9781422285534

INTRODUCTION N orth America has the largest coal reserves in the world. Most estimates show that they will last for more than 200 years. But coal’s role as a popular fuel in North America is changing. One reason is that, when burned, coal is relatively “dirty.” It produces more emissions, as gases and particles, than do natural gas or petroleum fuels. The emissions include carbon dioxide, a major greenhouse gas that contributes to the process of global warming. This is affecting the

7 A corridor in a large coal mine. (Aniuszka/Dreamstime)