Calibrating and Validating Australian and Global3-D Tree Mapping: Ground-Drone-Aircraft-Satellite LiDAR
Collecting Cal-Val Data for Satellite Products
In a recent collaborative effort, the University of Queensland (UQ) joined forces through the Joint Remote Sensing Research Program , Shaun Levick from CSIRO, Airborne Research Australia and NASA GEDI (Global Ecosystem Dynamics Investigation) to undertake a field campaign to enhance the calibration and validation of NASA's GEDI and NASA/ISRO’s NISAR satellite products. This initiative is a part of NASA’s Carbon Monitoring System, which supports the application of Earth Observation techniques for carbon monitoring and validation initiatives.
The fieldwork was conducted in remote areas near the towns of Mitchell and Injune, in central-south Queensland, where the team synchronously collected manual stem measurements and various LiDAR scanning contexts, including on-ground terrestrial laser scanning (TLS), high-spatial resolution drone scanning, and airborne LiDAR scanning (ALS). The data collected will aid the calibration and validation of satellite products used in Queensland and Australia for monitoring vegetation dynamics, including the Queenslabnd government’s vegetation mapping program, and Australian industry vegetation height products, such as Ozius Biome – in addition to (notably NASA’s GEDI sensor and NASA/ISRO’s NISAR mission). These will significantly contribute to the global scientific community’s efforts to quantify the carbon cycle.
The choice of the Injune site for this project was strategic, given its diverse representation of savanna and woodland ecosystems that are underrepresented in global datasets. Additionally, the site boasts a rich repository of historical data spanning nearly two decades, courtesy of its association with TERN Australia. This wealth of information provides a robust foundation for comparative analysis and trend assessment.
UQ’s representatives - Jason Dail (Doctoral candidate), Mark Wilson (Master’s student), and Dr Josh Rivory (postdoctoral research fellow) – helped collect TLS LiDAR scans and manual measurement of stem maps and Diameter at Breast Height (DBH). Despite the long days and unexpected challenges, notably, the day including 7 hours of driving and two flat tyres, the experience gained from this field campaign was invaluable. It enriched the scientific data gathered and provided significant hands-on learning opportunities for those involved.
Images provided by: Josh Rivory, John Armston, and Laura Duncanson.
