Track urban emissions on a human scale: cities need to understand and manage their carbon footprint at the level of streets, buildings and communities, urge Kevin …


Cities are taking steps to combat climate change, given the scant progress made by international treaty negotiations. Los Angeles, California, home to around 4 million people, has one of the most ambitious targets: to reduce greenhouse-gas emissions by 35% below 1990 levels by 2030. The city has calculated its carbon’footprint’and found that road vehicles constitute 47% of total carbon dioxide emissions, and that electricity consumption constitutes 32%(1). So how should Los Angeles target its policies?Knowing that certain roads, types of…