Airborne LiDAR technology creates three dimensional images of a landscape, including everything from the ground surface to the uppermost object of the area, whether that is the top of a tree or a bird. All the vegetation cloaking the ground is painstakingly filtered from the LiDAR images using computer software. Image courtesy Chris Fisher Finding tools of conservation in the cloudsImage of

Finding tools of conservation in the clouds

As appearing in National Geographic

Powerful enough to peer through the thick vegetation of jungle canopies, LiDAR technology is helping explorers find hidden ancient settlements.

The field of archaeology conjures images of scientists, kneeling on the ground delicately scraping the earth for traces of the past. For the “lost city” of Ciudad Blanca in the valley of Mosquitia, Honduras, archaeology begins in the sky.

Archaeologist Chris Fisher, of Colorado State University, is an expert in the jungle-canopy-penetrating imagery known as LiDAR, or light detecting and ranging. A few years ago, Fisher used aerial imaging tool LiDAR to reveal that a pre-Columbian site in central Mexico was far larger than explorers on the ground had detected.

 

  During the ground verification efforts, or ground-truthing, aerial LiDAR images captured from above jungle canopies are brought to the ground using handheld computers paired with sub-meter GPS systems.  Photograph by Dave Yoder/National Geographic


During the ground verification efforts, or ground-truthing, aerial LiDAR images captured from above jungle canopies are brought to the ground using handheld computers paired with sub-meter GPS systems.
Photograph by Dave Yoder/National Geographic.

 

In 2012, Fisher made another breakthrough discovery, by analyzing LiDAR images that showed traces of human modification in one of the largest remaining areas of unexplored rainforest in Central America. LiDAR produces landscape details as precise as water control features like reservoirs, canals, and agricultural terraces, providing a digital map to unlocking the secrets of a lost civilization.

In February 2015, Fisher and his Honduran-American archaeological team became ancient mythbusters when Fisher downloaded the LiDAR maps using a Trimble GPS unit to call out directions as they machete-wielded their way through the thick vegetation of an area connected to rumors of the lost city, Ciudad Blanca, or “City of the Monkey God.” Contrary to the legend of a single lost city, archaeologists believe multiple lie within the remote valley of Mosquitia. The lost cities discovered on the initial descent into the ruins are simply known as T1 and T3, Target One and Target Three.

By taking archaeology airborne, LiDAR makes it possible to uncover clues in areas where little to no archaeological data currently exists due to heavy vegetation or rugged topography. On the second day of exploration in 2015, Fisher and the team found a preserved record of a vanished civilization in a stone cache containing 200 sculptures. Fisher and team began excavation on the stone cache earlier this year in January.

 

  Airborne LiDAR technology creates three dimensional images of a landscape, including everything from the ground surface to the uppermost object of the area, whether that is the top of a tree or a bird. All the vegetation cloaking the ground is painstakingly filtered from the LiDAR images using computer software.  Image courtesy Chris Fisher

Airborne LiDAR technology creates three dimensional images of a landscape, including everything from the ground surface to the uppermost object of the area, whether that is the top of a tree or a bird. All the vegetation cloaking the ground is painstakingly filtered from the LiDAR images using computer software.
Image courtesy Chris Fisher

 

“We’re very excited to bring to life this lost culture,” Fisher said, noting that the research “will significantly change our understanding of this critical archaeological region.”

The possibility of bringing life to the culture of a lost civilization is threatened only by time and deforestation. The pristine Mosquitia rainforest and culture of its past inhabitants is dangerously close to being destroyed by deforestation caused by Central America’s booming beef-production industry. In the two years since three areas were documented with LiDAR, illegal clearing and deforestation has approached within 12 miles of one valley, and decimated the floor of a second. Continued discovery depends on explorers like Fisher introducing innovative tools like LiDAR to enhance ecological strategies and preservation.

“Through this amazing project we were able to use LiDAR as a tool that resulted in the discovery of a lost world,” Fisher said. “We hope to continue this work in the future to more fully unravel this puzzle through archaeological excavation and ecological investigation.”