Newsgroups: sci.environment

I wrote:
><
><I've argued that the equilibrium human population should be under one
><billion, call it a nominal 0.5 billion. The precise value depends upon
><many tradoffs and could range as low as 100 million or as high as one
><billion. But one billion should not be the target.
><
><This is about a 90% reduction of the human population below current 
><levels. It could be achieved by attrition alone (lowered birth rate)
><in less than two centuries without massive social upheaval. 
><
><We need to transition to a society in which most couples have one child.
><That is about the best we can expect, but it would be a substantial
><improvement. Perhaps there would be special incentives for childless
><couples. The sale of the child bonds would provide some income, though
<I have no idea how much.
><
><There is little chance that human numbers can be brought down to levels
><compatible with the prospering of other species in less than 1-2 centuries.
><Many extinctions *will* occur during that interval. The most we can hope
><for is to try to keep them down to perhaps <30% of the diversity of the
><biosphere. Also, reduction of the extinction rate to zero implies 
><significant amounts of habitat restoration within the next 1-2 centuries,
><not solely a reduction in human numbers. 
><
><Alan McGowen

Irv Chidesy wrote:
>
>	If each couple has, on the average, one child; we get to a birth
>rate that would sustain a population of one tenth our current population
>in just over 3 generations, or in about one century.  Then we have to shift
>to a birth rate of just over 2 children per couple, to sustain that population.
>By 100 years later all the excess old people will have died, and we will
>be at a steady state.

Dan Mocsny wrote:

>Lest I speak nonsense, let me do my arithmetic (well, logarithms,
>actually). Assuming a generation time of 33 years, 2 centuries is 
>about 6 generations. A 90% reduction in 2 centuries means that each 
>succeeding generation should be about .68 as large as the preceeding. 
>(.68 to the sixth power is approximately 0.1.)

As I suggested we need to move to a world in which one child per couple
is about average, in order to reach about 10% of current population within 
2 centuries, with a nearly stable age structure. 

Irv Chidesy wrote:

>	But consider the situation when we are ready to switch back from
>one to two children per couple.  There will be one dependent child, two
>working parents, four just retired grand-parents, taking care of say four
>bed-ridden great-grand-parents.  ( Some exageration for effect, perhaps. )
>One child per couple leads to an inverted population pyramid, and those
>in their working years are going to have to do a lot of work, and those
>who have outgrown their working years may not find their retirement golden.

Dan Mocsny wrote:

>This is slightly more than one child per woman surviving to adulthood.
>Since this is substantially below the birth rate in most parts of
>the underdeveloped world, I'm not sure how to achieve this without
>massive social upheaval. 

I didn't say it would be easy, or that it wouldn't involve great social
changes. But it needn't involve deliberate increases in the death rate.
Remember, though, that increases in the death rate are likely to occur 
anyway as the population peaks, and the higher the peak, the likelier and
larger such increases become. Some of the "downsizing" from the peak will 
come from deliberate reductions of birth rate, but some of it could come 
from unwished-for but likely increases in death rate. The more of the 
former we have soon, the less likely and less severe the latter will be 
later.

Perhaps "without social upheaval" was a poor choice of phrase: social
disturbance is inevitable in any case. I meant without deliberate 
violence, or "gas chambers" as someone put it.

As to how the birth rate of the underdeveloped world can be reduced, 
it cannot be done without major material improvements in the lives
of most people. But the material improvements most needed are not
out of reach: an adequate basic nutrition and basic health care, and
basic education and literacy, especially for women, and readily 
available birth control -- these are the main factors needed to 
induce demographic transition, and it is not beyond the power of
the developed world to see that these are provided. In addition to
this, intensification of global communications in every locale on
the planet is an absolutely critical prerequisite for a global shift
in values sufficiant to move to birth rates below replacement.

Irv wrote:

>Downsizing the population both gracefuly and quickly is not going most people
>to be easy!  There will be great need for sociological research to tell us
>how we can best downsize without disaster.  A factor of 10 per century
>may be decimating our population in more ways than one, and may inadvertantly
>lead to the disaster we are trying to avoid.

