This map from Per Square Mile illustrates how big a city of 7 billion would be by comparing it to the population density of various cities around the world.
For example, if 7 billion people were placed in a high population density like the New York metro area (America's densest), the city would take over the entire state of Texas. With an area with much more urban sprawl, like Houston, the city would have to cover most of middle America.
What the map doesn't include, however, is the city's real limits (things like the amount of water sources, farm land, and other resources the population would need to sustain itself). Tim De Chant, who originally created the map and wrote about it a few years ago, said measuring the ecological footprint would prove "maddeningly difficult" for the subset of cities he used.
A separate map, however, does include ecological footprints for 9 different countries.
More from GlobalPost...
THE WEEK'S AUDIOPHILE PODCASTS: LISTEN SMARTER
- Here comes the Pentagon's newest space plane
- 43 TV shows to watch in 2014
- America's anti-feminist mega-corporations' toxic disregard for women must stop
- Did the media get Ferguson wrong?
- How did Rick Perry escape blame for the Texas Ebola outbreak?
- This week I learned the surprisingly dark origins of the Nobel Prize, and more
- Extreme haunted houses: Inside Halloween's most terrifying new trend
- Keira Knightley on Laggies, relationships, and surviving your 20s
- The U.S. is about to sell weapons to Vietnam. That's bad news for China.
- Gamergate might be gaming sexism's Waterloo
Subscribe to the Week