Keith said,
For stability (and, for goodness sake, a sufficient retention of sufficient natural wildernesses in the world) we could do with a population at least half of what we have now. And Cordell asks, Which half should we do without? -----Original Message----- From: Keith Hudson [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 12, 2001 7:37 AM To: Harry Pollard Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: RE: not so fast! Hi Harry, I buy a great deal of what you've written in reply to Lawrence. Many of the so-called limits to growth (economic and population) which started to be advanced in the 1960s and 70s have turned out to be chimerical. However, there are a couple of factors concerning population which I don't think can be glossed over -- one current and the other a potential one. The current one concerns water shortage. There is little doubt that in many parts of the world there is a fresh water shortage already. Because of extraction along their routes, many rivers are largely devoid of water by the time they reach the sea. Those who are more expert than me in these matters seriously suggest that water shortages will be a major cause of wars in the not-too-distant future. The one example I can think of at the moment is the Euphrates -- from which Turkey, Syria and Iraq are all extracting increasing amounts. Turkey is building dams and irigation systems and I can only think that some sort of nasty response will be called forth at some point. The other concerns the production of nitrogenous fertiliser. This is derived from fossil fuels as chemical feedstock in pretty easy and direct fashion and is thus relatively cheap. But even now, most of the agricultural regions of the world can't afford to buy as much as is needed in order to grow sufficient food, never mind when developing countries start to demand more meat which needs an extra stage of production and imposes a 10-fold decrease in efficiency in protein production. As fossil fuels decline in the coming years (and just think for a moment what the demands of China will be in the coming years as the country industrialises!) then fertiliser will become enormously expensive -- even in the developed world. Those who say that in a post-fossil fuel world it could be manufactured via electricity from nuclear, wind or solar power don't realise that subsequent hydrolysis of water into hydrogen, and the successive stages of production to produce fertiliser, each with low efficiency, means that nitrogenous fertiliser would be anything between 20 and 50 times more expensive than now. For stability (and, for goodness sake, a sufficient retention of sufficient natural wildernesses in the world) we could do with a population at least half of what we have now. Keith ___________________________________________________________________ Keith Hudson, Bath, England; e-mail: [EMAIL PROTECTED] ___________________________________________________________________
