NASA will soon turn a laser-based device toward Earth in an effort to map its forest in 3D. This endeavor, which will originate the International Space Station and goes by the name GEDI, is all part of the agency's plan to determine the amount of carbon our planet's forests contain.
peering into the forest canopy with lasers
"One of the most poorly quantified components of the carbon cycle is the net balance between forest disturbance and regrowth," said Ralph Dubayah, GEDI principal investigator at the University of Maryland, in a statement yesterday. "GEDI will help scientists fill in this missing piece by revealing the vertical structure of the forest, which is information we really can't get with sufficient accuracy any other way."
GEDI, which is an acronym for "Global Ecosystem Dynamics Investigation," will make use of lidar technology to map Earth's forests. This type of technology refers to lasers and light and, in this context, its use will consist of sending out laser pulses to the Earth's surface from three separate lasers. Once these pulses reach Earth, they will bounce back to GEDI, allowing it to measure distance — and ultimately the planet's topography — based on the amount of time the process takes. According to NASA, GEDI will send out 16 billion pulses in a year, and the subsequent measurements will be precise enough to determine a tree canopy's height with an accuracy of about three feet.
"information we really can't get with sufficient accuracy any other way."
"Lidar has the unique ability to peer into the tree canopy to precisely measure the height and internal structure of the forest at the fine scale required to estimate their carbon content," said deputy principal investigator for GEDI Bryan Blair.
NASA thinks that the project represents a particularly powerful means of measuring carbon on a global scale. The researchers hope to use GEDI's measurements to gather information about land use and habitat diversity. They also have plans to compare carbon measurements with historical records. GEDI is currently in development, and it's expected to launch in 2018.