Acid rain is one of the most destructive environmental threats to forests and their inhabitants. From weakening trees to harming wildlife, this invisible danger is reshaping entire ecosystems. Learn ...

Pennsylvania is a leader in acid rain in the U.S. Acid rain has long been known to be a threat to streams, forests and human health. The 1990 Clean Air Act, which targeted key pollutants ...

A forest once grew here ... warming that lasted millions of years." The short-term effects alone—cold, darkness, and acid rain—would kill plants and photosynthetic plankton, the base of ...

Reduced visibility and haze are primarily caused by soot, which also damages forests and crops by reducing nutrients in soil. Sulfur pollution is primarily released into the air by burning coal. It ...