[Odin]

Originally Posted by noodle

why are you showing me the earth at night? That doesn't really concern this topic. You ought to be showing this image instead...

the red is where it is densly populated. I think it's obvious that there is a lot of room left

Space is not the issue. Resources are the problem!

The problem with that map is that it only show space available, and does not give any indication of available food resources. I know I've seen a map of arable land, although I can't seem to find it at the moment. Until I do, let me offer this map, that gives a indication of how little of the land surface supports vegetation. If you notice, in particular in Europe and Asia, there is a strong correlation between the areas of high human population and areas of high vegetation. (sorry it's a rather large map)

http://www.nasa.gov/images/content/2...1_lrg_full.jpg

According to current estimates by the American CIA, calculates the total amount of arable land to be about 13% of the total land surface. Of that about 4.7% is currently being used for permanent crops. So we are using about 36% of the available land.

So yes there is room for growth, however with the uncertainties of the environment it is dangerous to substantially eat into the reserves this available land. Also, it is not unusual for arable lands to become depleted do to human activity and over farming. Especially in those areas where farming techniques are less sophisticated. So there is no guarantee that current arable land will be available for future use.