Take a deep breath, city-dwellers: your greenhouse gas emissions are far less dense than those in the suburbs, according to a new report.
Environment & Urbanization studied emission rates around Toronto, and found a direct correlation between car-dependency and unhealthy air. Suburban neighborhoods with sprawling boulevards had about ten times the carbon emissions as dense city blocks where walking, biking, and buses are an option.
Temperature was another factor, with cold weather eliciting higher usage of fossil fuels. Warm cities like Los Angeles saw relatively low carbon emissions, although that city's climate and topography tends to make dirty air linger.
Emissions in Tokyo and Stockholm are very low, thanks to fees imposed on polluting vehicles. San Francisco is currently considering congestion fees of its own, which would reduce greenhouse gas emissions, reduce traffic, and improve safety.