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U.S. raw materials put into use each year, 1900–2014 (materials in imported goods excluded). USGS.
A growing industrial economy needs raw materials — for construction (buildings, bridges, highways), defense, and making goods and services. This USGS fact sheet tallies, by weight, the raw materials other than food and fuel used in the U.S. economy each year for 115 years, from 1900 through 2014, updating a 2012 fact sheet that ended in 2010.
Why weight
Counting materials by weight rather than dollars shows their physical footprint. Some bulky materials, like crushed stone, are benign; small amounts of others — arsenic, cadmium, mercury — can be toxic. Extracting and using raw materials can harm the environment and society if not managed carefully, and the long shift from renewable to nonrenewable materials shows how dependent the country has become on them to sustain its standard of living.
How "use" is measured: annual apparent consumption — domestic production plus imports plus recycling, minus exports — of raw materials ready for use at home or in making products used at home or exported. Materials inside imported finished goods are left out, because tracking them is hard in such a large trading economy.
A century of booms and busts
Short- and medium-term swings track big events: World War I, the Great Depression, World War II and the postwar boom, the 1970s oil crises, the recessions of the 1980s and early 1990s, the late-century boom, and the great recession of 2007–2009. By 2014 use still hadn't regained pre-recession levels — except recycled metals, which kept rising.
The four categories
| Category | What it includes | Trends |
|---|---|---|
| Agriculture | nonfood plant, animal and fish products — cotton, flaxseed, tobacco, natural rubber, wool, leather, fish meal | small by weight; down to about 40 percent of its 1993 level by 2014, as synthetics and imported products replaced them |
| Forestry | nonfuel wood and paper, including recycled paper | lumber was the main building material early on; wood use hit a low of 27.5 million metric tons in 1932 and kept falling as cement and steel took over; since 1990, paper and paperboard have outweighed wood. In 2014 about 63 percent of paper and paperboard was recovered for recycling |
| Nonfuel minerals | construction materials, industrial minerals, metals | by far the largest share (below) |
| Nonrenewable organics | nonfuel products of petroleum, natural gas and coal — asphalt, road oil, plastics feedstocks, lubricants, synthetic fibers and rubber, waxes | 1.59 Mt in 1900, growing to 155 Mt in 1999, then about 123 Mt in 2014 after the recession; synthetics displaced wood, metals and minerals |
Nonfuel minerals
- Construction materials: crushed stone and construction sand and gravel made up 72 percent by weight of new mineral materials used in 2014 — driven over the century by infrastructure such as the Interstate Highway System, roads, airports, dams, buildings and housing. Use in 2014 remained well below the 2006 peak but was expected to rise.
- Industrial minerals: 13 percent of materials used in 2014 — barite for drilling, fertilizer minerals (nitrogen, phosphate rock, potash), fluorspar, lime for steelmaking, salt, and more.
- Metals: from aluminum to zinc, including specialty metals like indium, gallium and lithium. In 2014 recycled metals were about 40 percent of metals use by weight, and metals use had recovered from the recession.
- Small but vital: materials like silicon (semiconductors, solar), titanium (aerospace) and indium (flat-panel displays) weigh little but are extremely valuable in a computerized society.
Recycled asphalt: in 2014 more than 71.9 Mt of reclaimed asphalt pavement and nearly 2 Mt of recycled asphalt shingles went into new pavements — not counted in the study, but possibly part of why nonrenewable organics declined.
From renewable to nonrenewable
Renewable resources — agriculture, fishery, forestry and wildlife products — regrow unless overharvested; nonrenewable ones — nonfuel minerals and nonrenewable organics — come from geologic deposits. In 2014, only 4 percent of the nearly 3,000 Mt of new materials entering the economy were renewable, down from 46 percent in 1900. More than half of all the materials used in the study period were used in the last 30 years.
Renewable and nonrenewable shares of U.S. material use, 1900–2014. USGS.
Balancing extraction, use and environmental effects could affect industrial supply chains, but better substitutes, better discovery and extraction technology and more efficient recycling may keep nonrenewable supplies from running out and secure a sustainable supply.
Sources
Based on Use of Raw Materials in the United States from 1900 through 2014, by Grecia R. Matos, USGS Fact Sheet 2017–3062, U.S. Geological Survey (DOI), drawing on data from the U.S. Bureau of Mines, USGS, USDA, NOAA, the Census Bureau, the Energy Information Administration, the U.S. Forest Service, the U.S. International Trade Commission, the Food and Agriculture Organization and Resources for the Future, and citing Matos and Wagner (1998), Wagner (2002), Tepordei (1997) and the National Asphalt Pavement Association (2015); a work of the United States government in the public domain. The graphs and the end of the asphalt passage come from the fact sheet's PDF.
Licenza: CC0 1.0 (pubblico dominio) · Tratto da pubs.usgs.gov
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