Laser technology called lidar is helping archaeologists complete years of fieldwork sometimes in the span of a single afternoon
Archaeology is facing a time crunch. Thousands of years of human history risk imminent erasure, from tiny hamlets to entire cities - temples, walls and roads under grave threat of destruction. Urban sprawl and industrial agriculture are but two culprits, smothering ancient settlements beneath car parks and cattle pastures. International conflict and climate change are also damaging vulnerable sites, with warfare and water shortages destroying pockets of history across the world.
The endless excavations of yesteryear are no longer the best solution. Big digs aren’t the big idea they once were: mapping the human archaeological record is now moving upward, into the sky.
Lidar – short for light detection and ranging – has emerged as one of the most widely used technologies for rapid archaeological documentation. Lidar works by sending pulses of light out from a transmitter often mounted to the skid of a helicopter, then recording how long it takes for those pulses to return to a sensor. A virtual 3D map can be generated from a single large-scale survey in less than a day. Archaeological sites that would require years and years of fieldwork to excavate can now be mapped in a single afternoon, their every surface feature captured down to millimeter-scale resolution.