Biosphere 2: THE CITY OF ORACLE, ARIZONA — A traveler enters a coastal fog desert that reaches toward a savanna through the door of a glass pyramid, leaving the arid heat of Arizona behind.
A rocky shore is lapped by a Lilliputian ocean. A corridor leads to a humid rain forest with 90-foot-tall vine-necklaced trees.
Scientists can experiment with scaled-down ecosystems in Biosphere 2, the world’s largest controlled environment dedicated to climate research, by turning off sprinklers and cranking up the temperature to learn about the effects of global warming in the real world.
The facility’s ill-fated 1991 maiden expedition to build an analog of a self-sustaining colony on another planet has cast a long shadow over it.
The huge terrarium (directed by the University of Arizona since 2011) is finally living up to its potential as a place for unique and dangerous research after some retooling and success,
high-profile studies—including one that demonstrated rising waters are harming corals.
Scientists are testing how tropical ecosystems will cope with late-century heat and drought in a half-acre rain forest.
In the enclosure’s million-gallon ocean, researchers intend to test radical coral reef restoration methods soon.
In March 2022, the operation will reveal a Mars analog, which would fulfill the founders’ aim of recreating a plant-filled environment on a deadly alien world.
Biosphere 2 is essentially a time machine that can simulate a climate-changed Earth “by adjusting the quantities of chemicals in the atmosphere to those that we predict may exist in the future to see how the world might fare,” according to Joaquin Ruiz, the facility’s current director.
DIFFICULTIES IN THE PAST
On September 26, 1991, a crew of eight, including a physician, botanist, and marine biologist, began a two-year residency within Biosphere 2, a 3.14-acre terrarium.
The structure, which serves as a prototype for an interstellar dwelling, was designed by a counterculture theatre group that teamed up with capitalists to form Space Biosphere Ventures.
It was supposed to be a hermetically enclosed ecosystem with multiple biomes, 3,000 plant and animal species,
and a farm to provide all the air, water, and food the “biospherians” needed.
Jane Poynter, one of the early biospherians and creator of spaceflight company Space Perspective, says, “At the time, a lot of scientists thought it literally couldn’t be done, that the whole thing would turn into green slime.”
There was no filth in the enclosure. After a year, however, the oxygen levels had dropped to dangerously low levels, the farm was not producing enough crops, and the crew was suffocating and starving.
Some members of the Space Biosphere Ventures management team pumped oxygen into the building and utilized a CO2 “scrubber” to remedy the problem without exposing their efforts to the public.
When the truth came out, scientists lost faith in the mission, and the press mocked it. Some people still think it’s unjust.
“It was silly that the media depicted it as a failure because it entirely missed the point that it was an experiment,” Poynter says, adding that the purpose was to learn from the difficulties that arise in a human-made biosphere.
The failure, according to numerous current Biosphere 2 employees, was due to a lack of transparency rather than a lack of oxygen.
What went wrong taught scientists something important: the soil was too rich in organic matter, and its teeming bacteria ate up too much oxygen.
Initially, the researchers were unable to locate the extra carbon dioxide that those microorganisms should have produced as a result of their oxygen consumption.
They eventually discovered that it had chemically fused with the building’s concrete.
“It was like a light bulb went out,” recalls John Adams, the current deputy director of Biosphere 2.
“They could trace [carbon] where it was going and where it was being kept, molecule by molecule, in ways they couldn’t outside” in the actual world.
When Columbia University took over Biosphere 2 from 1996 to 2003, researchers learned that they could manipulate CO2, heat, and precipitation to anticipate future levels and test the effects on various biomes inside this controlled mini globe.
“A lot of people thought this was an excellent tool because you have a complicated system that you can completely close and risk damaging while learning how stressed systems behave,” says Klaus Lackner, director of Arizona State University’s Center for Negative Carbon Emissions, who is not affiliated with Biosphere 2.
“The difficulty is ensuring that it accurately reflects a real system.” I believe that one can take that path, and some of that [research] is now underway.”
PERSPECTIVE ON THE FUTURE (biosphere)
Christiane Werner, an ecosystem physiologist at the University of Freiburg in Germany, investigated how tropical plants and soil share nutrients to defend themselves from climate change—and what happens when such support systems fail.
Deforestation and climate-related tree death are changing rain forests like the Amazon from carbon storage sites to major greenhouse gas emitters, according to many recent studies.
Werner’s mission is to figure out what triggers these tipping points. As a result,
researchers may be able to produce more accurate climate projections and design more successful replanting strategies.
Werner’s team injected traceable versions of carbon and hydrogen into the glass-domed rain forest, then shut off the sprinklers for a 9.5-week “drought,” tracking where the elements went.
“That’s never been done before,” she continues, “and Biosphere 2 is the only place on Earth where you can do such an experiment because you can manage a fully established forest.”
It would have been impossible to conjure a two-month dry spell in the Amazon, and the chemical tracers could have fled anywhere, she points out.
The details of the soon-to-be-released findings are being kept under wraps,
but Werner thinks the most important takeaway was the diversity of plant species responses to stress.
“It buffers the whole forest because they have various functional responses,” she argues, adding that biodiversity is crucial to keeping forests stable throughout the climatic change.
Other experiments in Biosphere 2’s rain forest have yielded encouraging results.
In a study published in Nature Plants in 2020, Michigan State University ecologist Marielle Smith and her colleagues turned up the thermostat on the tropical flora and discovered that it was more resistant to extreme heat than many had expected.
Researchers at the facility’s small ocean are collaborating with Seed Health, a microbial sciences startup,
to provide probiotics to corals to determine whether they may prevent bleaching (which occurs when heat-stressed corals expel the symbiotic algae that help feed them).
The researchers are also working on a program to test “super corals,” which have been bioengineered to be resistant to heat and acidity.
“You can’t get permission to undertake that study if you’re in Miami or Hawaii because there’s a risk that genetically modified corals may end up in nature,” says Chris Langdon, a University of Miami marine biologist who serves on Biosphere 2’s science advisory group.
“Because Biosphere 2 is in the middle of the desert, there is no possibility of anything escaping.”
Langdon is no stranger to the oceans of Biosphere 2. He worked there in the 1990s and discovered for the first time that ocean acidification causes corals to dissolve due to a lack of calcium.
He also believes the massive tank would be an ideal place to test a leading proposal for achieving negative carbon emissions: increasing the ocean’s pH by adding dissolved rocks, which would increase the water’s ability to extract carbon dioxide from the atmosphere.
Not all of Biosphere 2’s projects are concerned with climate change. Its so-called Space Analog for the Moon and Mars (SAM), which is presently being built, “is very much, on a scientific and even a philosophical level, identical to the original Biosphere,” according to SAM director Kai Staats.
SAM will be a hermetically enclosed home, unlike previous space analogs across the Earth.
Its main goal will be to figure out how to move away from mechanical means of producing breathing air and toward a self-sustaining system in which plants, fungi, and humans produce a precise balance of oxygen and carbon dioxide.
In SAM’s greenhouse, which is painted and colored to obscure the sun and replicate the poorer lighting on Mars, visiting researchers will hydroponically cultivate fruits and vegetables.
They’ll also try to make fruitful soil out of regolith (crushed rocks that look like dead Martian basalt).
This could have ramifications for restoring Earth’s devastated landscapes.
And, given the dangerous state of Earth’s environment, Staats hopes that the scientists who live in SAM will have the kind of epiphany that Linda Leigh, one of the early biospherians, described to him.
“She explained that in such a closed setting, you can’t help but be conscious of every breath you take, every glass of water you ingest, and every bit of food you eat,” he says. “It all comes back to you.”
