The 14.3 percent
surge in production was driven not only by common metals such as
aluminum, arsenic, cadmium, chromium, copper, gold, lead, mercury,
nickel, and steel, but also by more obscure but emerging metals. "Dozens
of metals show strong growth as more countries industrialize," says
report author Gary Gardner, a senior fellow at Worldwatch. "And
increasingly complex products require materials that are not heard about
in daily conversation----from hafnium used in nuclear reactors to rhenium, a key metal in jet engines."
The surge in metals
production in the past decade is spurred by robust economic output in
advanced developing countries, according to the report. "While steel
production declined sharply in advanced industrial regions during the
2007-09 recession, it continued its longtime increase in Asia, driven in
particular by ongoing strong growth in China," says Gardner. "Steel
production in China has quadrupled in the past decade."
Not surprisingly, per
capita metal consumption is closely correlated with per capita gross
domestic product (GDP). According to the U.S. Geological Survey,
countries with per capita GDPs of under $5,000 consume less than 5
kilograms of aluminum per person, whereas those with GDPs exceeding
$25,000 consume 15 to 35 kilograms per person. Wealthier countries also
have greater levels of stocks in use----in buildings, vehicles, and myriad other economic outputs----than developing countries, often by a factor of 3 to 10, writes Gardner.
"Metals, of course,
are a non-renewable resource," notes Worldwatch President Robert
Engelman. "A rise in production that matches economic growth is a key
indicator of the global economy's unsustainability. Ultimately, recovery
and recycling will have to dominate metals supply, because mining and
production cannot do so indefinitely."
Given the combination
of longstanding metals demand in industrialized countries and surging
demand in developing countries, conservation policies will be needed as
some metals approach the limits of available supply. Researchers
conclude that a potential future global population of 10 billion people
could consume 1.7 trillion kilograms of copper total, greater than the
estimated global in-ground stocks of 1.6 trillion kilograms.
Progress on metals
conservation is slow, however. According to the United Nations
Environment Programme's International Resource Panel, the share of
discarded metal that is recycled----known as the "end-of-life recycling rate"----is
above 50 percent for only 18 of 60 metals surveyed. "Higher recycling
rates tend to be associated with materials that are used in large
amounts in easily recoverable applications, such as car manufacturing,"
says Gardner. "Metals with lower rates of recovery are often used in
small quantities in complex products, such as electronics."
Many of the metals
produced and consumed worldwide end up in landfills, making recovery
difficult. Stocks of aluminum in U.S. landfills are equivalent to 43
percent of the aluminum in use in the U.S. economy. And landfill stocks
of steel amount to about 20 percent of all steel in use in the United
States. "Recovery of these landfill-based resources is not yet
economically feasible, but it might be one day," says Gardner.
The pattern of metal
use varies between developing and industrialized countries. Developing
countries generate less aluminum scrap from recycling in the early
decades of development than in the mature stages of their economic
growth.
Future policy
decisions will need to support the creation of a circular economy that
reuses and recycles materials and that remanufactures products to the
extent possible. Germany, Japan, and China are countries already making a
circular economy a priority.
Further highlights from the report:
- Global extraction growth rates for copper,
zinc, nickel, tin, and platinum averaged 3.4 percent annually over the
past few decades, which implies a doubling of extracted material volumes
every 20 years.
- By one estimate, 97.5 percent of all copper produced worldwide in the last 1,000 years has been produced since 1900.
- China ranks in the top five producers globally for 8 of the 10 most common metals.
- The U.S. Geological Survey estimates that U.S. landfills hold enough steel to build 11,000 Golden Gate Bridges.
- Most
of the projected 2.7-fold increase in world aluminum consumption
between 2006 and 2025 is expected to come from developing countries.
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