10.2limited reserves -dilmma of stock resource

人口數增加world population doubled between 1800 and 1930, 1930 and 1975
生活水準提升living standards rise(resource consumption per capita)combine two the level of resource extraction between 1880 and 2000 is sextupling.
food, energy, iron alloys鐵合金, lumber

非再生性資源的有限性
optimistic view
long-term trends in fluctuations in price level for natural resource. do not appear become significantly scarcer since 1870
what happen when a rapid hike occurs in the price of a commodity? ( tin-1960s, oil-1974)
1.greater care in use.
2.substitued for one another.
3.switch in methods of extraction, switch to lower-grade resource.

pessimistic view
consumption of resource is partly a function of the rate of population growth and the rates of energy consumption per capita.a primitive person around 1000watts per capita and now around 10000 watts per capita.

half the oil consumption since the 1950s,half the coal consumption since the 1930s,100 million years to form will be consumed in about 100 years of industrialization.
能源資源枯竭
80% the petroleum resource will probably exhausted in about a century.
80% the coal reserves will be depleted in about 300 to 400 years.
the age of fossil fuels will be a limited one, from AD1500 to AD2800.

石油供給的空間改變rapid geographic change in aeras of supply
1880s,1890s-Caucasus in southern Russia and Dutch Indonesia
1900s-Texas and Oklahoma
1930s-Venezuela and Middle East
1960s-Libya and Algeria
1970s-Nigeria, the North Slope of Alaska, Europe's North Sea
1990s-coast of north Australia and south China
3/4 world oil reserves are in Persian Gulf.
OPEC石油輸出國家組織-會員國與石油日產量

替代能源alternative energy sources
替代石油(35-84年)的能源主要為煤(225-900年)與天然氣(125-200年)
solar radiation, wind power, tidal energy, geothermal energy, atomic fission, and atomic fusion.
具有商業性的再生能源:生質能.水力.地熱
table 10.3 potential of alternative energy resource