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Re: [cdn-nucl-l] RE: [Rad_Sci_Health] Climate Change and Nuclear Energy: A View from MIT's Kerry Emanuel
population, Rod Adams raises an important point when he says,
"Whenever I hear that, my skin
begins to get a bit itchy. Who do you think is qualified to begin
selecting the people who get to stay and those who have to leave? Who
gets to choose who has children and how many they
have?" The fact is, however, that
SOMETHING WILL limit the population growth rate to zero or below,
sooner or later. Let's hope that the "something" is
reduced family size in response to increasing standards of living (made
possible by nuclear power, of course), rather than continued and
expanding wars, pestilence, and starvation. Fortunately, as Randal
Leavitt points out, there are signs that the population trend is in the
right direction. But is it fast enough?
calculation (not particularly original) that anyone can do with a
financial calculator. Assume: (a) a population growth rate and (b)
a value for the earth's carrying capacity, in people per hectare of land
(including farms & forests, etc), and calculate the time to reach
that limit. If anyone finds an error in the calculations below,
please speak up.
Current population growth
rate (2006): 1.17% per year
Growth rate extrapolated to 2049 by U.S.
Census bureau: 0.49% / yr
1 hectare = 10,000 m^2 = ~2.5 acres
Global land area: 148.94 million sq km = 1.5E14 m^2 (including the
arctic and antarctic) = 1.5E10 hectares
Global population: 6,525,170,264 (July 2006 est.)—say
Current population density: 1.5E10 / 6.5E9 = 2.3 hectares/person =
0.43 people / hectare = 0.17 people/acre
That's a current 5.7 acres per person, including the person's
share of land for farm, forest, desert, ice, and permafrost.
Thus the last column in the following table assumes 40 people per
acre of global land area -- which would be quite a technological leap
from today's 0.17 people per acre.
what it would take to provide a decent standard of living to more than 1
person per hectare of land area, since today we're not doing very well
with fewer than half that many people..
Assumed Years to
reach Years to reach Years to reach
growth 1 person per 10 people
per 100 people per
%/yr (0.4 people/acre) (4 people/acre) (40
(I hope the table retains enough formatting to be
concentration of population in urban areas will continue to increase as
long as the population continues to grow.
At 07:57 AM 3/24/2007, Dan Meneley wrote:
Charles Pennington says it well.
Here is my tuppence: In the short term, whether or not climate
change is anthropogenic, we must do something to rebalance our energy
demand with the supply. Uranium energy is one of the solutions --
in fact, I think, the most important one.
However, taking over a steadily increasing load from the oil and
gas industry (for whatever reason) is an enormous task. I say that
we should encourage every alternative energy source, and every
conservation measure, that can pass the various acceptability
tests. If we do this then we just might make it through the next
century without massive hardship. We have no time for
The lead countries in moving away from fossil fuels and toward cleaner
alternatives must be those whose citizens can afford to
change. We can hope that oil and gas will, with a
steadily decreasing demand, then become cheap enough that those who
cannot afford to change can at least afford to live.
Along the way we must also deal with the fundamental problem of excessive
human population. That will keep us busy indeed.