ABSTRACT
Do you ever think about atmospheric air? Unless you are an air scientist, an air technology specialist, or a practitioner of air science, probably not. The rest of us? No, not really. We usually only think about air, the air we breathe, when there is not enough of it to breathe or when it offends us. Air, like water and soil, is simply one of those things that are all around us. Air, water, and soil are everywhere and seemingly limitless. We breathe air, we drink water, we plant our crops in soil (and are sometimes interred in it). These things are just out there, all three of them-especially air, which literally enshrouds the planet we live on. On the average, we each need at least 30 pounds of air every day to live, but we need only about 3 pounds of water and less of food. A person can live about 5 weeks or so without food and about 5 days without water, but only 5 minutes without air. Why don’t we give air a second or even a rst thought? Normally, we don’t-and this is somewhat surprising when you consider that if we take our air away, life ends. Simply, air is necessary for the survival of most life forms on Earth.
