ORACLE, Ariz. — Plopped in the Sonoran Desert, just outside Tucson, Ariz., sits a massive, multilevel greenhouse that's probably best known as the inspiration for a Pauly Shore movie.
A slick, stepped-glass pyramid climbs out of the dusty scrubland, next to a series of white geodesic domes. The building would be at home in a midcentury world's fair.
But it's what's inside that's really eye-popping. Through a basement maze of whirring industrial equipment are mundane-looking doors that lead to the unexpected. A decades-old rainforest, soaked in humidity and teeming with plant life. A miniature manmade ocean, sloshing gently against a small shore. Not to mention the mangrove wetland and fog desert landscape. The structure reaches 91 feet at its highest point, covers more than three acres and contains 6,500 windows.
It's a living, breathing laboratory called Biosphere 2. Researchers created the facility in the late '80s and early '90s to see if humans could survive in an artificial, self-sustaining ecosystem. A group of eight people called "Biospherians" sealed themselves inside a terrascaped glass chamber for two years starting in 1991, where they farmed their own food, tended to livestock and ran experiments. But oxygen levels started dropping, absorbed by all the concrete used throughout the massive structure, and their personal conflicts became international headline fodder, instead of the science. A second mission started in 1994 but only made it six months.
The story of Biosphere 2, however, has evolved well beyond the late-night punchlines, tell-all books and the Pauly Shore movie Bio-Dome.
Texas billionaire Ed Bass spent some $150 million building Biosphere 2. But after all the attention and scrutiny, Bass and his team decided that the focus should no longer be on people living on-site, according to Biosphere 2 Chief Operating Officer and Deputy Director John Adams. It was then leased to Columbia University, which used Biosphere 2 to understand the impacts of carbon dioxide on plants. It is now owned and run by the University of Arizona. And today, scientists there are quietly plugging away at research they hope will help people adapt to human-caused climate change on Biosphere 1 — that is, Earth.
Myriad scientific papers, progress and lessons have come from Biosphere 2. But it's not an exact copy of our planet's complicated biomes.
"No matter how smart we think we are, you're never going to re-create Earth in its entirety," Adams said.
Here's a look at some of the experiments that Biosphere 2's scientists have dreamt up and are tinkering with in this big glass building in the desert.
Coffee and chocolate in the rainforest
Inside Biosphere 2's giant glass pyramid, tropical trees stretch 80 feet above the forest floor. Crazy ants, so named because of their erratic movements, scurry below.
The rainforest is less diverse now than it was when Biosphere 2 first started its experiments, said rainforest research specialist Jason de Leeuw. There aren't many animals beyond the ants and a few other creepy-crawlies. But some original hibiscus trees, pterocarpus trees and even a small coffee tree still stand.
These days, scientists are using the ecosystem, which includes an indoor waterfall and floodable stream, to measure the heat tolerance of cacao and coffee trees. The higher into the canopy you go, the hotter it gets, topping out at around 130 to 140 degrees Fahrenheit in the summer.
And the closed system and technology allows scientists to gather scads of data. "It's really one of the most heavily instrumented rainforests in the world," said de Leeuw. Scientists can even measure the minute daily expansion and contraction of the trees.
Justin Beslity, a post-doctoral student who has designed low-cost plant monitors for Biosphere 2, hopes his work can help coffee and cacao farmers throughout the world closely monitor their crops.
"So that people could understand how their trees are growing and whether they need to be increasing new irrigation or there's something else wrong with it, because coffee is a cash crop for a lot of people," Beslity said.
Their trees have produced some pods, and the scientists love the idea of starting up a coffee lab to show the process from tree to cup. They may even start selling Biosphere brew and chocolate, Beslity and de Leeuw said.
Fish in the desert
Biosphere 2's fog desert is the landscape that hews closest to what lies right outside the building. It houses agave plants, cacti and other desert plants. Currently, there isn't much experimentation happening in that desert — but that's about to change.
