Climate change is not only an existential threat to our livelihoods and that of countless other species with whom we share the world, but also threatens the relics of ancient cultures. Sea level rise, extreme weather events, wildfires, and desertification are some of the threats that could destroy both historic and contemporary sites, such as archeological sites, coastal cities, rainforests, and coral reefs. With this potential catastrophic future in mind, two daring scientists have hatched up an ambitious plan, not to avert this damage, but rather to conserve the memory of the world as we know it today for future generations by archiving it.
Archaeologist Chris Fisher and geographer Steve Leisz, both scientists at Colorado State University, are worried about the legacy they can leave to future generations. They think that we're on a collision course with accelerated climate change and unless we have a record of the places that will be swept by the coming tempest, it will be as if they were never there.
This is why the two have started Earth Archive, a project whose ultimate goal is to create a 3D map of the entire world's surface. But, how would that even be possible?
The key lies in a mapping technology known as light detection and ranging, or LiDAR.
LiDAR or 3D laser scanning was developed in the early 1960s for submarine detection from the air via aircraft. It works by generating a laser pulse train that is so fine that it can travel through the gaps of dense vegetation. By calculating the time it takes for the laser pulse to reflect back to its source, researchers can determine the elevation of the ground and create a 3D representation of any structure.
The technology is routinely used today to survey topography. While not too long ago it would take years to map an area, it now takes merely days.
Previously, LiDAR was used to reveal a huge medieval city in the Cambodian jungle, long-lost Roman roads, and over 60,000 breathtaking Mayan structures hidden away in the deep Amazon. NASA is also using LiDAR to map the Amazon rainforest's canopy cover in order to estimate the effects of drought and other climate change effects.
Earth Archive would focus on the planet's landmass, which covers roughly 29% of the surface. The most vulnerable places, such as the Amazon rainforest and coastal regions, would be prioritized.
There is real value in such an endeavor, but the challenges are immense. Funding is one of them. Speaking to The Guardian, Fisher says that the project would require around $10 million to map the Amazon over a period of three years. The entire world would take decades and perhaps over a billion dollars.
Getting permission to fly in the airspace of dozens of countries is not only logistically challenging but also politically challenging. For instance, Brazil President Jair Bolsonaro has time and time again proven that he is willing to undermine any scientific effort related to the climate.
But surmounting these obstacles is worth it, the scientists stress. It would be our ultimate gift to future generations, they say.
“We are going to lose a significant amount of both cultural patrimony – so archaeological sites and landscapes – but also ecological patrimony – plants and animals, entire landscapes, geology, hydrology,” Fisher told the Guardian. “We really have a limit time to record those things before the Earth fundamentally changes.”
You can learn more about Earth Archive in Chris Fisher's TEDx talk below.