The Latest Malthusian Scare …
… is about the impending metal shortage. For example:
There are about 150 kilograms of copper in current use for each person in North America. The researchers then multiplied the copper used per person by total world population, using standard population estimates to project into the future. By the mid-21st century, if everyone in the world used copper at North American rates, every scrap of known copper ore would be mined, the team reports online this week in Proceedings of the National Academy of Sciences.On the other hand, according to The Challenge of Man's Future by Harrison Brown (written back in the days when Malthusians tried looking at all the data):
Eventually the time will come when ordinary rocks such as granite will be looked upon as ores. We have already seen that average granite contains sufficient uranium and thorium to pay, energy-wise, for the processing of the rock and still leave a substantial energy profit. In addition, without unduly increasing the energy expenditure, one can probably extract from the rock a multitude of elements that are essential to an industrial society. One hundred tons of average igneous rock contain, in addition to other useful elements, 8 tons of aluminum, 5 tons of iron, 1200 pouInds of titanium, 180 pounds of manganese, 70 pounds of chromium, 40 pounds of nickel, 30 pounds of vanadium, 20 pounds of copper, 10 pounds of tungsten and 4 pounds of lead.In other words, the copper needs for an average person in an industrial society can be met by 1500 tons of granite. That's 500 cubic meters or the top centimeter of 50,000 square meters. 50,000 square meters is the land use per person at 20,000 people per square kilometer, which is twice as dense as New York City. We have plenty of room.
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