By Cat DiStasio

Today's architects are imagining the cities of the future as building styles fall in and out of fashion and construction materials evolve. As urban centers get more crowded and polluted, a number of forward-thinking designers are responding with concepts for self-contained super cities that reach up instead of out -- sometimes up to 2.5 miles high. The resulting designs incorporate renewable energy, indoor farms and living space for thousands of people, with the idea that self-sustaining and self-contained communities can exist outside the constraints of climate change without contributing to it further.