A new threat is here, and scientists say there's no way to stop it, as even remote parts of the world are seeing microplastic ...

In the 1970s, acid rain was one of the most serious environmental threats in North America and Europe. The air was so laden with pollution from coal power plants and cars at the time that it turned ...

Erosion transports the fragments away ... forming an acidic concoction that dissolves rock. For example, acid rain dissolves limestone to form karst, a type of terrain filled with fissures ...