Each drives the others, and if one is changed all the others change. In the past the earth has maintained a balanced system. Each of the icons in the model is explained. The mountains of Arizona average about 4000 kilocalories of sunlight falling on a square meter per day. Under the glass and structure of Biosphere 2 the yearly average is about 2000 kilocalories per square meter per day.
Sunlight is essential for plant production of food and oxygen.
The more sunlight, the more photosynthesis. In the process of photosynthesis, carbon dioxide, water and sunlight combine to make oxygen and organic biomass . In their green cells they use sunlight and carbon dioxide to produce oxygen and plant biomass. This icon represents all the humans in Biosphere 2 and simply requires you to input a number. The default value is 8 representing the original total of Biospherians in the 1992-1993 experiment.