Ground Truth:
Why Satellites Aren’t Enough
Behind The Tech: The Synergy between NatureOS & Satellite Data
But… is this enough?
As with all technology, there are limitations that have yet to be overcome. Carbon stocks often get inaccurately represented by satellite data due to tree canopy cover. As leaves and branches form dense canopy cover more than a hundred metres off the forest floor, lasers used in LiDAR capturing are unable to uncover vegetation and terrain hidden underneath.
Satellite data alone also cannot account for local variations in factors like tree species composition, wood density, and site conditions, which can significantly influence carbon stocks.
With such huge gaps in knowledge from relying on remote sensing technology alone, the need for a more reliable method for measurement is evident.
Ground Truth: The Critical Piece
Ground truth serves as the anchor that grounds remote sensing data in reality. By directly collecting measurements and observations on-site, scientists can validate and cross-reference new data with satellite and LiDAR-derived data, ensuring accuracy and reliability. This includes collecting field measurements of tree diameter, biomass, soil carbon content, plant species, water chemistry and more. With boots on the ground, we use ground truth to verify and eliminate our biases.
While it is not convenient at all to measure ground truth, the importance of acquiring accurate carbon estimations for land projects and unlocking nature investments cannot be understated. The critical problem here is that ground truth collection is manual: a laboursome task that involves many days of field measurements, sampling and plot-based monitoring.
An Uphill Task
Ground truth collection for forest carbon biomass typically hinges on manual methodologies, a process steeped in traditional techniques, especially in Asia:
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This approach entails employing tools like measuring tape and clinometers to document parameters such as height and diameter at breast height (DBH), standardised at 1.30 meters
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These raw field measurements serve as the bedrock for subsequent calculations employing allometric models, facilitating biomass estimation






