Chris Fisher: Archiving the surface of the earth LIDAR technology is an innovation in archeology and ecology that has uncovered lost civilizations. But archeologist Chris Fisher realized it could help track and study the effects of climate change.

What would we learn and what could we save, if we had a 3D-scan of the entire earth?

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It's the TED Radio Hour from NPR. I'm Manoush Zomorodi. And on the show today, for all eternity, how we are trying to preserve information forever. So far, we've talked about archiving the internet, putting data on DNA. And now for something a little different - what if we could archive the Earth? Our story starts with archaeologist Chris Fisher.

CHRIS FISHER: So in 2009, myself and my team of graduate students and other students documented an ancient city for the first time in central Mexico, which we now call Angamuco.

ZOMORODI: That ancient city that Chris found was massive.

FISHER: So it had served to preserve thousands of building foundations.

ZOMORODI: And that was so exciting but also terrifying because Chris would need years to excavate and map this site.

FISHER: I mean, this would have been my career, serving this one site. I'm super impatient, and I didn't want to do that.

ZOMORODI: So Chris asked a colleague for advice.

FISHER: And I'm like, dude, there's got to be a better way. And he's like, well, have you heard of this LiDAR technology?

ZOMORODI: LiDAR stands for Light Detection and Ranging. It's the sensing technology that self-driving cars use to scan and make maps of the terrain around them.

FISHER: But what we do is we use something called airborne LiDAR.

ZOMORODI: Using helicopters, planes or, increasingly, drones.

FISHER: And basically you have some sort of instrument. That instrument fires off a pulse of infrared beams, you know, hundreds of thousands of pulses in some instances. When one of those beams strikes something - could be the ground surface, it could be buildings, pyramids, roads, all of that sort of stuff - it returns back to the sensor and it gives you a measure of distance.

ZOMORODI: All that data creates a full 3D scan, a digital map. And that first map that Chris saw absolutely delighted him.

FISHER: In 45 minutes of flying, the LiDAR had collected 20 years' worth of normal archeological fieldwork. I actually started to tear up a little bit because I was like, oh, my God. This changes everything.

ZOMORODI: Chris became a specialist in using LiDAR in archeology, which is why, three years later, documentary filmmakers sought him out. They wanted Chris to look at their scans of a site in Honduras.

FISHER: You know, they needed some help interpreting them.

ZOMORODI: The scans seemed to show a lost city buried beneath the vegetation. Chris thought so, too, but he also wanted to be sure. And so they headed to Central America.


FISHER: We had to go verify that what we were actually seeing in the LiDAR images was actually on the ground. And to do that, these sites were so inaccessible that the only way to effectively get there was by helicopter.


FISHER: And so we entered this world that hadn't been visited by people for centuries.

ZOMORODI: Centuries?

FISHER: Centuries since it was last occupied in the prehistoric period.


FISHER: There are only a couple of entrances into the valley. And so we were able to fly through one of those gaps. And then the valley opens up, and it's just a sea of green. And we saw, below us, flocks of scarlet macaws.

ZOMORODI: Oh, it's beautiful.

FISHER: So it's just green, green, green. And then you have these brightly colored birds. And the contrast in the colors was just really mind-blowing. And I knew at that point that we were - this was different. We were in for something really amazing.

ZOMORODI: Chris and the team did, indeed, find evidence of a city that's now called the City Of The Jaguar. There were ancient house foundations, irrigation canals and a shrine.

FISHER: So we found a cache of objects at the center of the site, on the - that were left on the surface that were like a ritual closing of the site.


ZOMORODI: It was a huge discovery. And so the government got involved. Soldiers were stationed on site to protect it from looting. But 11 months later, when Chris came back for another visit, he was shocked at how different things looked.


FISHER: The tiny gravel bar where we first landed our helicopter was gone.

ZOMORODI: Chris Fisher continues from the TED stage.


FISHER: The brush had been cleared away and the trees removed to create a large landing zone for several helicopters at once. Without it, after just one rainy season, the ancient canals that we had seen in our LiDAR scan were damaged or destroyed. And the Eden I described soon had a large clearing, central camp, lights and an outdoor chapel. In other words, despite our best efforts to protect the site as it was, things changed. Our initial LiDAR scan of this City Of The Jaguar is the only record of this place as it existed just a few years ago. Broadly speaking, this is a problem for archaeologists. We can't study an area without changing it somehow. And regardless, the Earth is changing. Archaeological sites are destroyed. History is lost. We take for granted that our cultural and ecological patrimony will be around forever. It won't.

ZOMORODI: So the Honduran government brings in soldiers to make sure that other people don't come in looking for treasures.

FISHER: Right.

ZOMORODI: But in the process, they destroy other things that, probably, the naked eye would never know was there unless we were an archaeologist. And so when you realized that that was happening, did you say to yourself, well, thank goodness we have this original mapping of this area with LiDAR?

FISHER: Yeah. So my initial reaction was, oh, yeah, we've got these. We have the LiDAR images of them. But then my secondary reaction was, like, kind of an intense sadness. By documenting this place and understanding it and going to it, we'd actually fundamentally changed it.

ZOMORODI: So this - what do you do with sadness is always the question that I have.

FISHER: (Laughter).

ZOMORODI: And I feel like, you know, do you just say, well, this is what I - in my life's calling, this is what I do?

FISHER: Yeah, yeah.

ZOMORODI: Or do you think, huh, hmm.

FISHER: Yeah. You know, that made me realize how fragile the Earth is, how rapidly the Earth is changing due to the climate crisis and how much stuff there is left to discover. It took me several months to figure this out. But eventually I did come to the realization that I could do something, that due to the climate crisis, we're losing cultural and ecological treasures that we don't even know exist. And unless we document them, we will never know they exist.


FISHER: We've lost 50% of our rainforests. We lose 18 million acres of forest every year. And rising sea levels will make cities, countries and continents completely unrecognizable. Unless we have a record of these places, no one in the future will know they existed. Looking at my scans from Honduras and Mexico, it's clear that we need to scan, scan, scan now as much as possible while we still can. That's what inspired The Earth Archive, an unprecedented scientific effort to LiDAR scan the entire planet, starting with the areas that are most threatened.

Its purpose is threefold. No. 1, create a baseline record of the Earth as it exists today to more effectively mitigate the climate crisis. To measure change, you need two sets of data, a before and after. Right now we don't have a high-resolution before data set for much of the planet. No. 2, create a virtual planet so that any number of scientists can study our Earth today. Archaeologists like me can look for undocumented settlements. Ecologists can study tree size, forest composition and age. Geologists can study hydrology, faults, disturbance. Possibilities are endless. No. 3, preserve a record of the planet for our grandchildren's grandchildren so they can reconstruct and study lost cultural patrimony in the future.

ZOMORODI: OK, so your mind-boggling project is called The Earth Archive, and it requires, as you put it, that we scan, scan, scan the planet.

FISHER: Yeah. So this was the big idea. That's where I landed in that we have this technology to scan the Earth's surface and everything on it and curate it in perpetuity for our grandchildren's grandchildren. And these LiDAR records represent the ultimate conservation records 'cause not only do they record the ground surface, but they record all the vegetation on it, every tree. It would record the underlying topography. It would record the hydrology of places. We'd be able to see archeological sites in those zones. We would be able to see modern settlement change and roads and deforestation features and countless, countless other things. But the archaeology piece of this is probably the least important. The ecological piece is probably a lot more important. And so it really would be the ultimate baseline data set from which you could do other significant analysis.

ZOMORODI: Layer and layer and layer upon layer of information. I mean, that's - I love the way you described it. It's like a research sandwich that it's capturing.

FISHER: Exactly. And that's the amazing thing about these LiDAR records. Once you do the scan, it freezes the Earth and everything on it in time. And since it's a digital record, you can curate it in perpetuity, so it doesn't degrade like a photograph.

ZOMORODI: All right. How is this even possible? - because what you're talking about is a small plane flying over every square inch of the planet to scan it with a LiDAR ray. Can that be done?

FISHER: It absolutely can be done. Many wealthier countries are already scanning all of the lands within their borders. The problem is that countries that don't have those kinds of resources, which happen to be some of the countries that are most threatened, or even areas within the United States' populations that are sort of underserved by the government are not getting their area scanned in time.


FISHER: So we've just completed a really exciting project that we helped facilitate with the Yakutat Tlingit Tribe in Alaska.

ANDREW GILDERSLEEVE: We live in a dynamic, shifting environment. We find that the landscape is actively moving all around us.

ZOMORODI: This is Chris' partner on the project, Andrew Gildersleeve.

GILDERSLEEVE: I'm the chief executive officer of the Yakutat Tlingit Tribe. We're really the top of southeast Alaska on the Gulf. What makes us so unique is the fact that we have one of the few glaciers in the world that is actually growing a tidewater glacier.

