Scarcity of Natural Resources
Definition As it becomes more apparent that the world resources will not be able to sustain our current way of living, it is only reasonable that humanity might change it for a more sustainable one. Such a change in our way of living can be expected to impact the way cities are, since they are a product or a function of it.
Enablers The fossil fuel reserves getting alarmingly scarce, which would enforce a change how energy is produced, and consumed. Access to clean water predicted as a problem for some regions of the world in 2025 could have a huge impact on the way we live now. Fluent water available only for a certain amount per day is only one possible example of how drastic that effect might be.
Inhibitors Ignorance of human kind is the main inhibitor for this driving force. It is possible that until 2025, no real changes occur in our lifestyles due to ignorance of future crucial problems.