Resources and the Environment NNatural resource- is found in nature and can be used by humans RRenewable resources – can be replenished within a lifetime EEx. water, wind, solar, geothermal NNonrenewable resources - form over millions of years  Ex. nuclear power and fossil fuels (coal, natural gas, oil) SSun is the ultimate source of most energy on Earth. – The Sun’s energy is transferred from photosynthetic organisms to all other living things.

Traditional Sources of Energy Biomass- material from living or recently living organisms Wood Field crops Dried fecal material Peat These are all renewable sources

Energy Resources Worldwide Industrialized countries- 90% nonrenewable sources (petroleum, coal, natural gas, nuclear) 10% renewable sources (biomass, water, solar, wind, geothermal) Developing countries- 59% nonrenewable sources 41% renewable sources

2004 Worldwide Energy Sources graph

Global energy usage in successively increasing detail (2005)

Nonrenewable Energy Sources- Fossil Fuels Fossil Fuels- coal, oil, natural gas  Fossil fuels, such as natural gas, coal, and petroleum, are non-renewable resources formed from organisms that lived millions of years ago. Pros:  Can be used for both vehicles and electricity generation  Efficient energy source Cons:  Burning of fossil fuels releases sulfur and nitrogen oxides into the atmosphere; creates air pollution.  Burning produces carbon dioxide and water vapor (greenhouse gases) which may contribute to global climate change.

Another Nonrenewable Energy Source- Nuclear Energy Nuclear energy involves the fission of U235

Nuclear Power Pros and Cons Pros: Does not release greenhouse gases Does not contribute to acid rain Very efficient energy source Cons: Safety concerns (accidents, terrorist strikes) Radioactive waste

Alternative Energy Resources These are all renewable Solar Water (Hydroelectric) Wind Geothermal Biomass Look over pros and cons for each in the table on page 184 of your Resources handout

Land Resources Soil Fossil fuels- formed from ancient remains of plants and animals Ore- a mineral or rock that can be mined for profit

Human Impact on Land Resources Agriculture may lead to a loss of topsoil and also involves fertilizers and pesticides Urbanization involves loss of ecosystems due to construction of cities Deforestation occurs when trees are removed and not replanted; –L–Leads to topsoil erosion –A–Also changes the carbon cycle

Carbon “sinks” and “sources”

Human Impact on Air Resources Air is 78% nitrogen, 21% oxygen and less than 1% water vapor, carbon dioxide, argon Burning fuel (wood, coal, etc.) produces particulate matter (small particles) that may damage lung tissue Burning of fossil fuels release greenhouse gases (such as water vapor; CO 2, methane) Burning fossil fuels also releases sulfur dioxides and nitrous oxides which contribute to acid rain

The Greenhouse Effect Short wavelength radiation from sun passes through the atmosphere and warms Earth Long wavelength (infrared)energy is trapped by greenhouse gases (H 2 O; CO 2, methane, nitrous oxide, ozone) and keeps Earth consistently warm Increased GH gases can lead to increased temps on Earth (now that’s global warming)

Greenhouse Effect The greenhouse effect results from the trapping of radiation by gases in the atmosphere (H 2 O; CO 2, methane, nitrous oxide, ozone are major greenhouse gases) -this is a natural process, but humans are adding increased levels of greenhouse gases to the atmosphere by burning fossil fuels

Global Warming Many sci believe increased levels of greenhouse gases are leading to global warming (gradual increase in Earth’s temp)

Climate change info… Earth’s average surface temp has increased about 1°F in last century According to NOAA: 7 of the 8 warmest years on record have occurred since 2001 and the 10 warmest years have all occurred since 1995.

Natural v. Human Causes of Global Warming Greenhouses gases (like CO 2, H 2 O) heat Earth’s atmosphere and cause global warming – Natural sources of CO 2 gas- volcanic eruptions, decay of organic (plant, animal) matter, cell respiration, etc. – Human sources- burning of fossil fuels for transportation, heating, energy production

Greenhouse Gases continued…. Each greenhouse gas differs in its ability to absorb heat in the atmosphere. – Carbon dioxide (CO 2 ) – 1 – Methane (CH 4 ) - 21 times CO 2 – Nitrous oxide ‐ 310 times CO 2 – HFCs ‐ 1,300 to 6,500 times CO 2 These numbers convert everything into carbon dioxide equivalents

Why does burning fuel create greenhouse gases? Remember the equation for combustion? Fuel + oxygen  carbon dioxide + water + energy – Combustion causes almost every atom of carbon in the fuel to combine with 2 atoms of oxygen -1 gallon of gasoline yields about 19 pounds of carbon dioxide (plus water vapor, and soot) when burned. Add to that the 6 pounds of CO 2 needed in the manufacturing and transportation of the fuel, for a total of 25 pounds of carbon dioxide

From the Counting Carbons article 1 gallon of gasoline  25 pounds CO 2 1 kilowatt‐hour of electricity  1.64 pounds of CO 2 1 cubic foot of natural gas  0.12 pounds of CO 2 1 gallon of heating oil  pounds of CO 2

Ozone (O 3 ) “Good” ozone occurs naturally in the Stratosphere (upper atmosphere) -absorbs harmful UV radiation from sun “Bad” ozone occurs in the troposphere (near the ground) as a result of pollution (sunlight breaks up NO x, CO, other hydrocarbons); makes up smog

weplanet/poles/antarc ti/ozone.html

CFCs- Chlorofluorocarbons Used in aerosol cans,fridges; ACs; cleaning electronic parts Montreal Protocol banned the use of CFCs (1987) UV radiation breaks down CFCs and the chlorine destroys “good” ozone

Montreal Protocol 1987 International treaty designed to protect the ozone layer Called for the phasing out of production and use of CFCs and HCFCs (responsible for ozone depletion)

Kyoto Protocol 1997 Set targets for 37 industrialized countries and the European community for reducing greenhouse gas emissions Reductions amount to an average of five per cent (against 1990 levels) over the five-year period

Water Resources 97% of water on Earth is salt water 3% is freshwater, but less than 1% is potable (drinkable) Why? Water shortages occur mostly in Africa and Middle East; we see shortages in the U.S. in western states (CO, AZ, CA)

Water Cycle

Human Impact on Water Point pollution- from a single location (ex. sewage treatment plant, factory) Nonpoint pollution- from many locations (acid rain, runoff, fertilizers, manure)

Some Major Water Pollutants PollutantSource NitratesFertilizers, wastes PhosphatesFertilizers, detergents Metals (Mercury, Lead)Industry, fuels, acid rain drainage Oil, gasolinefuels

Sustainable Energy Policy that will meet energy needs without causing harm to the planet –I–Involves energy efficiency and renewable energy Only possible if many countries work together and are committed to this