Justin, wisely:
>>We will never live on the Great Rock Candy Mountain, where roast
>>chickens grow on trees and fish jump into our frying pans. In the
>>background there are two great facts: one is the absolute material
>>limit on certain resources--oil, coal, gas, fresh water, arable
>>land. There is just so much of that that exists or could exist.
Fortunately the findings of the Limits to Growth from which the contemporary sense of limits arises, and the dire warnings based upon them were readily disproved. In error, authors Forrester and the Meadows had taken the existing level of known resources as a constant, and simply projected the rate of consumption into the future, reaching their date of 2100 as depletion. However, reserves of mineral wealth are, perhaps surprisingly, not a constant at all. On the contrary, with the passage of time, reserves tend to increase. Until 1999, when a small decline was reported, the world's oil reserves have been tabulated as increasing every year since 1992 (Oil and Gas Journal, December 20, 1999, Vol. 97, No. 51). The reason is that reserves that were previously discounted as uneconomical to drill are re-classified as reserves when advances in productivity - or simply increases in price - bring them into reach. With new exploration and extraction techniques new reserves of mineral wealth are discovered every year.
When Limits to Growth was published, Sussex University scientist William Page pointed out the error of assuming that reserves were a known, or fixed quantity. Page referred to a 1944 review saying that had it 'been correct the Americans would by now have their reserves of about 21 of the 41 commodities examined' in the review (HSO Cole et al, Thinking About the Future, Sussex University Press, 1973, p38). Page disputed the timescale of absolute resource depletion with a simple illustration, un- tapped mineral wealth in the world's seawater:
1,000,000,000 years' supply of sodium chloride, magnesium and bromine 100,000,000 years' supply of sulphur, borax and potassium chloride 1,000,000 years supply of molybdenum, uranium, tin and cobalt 1000 years supply of nickel and copper 16 000 million tons of aluminium, iron and zinc
Furthermore, writes Page, with drilling going no further than six of the 25-40 miles of the earth's crust, reserves have not even been touched yet. Page's point is not that the resources of the Earth are infinite. Only that the Limits to Growth computer model massively understated them. He predicted then that, in principle, resources were sufficient for 'perhaps tens of thousands of years' (p37). As Page says 'the most pressing limits to growth are not geological: Mother Nature has put ample on the planet'. Rather 'what limits there may be come from man's economic and technological ability to exploit these resources' (p37).
-- James Heartfield