal Vulnerability Experiment (ABoVE)- and Global Ecosystem Dynamics Investigation (GEDI)-related science. In the ABoVE study domain of arctic and boreal Alaska and Western Canada, some of these acquisitions coincide spatially with legacy small-footprint airborne lidar. Data are included for the ABoVE domain and also for the continental U.S. and central America in support of GEDI calibration and validation. Data files are provided in GeoTIFF format and one geopackage file shows flightlines.

本数据集提供了3级（Level 3, L3）足迹级栅格指标与属性信息，数据采集自美国国家航空航天局（National Aeronautics and Space Administration, NASA）的陆地、植被与冰传感器（Land, Vegetation, and Ice Sensor, LVIS）-Facility仪器，涵盖2017年与2019年的每条飞行航线。2017年，LVIS-Facility仪器搭载于Dynamic Aviation超级空中国王B200T飞机，标称飞行高度为28000英尺。2019年，LVIS-Facility与LVIS-Classic两款仪器搭载于NASA湾流V（Gulfstream V）飞机，标称飞行高度为41000英尺。LVIS数据以波形形式采集，对应直径约10米的足迹区域。本次提供的L3级数据包含冠层相对高度（RH）、复杂度、冠层覆盖度（CC）、地面高程，以及用于生成像元估算值的LVIS足迹数量等栅格图层。这些30米分辨率的栅格详细刻画了植被冠层的垂直结构，包含相对冠层高度指标，并补充了多组不同高度阈值下的冠层覆盖度估算结果。2017与2019年的LVIS-Facility仪器观测任务覆盖北极、寒带、温带与亚热带景观，服务于北极-寒带脆弱性实验（Arctic-Boreal Vulnerability Experiment, ABoVE）以及全球生态系统动力学调查（Global Ecosystem Dynamics Investigation, GEDI）相关的多项科学研究。在阿拉斯加北极-寒带区域与加拿大西部的ABoVE研究域内，部分观测航线与遗留的小足迹机载激光雷达数据空间重合。本数据集除覆盖ABoVE研究域外，还包含美国本土与中美洲区域的数据，用于支撑GEDI的校准与验证工作。数据集采用GeoTIFF格式存储，另有一个地理数据包（geopackage）文件用于展示飞行航线。