Humidity and Precipitation

The amount of moisture in the air can have an impact on air quality. Depending on the conditions, fog and rain can effectively help dilute some of the pollutants, thus aiding to clean the air. Cloudy skies can help scatter, reflect, and absorb solar and UV radiation as it enters the atmosphere. Through this process, the amount that reaches the ground is reduced and slows the production of ground-level ozone.

However, the same chemicals and compounds that pollute the air, such as sulfur dioxides and nitrogen oxides, can mix with the precipitation. When the rain falls to the surface, polluting soil and surface waters.

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