Thread: Population
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Old 09-22-2011, 12:06 AM
robj3 robj3 is offline
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Join Date: Dec 2010
Location: Newcastle NSW
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Matt, you wrote:
Quote:
I'm going to go with a total North American population
(canada, US and Mexico) of about 20 to 25 million. (100K live in the Wisconsin Peninsula)
I think this is a reasonable mid-range estimate.

Starting with 1989 populations:
U.S. 248M
Canada 27M
Mexico 82M

95% mortality at 1 year -> 17.8M survivors

Reverting back to medieval or earlier levels of population growth (400 years for doubling implies ~0.175% p.a. growth; 150, ~0.467%) isn't unreasonable given the collapse of agriculture, disease and the effects of environmental contamination (decreased fertility as well as greatly increased mortality from all causes).

Using 0.175% p.a. I get 23.1 million at 150 years post.
Using 0.467% p.a. gives you 35.6 million, natch.

Quote:
Rich 5/KFS: 2 million people (including slaves) live in what was once Kentucky, most of Tennessee and part of Alabama
I think this is a very reasonable population estimate; you can't get much
lower unless the KFS is a garrison state like North Korea, or in a state of wartime mobilization - which seems unlikely. If the KFS is less militaristic, it pushes the required population up above five million (using countries in a wide variety of conditions as a guide).

As for the geography, it's not much of Alabama, just the upper part (because the Tennessee R. forms the southern border). I can shoot a map your way if you like (827 x 812kb jpeg, 434kb based off U.S. National Atlas map).

ArmySGT wrote:
Quote:
Wayyyyyyyyyyyyyyy more than I would put forth.

There is no major agriculture to support that many.
Maybe. I think this is a lower bound. Here's why:

The absolute lower bound is 0.01 people per square km - hunter gathering levels of population density or ~0.01 x 24,709,000km^2 = 247,090 or about a quarter of a million people.

Agriculture really boosts carrying capacity.
Pastoralism gets you to 1 person per square km.
Shifting farming (slash and burn) gets you to 10.
Traditional farming (pre-industrial agriculture) gets you above 100.
Industrial farming allows densities >1000 per sq. km

(V. Smil, Feeding the World, fig 1.2)

18.6% of the U.S.'s area is arable.
5% of Canada's area is arable.
12.6% of Mexico's area is arable.
Overall - 11.5% of land area, with another 11% for pastures.

As an upper bound using the arable land and pasture percentage and the above values I get:

Pastoralism (cattle, goats, sheep, etc, on arable and pasture land): 5.5 million
Shifting farming (arable land only): 27 million
Traditional farming (arable land only): 270 million
Industrial farming (arable land only): 2700 million

Army SGT:
Quote:
Five years after the Big Bang, how many of that 5% are still alive?
If you're proposing a two-log (99%) kill or more then that makes the Project extremely valuable in reconstruction. I think the rate of the dieoff levels out, which brings us back to something closer to the numbers above. Call me an optimist.

99% mortality at 5 years implies 3.56 million North American survivors.
Using 0.175% p.a. I get 4.6 million at 150 years post.
Using 0.467% p.a. gives you just under 7 million.

Quote:
I just think that in any place that is that well recovered is not going to need the Project, even going so far as to being hostile to the Projects meddling.
Trade can be quite a sweetener, especially when you have:
- fusion power
- universal antidote/antibody
- inertial navigation/geospatial information systems (AutoNav)


Rob
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