Ozone – is the primary ingredient of smog!

Nitrogen, oxygen, argon, water, vapor, carbon dioxide, and most other gases are invisible.

Clouds are not gas, but condensed vapor in the form of liquid droplets.

Ground based smog, which is visible, contains reactants of nitrogen and ozone.

Variable & Increasing Gases

Nitrogen and oxygen concentrations experience little change, but carbon dioxide, methane, nitrous oxides, and chlorofluorocarbons are greenhouse gases experiencing discernable increases in concentration. CO₂ has risen more than 18% since 1958. Fossil fuels are the biggest problem!