An international research team using data obtained by NASA – yes, that NASA – to boost our current understanding of our planet’s 3D structure has published a report containing some interesting findings about the structure of our tropical forests.
The data was collected through NASA’s Global Ecosystem Dynamics Investigation (GEDI) – a mission launched in 2018 to gain high-resolution measurements of the planet’s structure and discover how deforestation has impacted atmospheric CO2 concentrations.
Light Detection and Ranging (LiDAR) laser technology was attached to the International Space Station (ISS) as part of this mission. It beams a laser from the ISS onto the Earth thousands of times per day. Measurements are then recorded, with the time each laser takes to return, alongside the level of energy the satellite receives. The data generated from this process is used to form a 3D-map of the planet’s biomass.
GEDI data is expected to offer huge value for improving forest management practices, carbon cycle science, and weather predictions.
It is thanks to this technology that we now have access to the first global, high-resolution observations of the vertical structures of the world’s forests. Surprisingly, this work has shown the structure of our tropical forests is much simpler than previously believed and has more exposure to sunlight.
Hao Tang, Professor at the National University of Singapore and co-author of the paper, said key difference between GEDI and many other satellites is its ability to measure the 3D canopy structure.
“Conventional satellites, while providing valuable data on land cover and canopy greenness, often lack the detailed vertical information offered by GEDI,” Tang said.
“This vertical information is crucial for understanding ecosystem dynamics, carbon storage and biodiversity that cannot be easily seen from typical satellite images.”
With access to the 3D-maps, the research team concluded that trees in the vast majority of the world’s tropical forests have a peak in the number of leaves at a height of 15 metres rather than the top of the canopy, which was the previously accepted thinking.
As a result of these findings, the scientists were able to further conclude that any deviation from the ‘ideal’ conditions (such as lower soil quality, water shortages or higher temperatures) would lead to shorter and less-stratified (or ‘vertically layered’) forests with lower biomass.
Christopher Doughty, Professor at the University of Northern Arizona and co-author of the paper, said it was surprising to see the dominance of this structure type because it differs from what we had learned in the classic textbooks on the topic.
“These findings will not only help us understand how the millions of species that live in a rainforest canopy might acclimate to changing temperatures, but also how much carbon these forests hold and how good they are at fighting climate change,″ Doughty said.
Source – Engineering and Technology
