The source of sulfur dioxide comes from burning of fossil fuels, and volcanic activity.

Sulfur dioxide can dissolve in rain water high up in the atmosphere, forming acid rain.

Acid rain speeds up the corrosion of buildings and structures made of limestone or reactive metals, like steel.

Acid rain makes water too acidic, which can be harmful to aquatic organisms.

Acid rain removes essential metal ions needed by plants, such as calcium, potassium, magnesium ions from the soil, affecting the health of plants.