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Chapter 14: Resources
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Why are resources being depleted?
Two kinds of natural resources are especially valuable to humans Minerals Energy resources We depend on abundant, low-cost energy and minerals to run our industries, transport ourselves, and keep our homes comfortable Problem MDCs want to preserve current standards of living while LDCs are struggling to attain a better standard
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Energy Resources Historically people have relied primarily on power supplied by themselves or by animals Called animate power Energy from flowing water and burning biomass fuel supplemented animate power Biomass = Wood, plant material, and animal waste During the Industrial Revolution, MDCs converted to inanimate power Generated from machines
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Energy Resources MDCs consume 3x the amount of energy that LDCs do
North Americans are the heaviest per capita consumers of energy Use ¼ world’s energy Have 1/12 world’s population Three substances provide 5/6ths of the world’s energy Coal Petroleum Natural gas All three are fossil fuels Residue of plants and animals that were buried millions of years ago Two causes for concern Supply is finite Distributed unevenly
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Fossil Fuels Renewable energy Non-renewable energy Proven Reserves
Essentially unlimited supply and is not depleted Hydroelectric, geothermal, fusion, wind, and solar energy Non-renewable energy Forms so slowly that it cannot be renewed Fossil fuels Proven Reserves Amount of energy remaining in deposits of fossil fuels Potential Reserves Energy in deposits that are undiscovered but thought to exist Undiscovered oil fields Enhanced recovery from current fields Unconventional resources Shale, oil sands
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Uneven Distribution of Fossil Fuels
Two important inequalities in global distribution of fossil fuels Some regions have abundant sources, others do not The heaviest consumers are in different regions that most of the reserves Leads to global instability Uneven distribution Coal China- 39% U.S.- 16% Petroleum Southwest Asia- 40% Central Asia- 15% Natural gas Russia- 25% Consumption U.S. imports more than ½ of their petroleum Japan 90% LDC’s quickly “catching up”
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Control of World Petroleum
Most intense conflict over energy will be centered on supply of petroleum OPEC At 1st western countries set oil prices and paid southwest Asian countries a small % of oil profits Government policies changed in 1970s in SW Asian countries Several LDC countries containing petroleum resources created OPEC in 1960 OPEC was angry at North America and Europe for supporting Israel (1970s) Led to embargo Lifted in 1974, but raised prices Caused severe economic problems in MDCs LDCS hurt even more! Changing Supply and Demand The price of oil settled by 1980s, 1990s U.S. reduced its dependency on foreign imports
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Mineral Resources Earth has 92 elements BUT 99% of the crust contains just 8 elements Oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium 8 most common combine with rare ones to create 3,000 different minerals Each mineral is a potential resource Minerals are either Metallic Have properties that are valuable for machinery, vehicles, industry Non-metallic 90% are building stones Also used for fertilizer Examples Phosphorus, Potassium, Calcium, Sulfur Mineral deposits are not distributed evenly Australia and China rank has two leading producers
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Key Issue #2- Why Are Resources Being Polluted?
