Explain why acid rain, smog, ocean acidification, and global warming are indirect results of air pollution.

Answer:

Air pollution directly involves emissions entering the air. Acid rain, smog, ocean acidification, and global warming develop after pollutants interact with the atmosphere, sunlight, clouds, or oceans. For example, sulfur and nitrogen compounds can form acids in rain, pollutants can react in sunlight to form smog, carbon dioxide can dissolve in ocean water and increase its acidity, and greenhouse gases trap heat. These are indirect effects because they result from changes caused by the emitted pollutants rather than from the emissions alone.