Yale Study: Not Enough Metals In Earth To Meet Global
Demand
by Staff Writers
New Haven CT (SPX) Jan 27, 2006
Researchers studying supplies of copper, zinc and other metals have
determined that these finite resources, even if recycled, may not
meet the needs of the global population forever, according to a
study published in the Proceedings of the National Academy of
Sciences.
According to the study, even the full extraction of metals from the
Earth's crust and extensive recycling programs may not meet future
demand if all nations begin to use the same services enjoyed in
developed nations.
The researchers Robert Gordon and Thomas Graedel of Yale
University and Marlen Bertram of the Organisation of European
Aluminum Refiners suggest that the environmental and social
consequences of metals depletion became clear from studies of metal
stocks--in the Earth, in use by people and lost in
landfills--instead of tracking the flow of metal through the
economy in a given time and region.
"There is a direct relation between requisite stock, standard of
living and technology in use at a given time," said Gordon,
professor of geology and geophysics. "We offer a different approach
to studying use of finite resources--one that is more directly
related to environmental concerns than are the discussions found in
the economics literature."
Using copper stocks in North America as a starting point, the
researchers tracked the evolution of copper mining, use and loss
during the 20th century. Then the researchers applied their
findings and additional data to an estimate of global demand for
copper and other metals if all nations were fully developed and
used modern technologies.
According to the study, titled "Metal Stocks and Sustainability,"
all of the copper in ore, plus all of the copper currently in use,
would be required to bring the world to the level of the developed
nations for power transmission, construction and other services and
products that depend on copper.
For the entire globe, the researchers estimate that 26 percent of
extractable copper in the Earth's crust is now lost in non-recycled
wastes; for zinc, it is 19 percent. Current prices do not reflect
those losses because supplies are still large enough to meet
demand, and new methods have helped mines produce material more
efficiently.
The study suggests these metals are not at risk of depletion in the
immediate future. However, the researchers believe scarce metals,
such as platinum, risk depletion in this century because there is
no suitable substitute for use in devices such as catalytic
converters and hydrogen fuel cells. They also found that, for many
metals, the average rate of use per person continues to rise. As a
result, the report says, even the more plentiful metals may face
similar depletion risks in the future.
"This is looking at recycling on a broader scale," said Cynthia
Ekstein, the National Science Foundation (NSF) officer who oversees
the Yale award. "This is looking at the metal lifecycle from cradle
to grave."