EARTH: Neutralizing the rain

In the 1980s, acid rain was a big topic of conversation. Everyone knew about it. Today, just a couple of decades later, it's all but been forgotten. Why and how did this happen?

As EARTH explores in the July issue, the problem of acid rain has largely been solved. The solution started with congressional amendments to the Clean Air Act in 1990 that called for government regulation of sulfur dioxide emissions, a known cause of acid rain. Two decades later, sulfur dioxide emissions have been halved and previously damaged waterways and forests have largely recovered. However, after much success in the battle against acid rain, challenges still remain.

With the sudden and successful reduction of sulfur dioxide, new players have emerged in the battle against acid rain, changing scientists' understanding of the nature of the problem. How will these new elements alter atmospheric cycling? Is continued monitoring necessary in the fight against acid rain? Read the story online at www.earthmagazine.org/article/ … in-challenges-remain

Read this story and more in the July issue of EARTH Magazine, available online now at http://www.earthmagazine.org. Tackle the five outstanding questions in earth science; avoid dangerous microbes at the beach; and learn what Congress is doing to fight threats to domestic infrastructure from sea-level rise all in this month's issue of EARTH.

Provided by American Geological Institute