Mapping and monitoring the Amazon from the airBy Carnegie Institution for Science
Project URL: cao.carnegiescience.edu
Greg Asner, a staff scientist at the Carnegie Institution for Science, quietly revolutionised forest monitoring when he packed a twin-propeller plane with some of the world’s most sophisticated mapping and laser technologies and took to the skies as the ‘Carnegie Airborne Observatory.’
For decades, ecologists have relied on two main tools to monitor forests – satellite images, which show simply whether an area has tree cover or not, and on-ground field surveys to identify individual trees in a specific, small area.
Asner’s plane, rigged with scanning and imaging equipment, was a game changer. The Carnegie Airborne Observatory includes Lidar (Light and Detection Ranging), an optical version of radar that bounces 500,000 laser pulses a second off the ground to produce a 3D image of the forest canopy – detailed enough to pick up a leaf even while flying at 280kph.
This system allowed Asner to draw the first large-scale map of biodiversity of the Amazon, the world’s biggest tropical forest, dubbed the ‘lungs of the world’ for its role in producing 20% of earth’s oxygen. Scraping data at a rate of 14 hectares a second, it reveals how many tree species the Amazon holds, how they are distributed, and shows the tree genus against maps of geology, precipitation and temperature.
The system also measures biomass, so Asner can make an accurate approximation of the amount of carbon stored in forests, helping Peru and others negotiate carbon-credit schemes with richer countries to fund conservation.
The system also maps and detects unregulated or illicit deforestation and forest degradation through CLASlite, a high-resolution satellite monitoring tool that uses algorithms to track changes in the forest as small as 10 square meters so scientists can find small-scale disturbances that have previously gone undetected.
And it is this drive, in the Amazon particularly, that could not be more urgent: Asner’s images showed that the average annual rate of forest loss has tripled since the financial collapse in 2008 sent the price of gold skyrocketing. Until his study, the huge tracts of devastation in the rainforest made by small-scale illegal mines, impossible to detect from the road, had gone largely unnoticed.
Image '36k foot view of the Amazon' courtesy of uıɐɾ ʞ ʇɐɯɐs
Last updated: 27th of May, 2014