ABSTRACT
Reducing human greenhouse gas emissions to virtually nothing, as necessary to head off the worst global warming scenarios, will require radical transformations in energy and materials use. These subjects were virtually unknown to the nascent environmental movement at the turn of the twentieth century, and only entered the public consciousness in a major way in the 1960s and 1970s. Now, in the era of climate change, they are at the center of sustainability planning. Many other reasons exist for reforming energy and materials use as well, including pollution of air and water, problems with toxic chemicals in the environment, and environmental justice impacts on disadvantaged communities.