ZOMORODI: Nearby, lots of logging is causing deforestation, especially on one particular island.

GILDERSLEEVE: It's made of gravel, and the trees are literally what hold the gravel together.

ZOMORODI: And that is jeopardizing the tribe's livelihoods, their land and their burial sites.

GILDERSLEEVE: So when Chris came onto the scene, we decided to move quickly, and we immediately moved to have a LiDAR scan of this barrier island. Now, this island is home not only to burial grounds and ancient village sites, it's also literally our protection from the Gulf of Alaska, from potential tsunamis.


GILDERSLEEVE: And with LiDAR, it immediately meant that this island could not only speak for itself and tell us its stories, it also meant that the logging operation was not going to get away with any of the destructive tendencies that they had in the past. We had recorded and collected everything with regards to the island, from the roots to the tops of the trees.


FISHER: They're seeing the changes in their landscape. They're concerned. And they want to use every technique they possibly can to ensure that they are practicing best standards for their continuing stewardship.

GILDERSLEEVE: LiDAR gives us an immediate and clear history. And as we live in this dynamic time and this dynamic landscape with the climate crisis and with the deforestation, with fisheries issues, tourism issues, we need serious data to really start answering big questions of the tribe. And the powerful part of that is I believe that when people can see it, when it's been recorded, that we as a people, fundamentally, won't allow it to happen anymore. It's only when these things occur out of sight, when there's no true record and when a story can't be told that this type of environmental degradation occurs.

FISHER: And it's also really exciting for us at The Earth Archive to help work with the Yakutat to build their own internal capacity to be able to, you know, understand and analyze the LiDAR data and use it to practice good conservation on their lands.

ZOMORODI: Yeah. You know, it makes me wonder, like, has anyone ever said to you, OK, that's great that you're going to scan this area, but how about just giving us the time and money to actually stop the climate change that is being inflicted upon us? Instead of showing us a snapshot of where we are, how about helping us fix it?

FISHER: Yeah, unfortunately, that's not possible. So any changes - I mean, we could all start living like "The Flintstones" today, and any changes we make are baked in for probably the next 20 or 30 years, at least, if not more. So unfortunately, at this point, the landscape is going to change and it's going to change pretty dramatically.

ZOMORODI: So depressing.

FISHER: I know. It is depressing, but we've got to fight, fight, fight to do the best that we can do for the generations that follow us.

ZOMORODI: Chris, I just want to, in the last few minutes, ask you, I mean, this is kind of a big change for you. You are an excavator, you're an archeologist, you're looking into the past. And now you have become more of a librarian archivist, preserving the future in some ways. Is that weird for you?

FISHER: It's totally weird. I mean, you know, I was trained as a field archaeologist. The longer my boots stayed in the closet, the more unhappy I would get. And now it's time to leave our boots in the closet and just buckle down and focus on recording the things that are being lost.

ZOMORODI: Do you think of yourself as leaving breadcrumbs of data for future humans now? Are you that person?

FISHER: I hope so. I mean, I hope. I fully expect that people will be going back through these LiDAR records that we're collecting today, 100 years from now, maybe centuries from now - who knows? - asking questions that we can't conceive of, using techniques that are beyond even anything that we could sort of come up with. And maybe my name will be in the metadata somewhere or The Earth Archive's name will be in the metadata somewhere. And that'll be my legacy.


ZOMORODI: Archaeologist Chris Fisher is the founder and co-director of The Earth Archive. You can see his full talk at And to learn more about the project, go to Many thanks to Andrew Gildersleeve, the chief executive of the Yakutat Tlingit Tribe, as well. And thank you so much for listening to our episode, for all eternity. It was produced by Andrea Gutierrez, James Delahoussaye, Katie Monteleone and Matthew Cloutier. It was edited by Sanaz Meshkinpour, Rachel Faulkner White and me. Our production staff at NPR also includes Fiona Geiran. Our intern is Susannah Broun and our fellow is Malvika Dang. Our theme music was written by Ramtin Arablouei. Our audio engineer was Alex Drewenskus and Stacey Abbott. Our partners at TED are Chris Anderson, Colin Helms, Anna Phelan, Michelle Quint, Jimmy Gutierrez and Daniella Balarezo. I'm Manoush Zomorodi. And you've been listening to the TED Radio Hour from NPR.

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