Biosphere 2

I can honestly say that only two venues on our entire Southwest road tour failed to live up to expectations. One of these was Biosphere 2. It’s a 3.14-acre (12,700 m2)[1] series of airtight structures built to test the concept of creating and maintaining a self-contained ecological system. Five buildings housed a series of artificially recreated environments ranging from a coral sea to desert terrain and jungle foliage.

The structure was notable for its innovative solution for coping with atmospheric expansion. During the day, heat from the sun caused the interior’s air to expand, while cooler night time temperatures caused it to contract. Building a sealed structure able to cope with these daily forces would have been prohibitively expensive. To solve the problem, large inflatable diaphragms in domes were used to store expanding gases that passed along two large passages between the domes and the main structure.

Over the course of three years, two teams entered the complex where they were sealed off from the external environment. Each team set out to demonstrate that it was possible to create enough oxygen and food within an artificial environment to sustain life indefinitely. The first mission lasted two years; from September 26, 1991 to September 26, 1993. Eight crew members participated.

A second mission followed on March 6, 1994, with an announced run of ten months but was terminated early after a series of nasty disputes, including a protest by participants from the first mission that climaxed in an act of vandalism. Since then the site has been used for experiments on a range of ecological questions including climate change and the natural water cycle.

The first mission generated mixed results. The agricultural system produced 83% of the mission’s total diet. This included a wide variety of crops such as bananas, papayas, sweet potatoes, beets, peanuts, lablab and cowpea beans, rice, and wheat. No toxic chemicals were used since they would quickly impact health. During the first year inside the eight inhabitants reported constant hunger. During the second year, applying lessons they’d learnt the crew produced an additional ton of food. Their average caloric intake increased and they regained some of the weight lost during the first year.

Of course, each experiment included moments of drama and many fascinating insights into the complexity of our planet’s ecosystems. Unfortunately, few of these insights were shared during one of the guided tours you take through the complex. Even more disappointing, the interior is currently in the midst of a drought experiment which has made much of its vegetation increasingly scrappy. Furthermore, many of the plants are now two decades old and thus showing their age.

The overall impression was rather shabby and our tour guide seemed far too keen to justify the complex’s current reason for being. Our tour’s only highlight was the discovery that fish in the artificial ocean are descendents of the site’s original population. They’ve never been fed or cared for and thus represents compelling proof that it is possible to create a sustainable, artificial ecosystem.