The geographical location of economic activity within the United States has important implications for carbon mitigation. If households clustered in California's cities rather than in more humid southern cities such as Memphis and Houston, then the average household carbon footprint would be...

Over the last thirty years, even as China's economy has grown by leaps and bounds, the environmental quality of its urban centers has precipitously declined due to heavy industrial output and coal consumption. The country is currently the world's largest greenhouse-gas emitter and several of the...