Pollution occurs when more waste is added than a resource can accommodate Types of pollution: Air Water Land
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Air Pollution Definition:
Concentration of trace substances at a greater level than occurs in average air Earth’s atmosphere (at ground level) is 78% Nitrogen, 21% Oxygen, 1% Argon Most common human activities that cause pollution Motor vehicles, industry, and power plants Most common air pollutants Carbon monoxide, Sulfur dioxide Air pollution concerns geographers at three levels Global Regional local
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Air Pollution Global Regional Local Global warming Greenhouse effect
Pollution may be causing Earth’s temperature to rise Greenhouse effect Anticipated temp increase on Earth caused by carbon dioxide trapping some of the radiation emitted by the surface Can have devastating consequences, even if only a few degrees Global-scale ozone damage Stratosphere contains ozone gases Absorbs dangerous UV rays Threatened by pollutants called chlorofluorocarbons (CFCs) Regional At regional scale, air pollution may damage vegetation and water supply through acid deposition Definition: tiny droplets of sulfuric acid and nitric acid form and return to Earth’s surface Leads to acid precipitation Local Urban air pollution Carbon monoxide Hydrocarbons particulates
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Water Pollution American’s consume 5,300 liters (1,400 gallons) of water per day Water Pollution Sources Water-using industries Municipal sewage Agriculture Impact on Aquatic Life Pollution reduces Oxygen level Wastewater and Disease Most MDC’s have passed Clean Water laws Major impact Ex. Thames River- London, England LDCs have less capacity to treat wastewater Sewage flows into rivers Leads to high rates of diseases such as Cholera, Typhoid, and Dysentery
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Land Pollution Solid-Waste Disposal Hazardous Waste
The sanitary landfill is most common strategy for disposal of waste in the United States More than ½ of waste disposed this way Number of landfills has declined since 1990s Better compaction methods Recycling and incineration have also increased Can lead to air pollution Hazardous Waste Disposing is difficult Includes heavy metals , PCB oils, cyanides, solvents, acids, and caustics Can leach into soil, poisonous Must report to EPA Placed in containers and buried
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Renewing Resources Nuclear Energy Nuclear Fusion
Not renewable but seen as alternative Advantage Small amount of material releases large amount of energy Supplies 1/6th world’s energy Mostly in MDCs Problems Accidents Radioactive waste Material for nucs Limited uranium supply Cost/ distribution Nuclear Fusion Some nuclear power issues could be addressed by fusion Definition: Fusing of hydrogen atoms to helium Can only occur at high temps
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Leading Renewable Energy Sources
Biomass More than ½ of renewable energy Wood is a renewable resource Crops such as corn, sugarcane, and soybeans can be used for energy Limited use Energy to grow crops = to output Forest reduced Serves other purposes already such a food, clothing, shelter Hydroelectric Power Use of moving water to create energy Has been used throughout history 2nd most popular source of electricity Can be environmental disaster China – Three Gorges Dam Wind Power Historical source of power Benefits Less change to environment Greater potential for increased use Problems Noisy Lethal to birds Visual blight Geothermal Energy Energy from hot water or steam Prominent in volcanic areas Lots of research currently underway
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Solar Energy The ultimate renewable source is solar energy
Currently supply 1% of electricity to U.S. Potential is limitless Sun’s estimated life = 5 billion years Sun’s energy is free, can’t be owned, bought, or sold Does not damage the environment or cause pollution Active solar energy Collect solar energy and convert it either to heat energy or to electricity Example: Solar panels Passive solar energy Capture of solar energy without any devices South-facing windows greenhouses
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Renewable Energy in Motor Vehicles
Most serious challenge to reducing dependence on non-renewable energy is the motor vehicle Batteries Battery-powered, electric cars popular in 1900s Shortcomings Limited range Costs more to operate Recharging can take several hours Led to creation of hybrids Biofuels Ethanol can be produced from biomass (corn in U.S., sugarcane in Brazil) Takes a lot of energy, is source of food Hydrogen fuel cells Convert hydrogen and oxygen into water, producing electricity and heat in the process Can be used to power motors or electrical devices Obtaining hydrogen a problem Have to separate it Hydrogen fuel used to lift shuttles into orbit, power shuttle’s electrical systems For motor vehicle use would require a new distribution system
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Recycling Definition:
The separation, collection, processing, marketing, and reuse of the unwanted material Increased in U.S. from 1970 from 7% to 33% in 2007 Main items recycled Paper, plastic, glass, aluminum
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Sustainable Development
Definition: Development that meets the needs of the present without compromising the ability of future generations to meet their own needs Conservation definition: Sustainable use and management of natural resources such as wildlife, water, air, and Earth’s resources to meet human’s needs Preservation Definition: Maintenance of resources in their present condition Sustainability Difficult to balance environment with concern for economic growth Example: China Has 16 of 20 most polluted cities in the world
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