What factors do demographers consider when they estimate how many people earth can support?

Question

What factors do demographers consider when they estimate how many people earth can support?

Answer 1

Historical economists use a metric consisting of people/square mile of land under agricultural production to determine level of innovation of a particular society at points in time. This is a pretty reasonable method to use as a foundation for calculating global population capacity. They make allowances for climate and arability of land. Typical calculations involve quality and quantity of land with the potential for agriculture, capacity for aquatic agriculture and level of technology.  What isn't usually accounted for are things like oxygen, fresh water and general mineral consumption.

Demographers calculating earth's support capacity are putting a number on a moving target given innovation is the key factor in both resource availability and resource consumption.  What is often neglected during the typical Malthusian hysterics over the earth's capacity to sustain population growth is that innovation drives increases in efficiency of resource procurement and use.  Some wiser people acknowledge this fact but suggest that the pace of innovation advancement may not always pass growth in consumption and population needs. To this, I would like to point out the following:

1) Unexpected discoveries change the known stock of resources - so we never really know what is available.

2) Technology increases the effective stock of available resources thanks to more efficient and effective deployment of the resources.

3) Technology reduces the costs of extracting the resources.

4)  Technology increases the effective stock of ALTERNATIVE resources.

5)  Slowing and speeding of economic growth changes estimations of future use.

Bottom line - most of the global demographic predictions are meant for discussion, political intimidation or for plain entertainment.  As for planning, your best bet is on human innovativeness and a hope that we are educating and motivating people with the right incentives to keep pace with the growing needs we have. Be critical about these capacity estimations because they usually have an intent beyond being accurate.

Answer 2

whatever it may be,

it must have something about the

factors in which a location is to

be as livable as possible.

concerning the density, it is simply like

estimating how many hairs can be

occupy a square inch of scalp.

Answer 3

Contrived ones.http://www.bibliotecapleyades.net/esp_so...