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Re: Yuri receives hypocrite of the week award (was Re: Ecological Economics and Entropy)
I was too brief on the question of fresh water supplies limiting
population. Here are some points.
1. The U.S. and much of the world have excess agricultural production
capacity. Consequently, there is fierce price competition. Every
significant cost advantage is important.
2. Where irrigation is required, the price paid for water often
determines whether agriculture there can compete, and this has been
true for many decades. In many places farmers managed to get water at
prices that depended on allocating much of the costs of dams, etc. to
other benefits, e.g. flood control, electric power and recreation.
Because the environmentalists now have comparable political power to
farmers and boaters, making a large lake out of a valley now is
regarded as a negative benefit in the politicla process.
3. When we discuss the extent to which fresh water limits population,
different economic realities prevail. The world can afford to pay
much more for fresh water than it does, i.e. paying much more for
agricultural water would not raise the cost of food very much. (I
would like to have numbers here, but I would bet that only a small
fraction of the 16 percent of American personal income spent on food
represents the cost of water.) Enormous water projects, e.g. the 1964
proposal for the North American Water Alliance, will be affordable if
growing enough food requires them. Desalination of sea water will be
affordable on a large scale.
4. Finally, it is possible to economize enormously on agricultural
water where this pays. For example, hydroponic tomatoes require 1/30
the water required by field grown tomatoes. That this advantage in
water use has not caused hydroponic tomatoes to dominate the market is
evidence for the present low cost of water.
Finally, it seems to me that the projections of water shortage
limiting population are based on the acceptance of some constraints on
ways of increasing water supply that are operative only in the present
economic and political situation.
See my http://www-formal.stanford.edu/jmc/progress/water.html for more
detail.
--
John McCarthy, Computer Science Department, Stanford, CA 94305
http://www-formal.stanford.edu/jmc/progress/
During the last years of the Second Millenium, the Earthmen complained
a lot.
References: