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Chapter 14: Resources 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 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 Energy Resources MDCs consume 3x the amount of energy that LDCs do North Americans are the heaviest per capita consumers of energy 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 – Use ¼ world’s energy – Have 1/12 world’s population Two causes for concern – Supply is finite – Distributed unevenly Fossil Fuels Renewable energy – 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 Uneven Distribution of Fossil Fuels Two important inequalities in global distribution of fossil fuels – Coal – 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 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” Control of World Petroleum Most intense conflict over energy will be centered on supply of petroleum OPEC – OPEC was angry at North America and Europe for supporting Israel (1970s) – 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 – Caused severe economic problems in MDCs – LDCS hurt even more! Led to embargo Lifted in 1974, but raised prices Changing Supply and Demand – The price of oil settled by 1980s, 1990s – U.S. reduced its dependency on foreign imports Mineral Resources Earth has 92 elements BUT 99% of the crust contains just 8 elements Minerals are either – Metallic – Oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium – Non-metallic 8 most common combine with rare ones to create 3,000 different minerals Each mineral is a potential resource Have properties that are valuable for machinery, vehicles, industry 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 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 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 Air Pollution Global – Global warming – At regional scale, air pollution may damage vegetation and water supply through acid deposition 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 Regional Definition: tiny droplets of sulfuric acid and nitric acid form and return to Earth’s surface Leads to acid precipitation Local – Urban air pollution – Absorbs dangerous UV rays Threatened by pollutants called chlorofluorocarbons (CFCs) Carbon monoxide Hydrocarbons particulates Water Pollution American’s consume 5,300 liters (1,400 gallons) of water per day Wastewater and Disease – Most MDC’s have passed Clean Water laws – Major impact Water Pollution Sources – Water-using industries – Municipal sewage – Agriculture Impact on Aquatic Life – Pollution reduces Oxygen level 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 Land Pollution Solid-Waste Disposal – 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 Renewing Resources Nuclear Energy – 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 Leading Renewable Energy Sources Biomass – More than ½ of renewable energy – Historical source of power – Benefits Wood is a renewable resource Crops such as corn, sugarcane, and soybeans can be used for energy – Limited use – 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 Less change to environment Greater potential for increased use – Problems Energy to grow crops = to output Forest reduced Serves other purposes already such a food, clothing, shelter Hydroelectric Power Wind Power Noisy Lethal to birds Visual blight Geothermal Energy – Energy from hot water or steam – Prominent in volcanic areas – Lots of research currently underway Solar Energy The ultimate renewable source is solar energy – Collect solar energy and convert it either to heat energy or to electricity – Currently supply 1% of electricity to U.S. Active solar energy Potential is limitless – Solar panels – 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 Example: Passive solar energy – Capture of solar energy without any devices Example: – South-facing windows – greenhouses Renewable Energy in Motor Vehicles Most serious challenge to reducing dependence on nonrenewable 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 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 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