The human population of the earth is large and is increasingly rapidly. According to the 1991 Rand McNally World Atlas, the population in 1900 was approximately 1.6 billion. This increased to around 2.5 billion in 1950, and more than doubled over the next 40 years to exceed 5.2 billion in 1990.
Are there already too many people in the world, or can the earth comfortably absorb even larger numbers of humans? This is a crucial question that can be addressed from a governmental, scientific, or religious perspective. Not surprisingly, as is the case for most complex issues, there is considerable disagreement.
Partisans on one side or the other of complex public policy issues often employ metaphors in an attempt to reduce the issue into terms to which the average citizen can relate. For example, President Reagan once characterized the size of the U.S. federal budget, on national television, by giving the height of a stack of dollar bills equal in value to the budget.
A common tactic when discussing the question of global population is to calculate how much space each person would have if, say, New Mexico were evenly divided up among all the people on earth. In this lesson, we will calculate how many square feet each person would have if the earth's entire surface were divided up this way.
Ultimately, this is a rather simple calculation: we simply divide the surface area of the earth by its total population. Nevertheless, we will pursue this question in detail because: