Metin Bektas's Blog: Metin's Media and Math - Posts Tagged "surface"
How Much Habitable Land Is There On Earth Per Person?
What is the total area of habitable land on Earth? And how much habitable land does that leave one person? We’ll use the value r = 6400 km for the radius of Earth. According to the corresponding formula for spheres, the surface area of Earth is:
S = 4 * π * r^2
S = 4 * π * (6400 km)^2 ≈ 515 million square km
Since about 30 % of Earth’s surface is land, this means that the total area of land is 0.3 * 515 ≈ 155 million square km, about half of which is habitable for humans. With roughly 7 billion people alive today, we can conclude that there is 0.011 square km habitable land available per person. This corresponds to a square with 100 m ≈ 330 ft length and width. Is that a lot? I don't know, I'll let you be the judge of that ...
S = 4 * π * r^2
S = 4 * π * (6400 km)^2 ≈ 515 million square km
Since about 30 % of Earth’s surface is land, this means that the total area of land is 0.3 * 515 ≈ 155 million square km, about half of which is habitable for humans. With roughly 7 billion people alive today, we can conclude that there is 0.011 square km habitable land available per person. This corresponds to a square with 100 m ≈ 330 ft length and width. Is that a lot? I don't know, I'll let you be the judge of that ...
