This article proposes and evaluates four hypotheses about US pollution and environmental policy over the last half … century. First, air and water pollution have declined substantially, although greenhouse gas emissions have not. Second …, environmental policy explains a large share of these trends. Third, much of the regulation of air and drinking water pollution has …

This article proposes and evaluates four hypotheses about US pollution and environmental policy over the last half … century. First, air and water pollution have declined substantially, although greenhouse gas emissions have not. Second …, environmental policy explains a large share of these trends. Third, much of the regulation of air and drinking water pollution has …

quarters of the world. Two sections deal with purely atmospheric issues, air pollution near the earth’s surface and depletion … of ozone in the stratosphere. These sections are followed by a closer look at water pollution and water management. A …