In early October, Biosphere 2 will receive endangered Quitobaquito pupfish to introduce into its habitat. The fish hail from Arizona's Quitobaquito Springs by the U.S.-Mexico border, where water levels dropped after the Trump administration began building a section of the border wall nearby in 2020, environmental news outlet Grist reports. Environmentalists had warned that construction could disrupt the habitat, though it's unclear if that was the direct cause, according to Grist.
A new stream with ponds and waterfalls flowing down the desert's midsection will house the creatures in a kind of "fish bank," where wildlife managers can withdraw them to repopulate the fish's native habitats. And the scientists plan to do research with the pupfish as well, de Leeuw said.
"We're interested in seeing if we put them in the different little ponds. Is there a genetic drift? Is there a change in their genes or things like that?" said de Leeuw.
The fish will also serve as scaly ambassadors for Biosphere 2's many visitors (more than 3 million since 1991, according to the organization), who will weave through the desert landscape.
Oceans of research
Biosphere 2's ocean ecosystem contains 700,000 gallons of sea water brought in from the California coast — more than an typical Olympic-size swimming pool.
Scientists suit up in scuba gear to explore its depths — up to 25 feet — and row boats across its surface. Below is an artificial reef made of rock, where fish, sea urchins, plankton and alga all live. The water is jostled by giant machines to mix the seawater.
Above it all hangs a big metal apparatus with lights that encourage coral growth in preparation for an upcoming experiment.
The mini ocean had coral when Biosphere 2 was built, but no longer does. In order to reintroduce it, Biosphere 2 has partnered with Coral Reef Arks, an organization that creates geodesic domes. They're made from PVC pipes suspended from the ocean floor and serve as platforms for the coral to attach to. The design allows the coral to float above degraded ecosystems, giving it a better chance of survival and the ability to repopulate degraded reefs, according to Coral Reef Arks and Biosphere 2 research specialist Lia Crocker.
She and the other scientists are trying to figure out the best geodesic dome designs and coral types to help repopulate bleached reefs.
"So the plan is to get the corals in here, have them hang out for a few months just to get a baseline of how they are in here and then ramp up the temperature over a few months," said Crocker.
Experiments for future resilience in "LEO"
It's far from the most impressive-looking ecosystem housed in Biosphere 2. But the Landscape Evolution Observatory, affectionately known as LEO, is brimming with interesting science.
"It looks simple at first glance," said Aaron Bugaj, the lead technologist at LEO. "But in the last 10 years we've seen a complex and beautiful landscape emerge."
LEO is made up of three metal trays, each bigger than a tennis court, filled with crushed basalt rock. Up above is a water system that's rigged to rain down on the basalt, as little or as much as the scientists want.
It was built in the space where the original Biospherians had farmed their food. The agriculture was cleared away about 15 years ago, after which 150 scientists came together to help decide what new experiment should go in its place, according to Bugaj.
They settled on studying ground water movement to better understand how a watershed changes under different conditions, such as the presence of various plant species or microbes, Bugaj said. The basalt is a stand-in for both early Earth and soil that has been depleted by factors such as years of growing a single crop.
"What's exciting about LEO and all of our biomes is that not only can we kind of peer into the future and answer questions about resilience ... we can also think about that idea of adaptation and can we develop novel methods that can increase adaptability in our ecosystems," he said.
The future of Biosphere 2
There are many other scientific projects happening at Biosphere 2. Outside the facility, crops have been planted under solar panels — a practice called agrovoltaics, in which solar power and agriculture coexist and mutually benefit each other. The panels shield the plants from sun overexposure, and the plants help cool the panels.
The facility is still examining how humans can potentially colonize other planets and has a radio telescope to communicate with satellites.
And visitors still file through its doors, both for the sense of nostalgia and for the work it's doing today. John Adams, the COO, said people come just to take in the enormity of it all.
"There's no other facility like this in the world," he said.
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