Could you live with the same people (like them or not), grow your own food, and be confined to about 3.4 acres for two whole years? The inhabitants of Biosphere2 endeavored to do just that. There small world was supposed to produce its own oxygen from exchanging carbon dioxide with plants. Water was recycled through rain, filtering into the earth to be purified. They raised crops- rice was the main one. They had chicken or pork once a week, with fish every three months. They lived in what looked like a large college dorm room; that was their only privacy.
The experiment at Biosphere2 hoped to have scientists living in a totally self-sufficient world. The first group was sealed in and lived there for two years. Perhaps because the plants were not mature, oxygen levels were low and scientists had to give oxygen infusions. The second group was only sealed in for about six months due to political going-ons. Wikipedia has an account of the experiments.
The tour takes you through the various ecosystems plus underground to see the piping and lungs. A tropical rain forest was dense with vegetation. The ocean with coral reef, a mangrove wetland and savannah grassland lay between the rainforest and this fog desert where Chris is taking a photo with his tablet.
When we went below, we could see fish swimming in the ocean and around the reefs.We could see where they had grown crops. That area is being used for a new experiment to see what happens to water as it rains in the desert. They are constructing it and will begin experiments soon. As we walked along the outside, looking into the ocean and other areas, to the south, clouds over the Catalinas foretold of the rain that would drench Chris and me in about a half hour!
Biosphere2 is now run by the University of Arizona and all sorts of experiments are being conducted. This is a unique environment because one variable can be isolated and tested. For example, they have plants of the same species living in slightly higher temperatures than the other so they can see effects of global warming.
This is a fascinating place and one you should see in your RV travels. Look for discount coupons in tourist booklets. We happened to catch a Groupon special. From Tucson, you drive out Oracle or Highway 77 to milepost 96.5 almost to the town of that name. There is room to park RVs. Catalina State Park is on the way for camping as well as commercial RV parks. Jaimie Hall Bruzenak