MELISSA BLOCK, host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Melissa Block.
MICHELE NORRIS, host:
And I'm Michele Norris.
Time now for Climate Connections, our yearlong series in partnership with National Geographic. And this month, our focus is on drought.
BLOCK: If forecasts of global warming are correct, the Southwestern U.S. is one place this may happen. The region is in the midst of a severe drought that began in 1999. And it could be headed for a long period of even drier conditions.
To try to understand just how to big an impact this could have, scientists are looking to the past as well as to the future. Today, we visit a thousand-year-old ghost town of sorts. The once powerful civilization that lived there disappeared in the face of drought.
NPR's Richard Harris has our story.
RICHARD HARRIS: Chaco Canyon is a stark and breathtaking ruin nestled under soaring, red sandstone cliffs. It's North America's answer to the Incan city of Machu Picchu in Peru, only older. And for climate scientists Jonathan Overpeck and Julie Cole, it was worth the journey, kids and all, to this remote corner of northwestern New Mexico.
Mr. G.B. CORNUCOPIA (Park Ranger): Okay.
Professor JULIE COLE (Department of Geosciences, University of Arizona): Hi.
Mr. CORNUCOPIA: Hi.
Prof. COLE: I'm Julie.
Mr. CORNUCOPIA: Julie. And I'm G.B.
Prof. COLE: Nice to meet you, G.B.
Mr. CORNUCOPIA: Nice to meet you.
HARRIS: G.B. is park ranger G.B. Cornucopia. And he's taking these professors from the University of Arizona on a tour of a site of a major climate catastrophe. Here, a civilization grew and thrived for centuries before disappearing in the face of a 50-year drought.
Jonathan Overpeck hefts his 5-year-old son, Jackson, onto his shoulders.
Professor JONATHAN OVERPECK (Department of Geosciences, University of Arizona): Well, once a lot of people lived here, Jack, or at least came here to visit. And then they went away. And they have a lot of ideas why they went away, but no one knows for sure. And one of the reasons we think they went away was, in part, because it got dryer. And it got so dry that it was difficult to live here.
HARRIS: Over the course of 300 years, people known as the Anasazi built more than 150 large buildings under these cliffs. But whether they were living quarters, temples or something else entirely is a mystery.
Cornucopia leads the family toward the ruins of one of the most impressive of these structures, a great house called Bonita.
Mr. CORNUCOPIA: So some have referred to this, where we are now, as the edge of downtown Chaco.
Prof. COLE: And it was abandoned, what? Late 11th century something like that?
Mr. CORNUCOPIA: By 12, 1300, everybody was gone.
Prof. COLE: OK.
Mr. CORNUCOPIA: The original builders' last set of building phases were early to mid-1100s.
HARRIS: Bonita was once four or maybe five stories tall. The walls look like intricate mosaics, testament to the engineering and artistic talents of the Anasazi. Little is known about these people. But they were traders, astronomers, and above all else, master builders. It's easy to draw parallels from Chaco to life in the Southwest today. Once again, there's a thriving civilization. Once again, people are completely dependent on scarce water resources. And once again, there's the threat of a devastating drought - more about that in a minute.
Prof. COLE: So what do you want to do here, Jackson?
Mr. JACKSON OVERPECK: Let's go in.
Prof. OVERPECK: It's great idea.
Mr. CORNUCOPIA: (unintelligible) after my own heart.
Prof. OVERPECK: I want to take you into that room where you have an existing, intact ceiling.
Mr. OVERPECK: Who wants to explore with me?
Mr. CORNUCOPIA: Let's go, Jackson. Here, lead the way, okay? Yeah.
HARRIS: We ducked through a T-shaped doorway that's sized just right for a 5-year-old.
Prof. OVERPECK: Not much of a door.
Mr. CORNUCOPIA: Oh, it's a perfect door. What are you talking about? It's just fine. That door worked quite well then. It works quite well now.
HARRIS: We looked up and just over our heads is a ceiling made of logs, which had been carried by hand to this place from 20, 30, maybe even 70 miles away.
Prof. COLE: Wow. So why do you think that they built their big structures here and not where the wood was?
Mr. CORNUCOPIA: That is the question. Why Chaco? We don't know. It could be almost anything. Some, it could be some emotional, spiritual reasons, psychic reasons, a series of dreams or something that happened. It could be anything that - we'll never know because there's no written language.
Mr. OVERPECK: Should we just continue on?
Prof. OVERPECK: Sure.
HARRIS: As we walk through the maze of rooms, we find many too small and airless to be used as sleeping quarters, but too big to be used for storing food for a settlement of this size.
Prof. COLE: Ouch.
Mr. CORNUCOPIA: You all right? Did somebody bump their head?
HARRIS: Cornucopia points out that some of these rooms are dramatically over-engineered, using far more precious wood than necessary. A clue, perhaps, that the very act of building this structure was itself a ceremony. Is this place equivalent to the Great Pyramids of Egypt or Las Vegas?
Mr. CORNUCOPIA: They just might have been considered a wacko place for its time.
HARRIS: But one thing's for certain. They abandoned these elaborate buildings in the midst of a 50-year-long drought, which must have made life here, in a spot that was already parched, even harder.
Mr. OVERPECK: Can you tell me more about that thing, why they went away?
HARRIS: Jack looks down from Jonathan Overpeck's shoulders expectantly.
Prof. OVERPECK: Why do people need to live? Let's think.
Mr. OVERPECK: Water?
Prof. OVERPECK: Water's a big one. They didn't have the water they need. So that must be one reason why they had to leave. What's another thing that people need to live?
Mr. OVERPECK: Food.
Prof. OVERPECK: Food. And…
HARRIS: He's sharp.
Prof. OVERPECK: …you got to grow the food somewhere. And it sounds like they used to eat corn, beans and squash here. And so those all need water.
Mr. OVERPECK: Everything died.
Prof. OVERPECK: Or maybe, yeah, it's just with the drought. There wasn't enough growing of the wood, the trees to produce enough wood to keep all this people warm. So that might have made it rough, too.
Mr. OVERPECK: Because of global warming?
Prof. OVERPECK: Good question. The reason we're asking all these questions, Jack…
Mr. OVERPECK: Come on, dad.
Prof. OVERPECK: Because we're worried about global warming, what it might do to the Southwest.
Mr. OVERPECK: Yeah.
Prof. OVERPECK: And it might be like when these guys left.
HARRIS: This is not as farfetched as you might think. The southwest is in the midst of a drought that started in 1999. And if forecasts of global warming are correct, the region could end up in a drought that's even longer and more severe than the one that forced the Anasazi to abandon Chaco Canyon. Jackson's mother, Julie Cole, can't help but see that parallel.
Prof. COLE: I have often imagined the streets of Tucson or Phoenix as abandoned. And it's a bit scary to try to place that in the context of seeing something like this. You think that the place that's the center of your region, the biggest city around, could never crumble and fall, and yet, here it has.
HARRIS: Of course, we have more advanced technology now, not only to predict droughts, but to adapt to a changing climate. That said, a permanent drought in the Southwest would surely force some changes in the way people live. Julie Cole and Jonathan Overpeck say it's time to start thinking about that now.
Richard Harris, NPR News.
NORRIS: And you can see and hear more reports on climate change at npr.org/climateconnections, and also in this month's National Geographic magazine.