When it comes to population density, Manhattan and Greenland represent the two extremities. Manhattan, with population nearing 1.6 million in slightly less than 23 square miles of land, the population density is 69,467.5 / square mile, according to the US Census Bureau. Now onto the other end, Greenland's land area is 2,166,086 square km, according to the CIA World Factbook. According to the same source, the latest population estimate is 57,695.
To first convert to the same units, Manhattan's population density is 26821.55 per square km. For Greenland, the same figure will be 57,695/2,166,086 = 0.0266355999 per square km. The difference then is 1,006,981.26 or 7 orders of magnitude. To put that into perspective, since Manhattan's population is 1.6 million, under Greenland's population density, slightly fewer than 1.6 people will be living in entire Manhattan. Wouldn't that solve the city's congestion issues?
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