Prospects For A Declining World Population

"Increasing urbanization should also help the environment...City dwellers tend to use energy and other resources more efficiently, and have less direct impact on untrammeled landscapes like forests.

Much depends, however, on how those urbanites live, and think... On the minus side, some benefits of urbanization could be offset by a drop in the number of people per household. That means more households, more urban and suburban sprawl, and less efficient use of resources...Also on the minus side: Even if the human population begins to decline after 2050, global warming, which is caused by the buildup in the atmosphere of so-called greenhouse gases like carbon dioxide, is projected to cause major disruptions in the environment."

Thanks to Nathan Bush