Composition of the Atmosphere Air is a mixture of many discrete gases with their own physical properties in which different quantities of tiny solid/liquid particles are suspended. A. Major Components Composition of air varies depending on the time and place. If H20 Vapor, dust, and other variables were removed from the atmosphere, the makeup is very stable worldwide for an altitude of ~ 80 km. Ni and O2 make up 99% of clean, dry air. They are the most plentiful components, and important to life, but do not affect weather much. The remaining 1% is mostly Argon (0.93%) and other tiny quantities of many other gases. B. Carbon Dioxide (CO2)