The atmospheric scales are global, mesoscale, regional, and local.

Carbon dioxide and other greenhouse gases such as methane and nitrous oxide can pollute the atmosphere on a global scale.

This leads to global climate change.

Sulfuric acid from coal-burning power plants can pollute the atmosphere on a regional scale.

This leads to acid rain.

The depletion of the ozone layer by CFC's can also do damage to the environment on a mesoscale/global scale.

Burning [forest and range] can also pollute the atmosphere on a regional/local scale.