Neil Reynolds has a fun piece on why good old Mother Earth is quite capable of sustaining many more people, here.
For that matter, though, it was once said – most famously, back in the 1970s – that the world’s population could fit comfortably into Texas. As it happens, this apparently idiotic assertion has been fact-checked once again. Here (from the Simply Shrug website) is the methodology and the math.
The global population is roughly 6.8 billion people. For this exercise, say seven billion. Use Metropolitan New York (population: 8.3 million) as a guide to tolerable density. With an area of 790 square kilometres, the Big Apple population density is 10,500 people per square kilometre.
How much land would be required to accommodate seven billion people with the same density of population that New York already has? Answer: 666,265 square kilometres. But New York City is already taken. Where could you find space for the rest of the world’s people? As it happens, Texas fits the bill perfectly: The Lone Star State has 678,051 square kilometres of land – or roughly 10,000 square kilometres more than needed.
He also has numbers for food and water needs, if you’re the nitpicky type. If you’re not getting the reference in the headline, please go here for the explanation.