key issue # 1: why are resources being depleted? environment
TRANSCRIPT
KEY ISSUE # 1: WHY ARE RESOURCES BEING DEPLETED?
ENVIRONMENT
ANIMATE POWER
INANIMATE POWER
• Generated from machines• 3 of the earth substances provide 5/6 of
the world’s energy: oil, natural gas, and coal• Fossil fuels• Biomass fuel
COAL TO NATURAL GAS
• Industrial Revolution – • Petroleum was first pumped in 1859, but
was not an important resource until the diffusion of automobiles• Natural gas was originally burned off as a
waste product of oil, but now it heats millions of homes
ENERGY IS USED IN THREE PLACES
1. Businesses – U.S. businesses primarily use coal
2. Homes – heating of the living space and water is primarily done with natural gas
3. Transportation – almost all transportation systems operate on petroleum products
TWO MAJOR CONCERNS
1. Supply2. Uneven Distribution
REMAINING SUPPLY OF FOSSIL FUELS
• Proven Reserve – the amount of energy remaining in deposits that have been discovered• Potential reserve – the energy in
undiscovered deposits that are thought to exist
EXPANDING PRODUCTION
• Extracting proven reserves will grow to be more difficult
• Unconventional sources
LOCATION OF RESERVES
• Coal – forms in tropical locations, in lush, swampy areas rich in reserves• Today’s supply of coal is found in mid-latitudes
• Oil and Natural Gas – formed millions of years ago from sediments on the sea floor• Five Middle Eastern countries have 2/3 of the
world’s reserve – Saudi Arabia, Iran, Iraq, Kuwait, and U.A.E.• Venezuela and Mexico
CONSUMPTION OF FOSSIL FUELS
• PEDs, with ¼ of the world’s population, consume about ¾ of the world’s energy
• Two Geographic Consequences for the future:
1. PINGs will consume more energy in the future; world consumption will rise
2. Because PEDs consume more than they produce, they must import fossil fuels, especially petroleum, from PINGs.
* Since PINGs will need more energy, PEDs will face more competition in the future for obtaining the remaining reserves of fossil fuels
OPEC POLICIES DURING THE 1970S
• Organization of Petroleum Exporting Countries (1960)• Gas Crisis of the 1970s• Internal conflicts weakened OPEC in the
1980s and 1990s
CHANGING SUPPLY AND DEMAND
• Conservation • Low prices in the 1990s • Rise in prices in the 21st century • Petroleum will not run out during the 21st
century, but the cost of extracting it will rise, and alternative energy sources will rise
NATURAL GAS
• Cheaper to burn and less polluting than petroleum and coal
• World natural gas consumption increased 4% per year during the 1980s, and is currently increasing about 3% each year
• The two major sources of reserves1. Iran2. Russia
AIR POLLUTION
• Burning coal creates several pollutants: sulfur oxides, hydrocarbons, carbon dioxide, and particulates (soot)• The U.S. Clean Air
Act now requires utilities to use better-quality coal or to install “scrubbers” on the smokestacks
MINE SAFETY
• Mining is an extremely dangerous occupation• Miners are also prone to “black lung”
disease• Strictly enforced mine safety laws,
improved mine ventilation, intensive safety programs, automation of mining, and a smaller workforce have made the American mining industry much safer
SUBSIDENCE AND EROSION
• Underground mining may release acidic groundwater into streams• Sinking of the ground could damage buildings• Erosion – the removal of trees in order to mine for
coal could cause erosion
ECONOMICS
• Coal must be shipped a long ways because factories tend to be a long ways from the coalfields• The principal methods of transporting coal
– barge, train, or truck, all require petroleum• A lot of energy is expended so that coal
can be used
NUCLEAR ENERGY
• The Big Advantage = the large amount of energy that is released from a small amount of material• Nuclear power supplies about 1/6 of the
electricity in the world• Europe – heavily dependent upon nuclear• In the U.S. -
POTENTIAL ACCIDENTS
• Fission• Radioactive
waste• Elaborate safety
precautions• Chernobyl (1986)
RADIOACTIVE WASTE
• Plutonium• No one has developed permanent storage
for nuclear waste• The U.S., has not found a safe place
underground because of worry about groundwater
BOMB MATERIAL
• Nuclear power has been used in warfare twice, in August 1945 when the U.S. dropped an atomic bomb on Hiroshima and then Nagasaki• The Soviet Union, United Kingdom, France,
China and India have all tested nuclear weapons
LIMITED URANIUM RESERVES
• Proven uranium reserves are limited – about 60 years• Breeder reactor – turns uranium into a
renewable resource by generating plutonium, also a nuclear fuel• Plutonium is more lethal than uranium
COST
• Nuclear power plants cost billions of dollars to build• The complexities
of safe uranium transportation add cost
EARTH’S CRUST
• 92 natural elements, but 99% of the earth’s crust is composed of eight elements – oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium• Oxygen accounts for nearly ½, and silicon
nearly ¼• The eight most common elements
combine with more rare ones to make about 3000 different minerals
MINERALS AS RESOURCES
• Each mineral is potentially a resource if people find a use for it• The definition of which minerals constitute
resources evolves as technology and economies change
DEPOSITS
• Mineral deposits are not uniformly distributed across the world• Most of the world’s supply of particular
minerals is found in a handful of countries