In the 1980s scientists made a frightening discovery-forests, lakes, and rivers all over the world were dying at an alarming rate. Then they found the reason: acid rain. For decades, the burning of fossil fuels had built up nitrogen and sulphur oxides in the atmosphere. When these gases joined with water vapor, the result was deadly acid rain. This book explains what acid rain is, what causes it, the damage it has done, and measures being taken to stop it.