[Date Prev][Date Next]
RE: [cdn-nucl-l] RE: [Rad_Sci_Health] Climate Change and Nuclear Energy: A View from MIT's Kerry Emanuel
Very interesting indeed, including the clear
recognition in1978 of the potential role of breeder reactors (file
A global population of 10^12 people fits in between
columns 3 & 4 of the table below, at 66.7 people per hectare of land
area. The time to get there from here would range from 255 years at
a growth rate of 2% to 2,520 years at 0.2%.
It's a good thing that limit is still a few years off
-- the implied cultural and sociological changes are mind-boggling.
A well-coordinated global government (democratic?) would seem to be
necessary. One wonders, of course, about social stability when you have
millions of people collected at close quarters in a 3-D structure.
For one thing, horrendous acts of terrorism would seem possible, and even
attractive to an inevitable fringe..
But our more immediate challenge will be remaining
intact as we approach and pass 1 person per hectare (pop. 15 billion),
which will happen perhaps within the next century, and certainly within
the next two centuries unless we can keep the average growth rate .for
the next 200 years below 0.42%. According to the Census Bureau's
projections, the average growth rate between now and 2050 is twice that
At 07:56 PM 3/24/2007, Jaro wrote:
I thought you might find the attached
pdf document interesting....
- -----Original Message-----
- From: firstname.lastname@example.org.McMaster.CA
mailto:email@example.com.McMaster.CA]On Behalf Of George
- Sent: Saturday, March 24, 2007 8:04 PM
- To: Dan Meneley
- Cc: firstname.lastname@example.org.McMaster.CA
- Subject: Re: [cdn-nucl-l] RE: [Rad_Sci_Health] Climate Change and
Nuclear Energy: A View from MIT's Kerry Emanuel
on!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?
Regarding population, Rod Adams raises an important point when he says,
a 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.
- Basic data:
- 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.
wonder 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)
- (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.