To be sure we need continued research of many kinds, but we do not have
the luxury of waiting for perfect understanding, either. We know what 
direction we need to head in. If we cannot achieve a birth rate of one
child per couple soon in the world as a whole, at least we can try to
achieve it in the developed world, and replacement fertility in the
developing world. The *immediate* problem before us is to minimize the
coming peak and its impacts. The longer range goals of reducing population
to under a billion and restoring large areas of ecosystem, while we
certainly ought to be thinking about them now, aren't in fact the top
items on the agenda just at present: the first order of business is
damage control. But damage control is worthless if it is undone by later
population growth, so we have begin reducing that now as best we can.

Dan M wrote:

>Even with such an attrition rate, wouldn't most of the extinction
>crisis happen in the next couple of generations anyway?

As far as species with small ranges are concerned, their extinctions
are fairly immediate as their habitats are destroyed. But for many other
species, extinction would not be so quick. Actions taken in the next few
generations, and the exact size of the peak human population, could make 
a huge difference in the final magnitude of the extinction crisis -- it 
could make the difference between a < 30% loss or a 50% loss or even 
worse. Also, decreasing birth rate is *not* the only action needed,
even within the next two generations. We also need to shift to less 
destructive subsistence patterns as quickly as possible, and this is
less a matter of population policy than of international finance and
land reform. And I amd not only speaking of tropical countries here:
the logging situation in the Pacific Northwest is also a situation
which calls for land reform of a sort: that ecosystem does not belong
to Georgia Pacific et. al. 

>>An equilibrium culture must 
>>be at equilibrium by choice, or it will not remain at equilibrium: equilibrium
>>cannot be imposed for long by an elite. Hence my constant emphasis on the
>>importance of changing values.
>
>"Changing values" means convincing people to want something other than
>what they obviously want now. This takes time; meanwhile, the 
>extinction crisis rolls on, and the longer we wait, the longer attrition
>will take to make any headway on the population problem. In short, Alan,
>you almost seem to be backpedaling here. It seems to me that decisive
>action of some sort, and soon, will be necessary make much of a 
>difference.

Yes, but the "decisive action" needed in the very near future is not a 
precipitate reduction in population -- it is a precipitate reduction in 
the impacts of population in the most vulnerable areas. But at the same 
time, we must begin to reduce population growth and aim for a level at 
which, ultimately, we will be able to return a significant fraction of 
each ecosystem to the operation of natural selection if the extinction 
crisis is to end. We need a combination of crisis management efforts to 
reduce the extinction rate where it is highest, longer-term (1-2 century) 
crisis managment of reducing the cause of the high extinction rates, and 
still longer term ecosystem restoration to actually end it.

Dan Mocsny seems to argue that if we cannot end the extinction crisis
instantly there is no point in ending it gradually; however the problem
is quantitative. A world with 80% of current biodiversity would be utterly
different from one with 20%. In the former world, humans might still live
tolerably well in reasonable numbers, in that later humans might well
rapidly become extinct. The degree of loss is everything. The integrated
area under the function defined by the human population peak times the 
impact per person defines a quantity we might think of as the total 
"human shock" to the biosphere, and the larger that quantity is, the 
greater will be the total loss of biodiversity in the current mass 
extinction event. 

There is probably no way at all that the loss could be kept below 10%
or 15% at this point. But it may still be possible to keep it under
25% or 30%. 

>>Personally, I like this scheme [birth licensingt] too. But I would happily 
>>give Alan the
>>job of enforcing it. What will you do, Alan, with (say) a poor woman 
>>on welfare who continues to bear unlicensed children? If you think you
>>are going to arrest this woman and forcibly sterilize her, well, all
>>I can say is that robots are more likely to take over the world.

Perhaps great inequalities of wealth are not ecologically wise? If there
were, e.g. a cap on income (and wealth) at perhaps 10 times the minimum
income, and the minumum income were guaranteed, along with good eductional
opportunities, then most people might have enough disposable income to be
able to choose to have two children, rather than one, if they want a second
child badly enough to give up some comfort? Remember that it isn't necessary 
to rule out all "cheaters", just as it isn't necessary to rule out all 
robbers in order for property to be possible: if most people do not cheat, 
then we can handle the few who do. Again, this is a question of values. 
If everyone is determined to cheat, or rob, the laws cannot be enforced. 
They can only work if most people support them. 

Solving the ecological crisis is probably impossible unless social
and economic justice are also ensured. Only in such a world would
people be fundamentally free enough, and educated enough, to be 
able to make the choices that will ensure the health of the biosphere.

----------
Alan McGowen

"If we breed like rabbits, in the end we shall die like rabbits."
--Rachel Carson
Newsgroups: sci.environment