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The complex molecules that comprise organisms are based on carbon CB 54.17 Carbon cycle Solar energy: incoming and outgoing http://www.esr.org/outreach/climate_change/basics/basics.html http://www.esr.org/outreach/climate_change/basics/basics.html CO2 and other greenhouse gases keep heat from radiating back into space http://www.esr.org/outreach/climate_change/basics/basics.html CO2 levels in Hawaii and average global temp. CB 54.24 http://www.esr.org/outreach/climate_change/basics/basics.html http://www.esr.org/outreach/climate_change/basics/basics.html http://www.esr.org/outreach/climate_change/basics/basics.html Recent increases in global temperature have reversed a slight cooling trend Vikings in Greenland in the 12001400’s As the climate cooled, the Vikings were forced to abandon their outposts 370 Relative contributions to Global Warming ~300 m people ~500 m people ~2.5 b people Effects of global warming are already visible http://www.worldviewofglobalwarming.org/pages/glaciers. html http://blogs.sciencemag.org/newsblog/2007/02/h oldren_wants_d.html#more http://podcasts.aaas.org/science_podcast/Science Podcast_070216.mp3 Observed and projected ice cap melting http://www.esr.org/outreach/climate_change/basics/basics.html http://www.esr.org/outreach/climate_change/basics/basics.html Global Change & Human Health (2001) V 2 # 1 pg 64 Precipitation changes 1900 to 2000 Change in risk of malaria by 2080 Global Change & Human Health (2001) V 2 # 1 pg 64 http://www.sciencemag.org/cgi/content/full/sci;319/5862/424 World Primary Energy Supply 2004 http://www.sciencemag.org/sciext/sustainability/ U.S. Energy use in 2005 http://www.sciencemag.org/sciext/sustainability/ Research money spent on alternative energy http://www.sciencemag.org/sciext/sustainability/ Much of our Alternative Energy Research is in Biofuels ~28% of U.S. energy is used in transportation http://www.eia.doe.gov/kids/energyfacts/uses/transportation.html U.S. Department of Energy, Transportation Energy Data Book: Edition 26-2007. In 2005, there were almost 239 million vehicles (cars, buses, and trucks) in the United States. http://www.eia.doe.gov/kids/energyfacts/uses/transportation.html U.S. Department of Energy, Transportation Energy Data Book: Edition 26-2007. Automobiles, motorcycles, trucks, and buses drove nearly 3.0 trillion miles in 2005. That’s almost 1/12th the distance to the nearest (non-sun) star. It’s like driving to the sun and back 13,440 times. Transportation fuel use http://www.eia.doe.gov/kids/energyfacts/uses/transport ation.html U.S. Department of Energy, Transportation Energy Data Book: Edition 26-2007. Vehicle Energy Use http://www.eia.doe.gov/kids/energyfacts/uses/transportation.html U.S. Department of Energy, Transportation Energy Data Book: Edition 26-2007. Ethanol vs Gasoline prices http://www.sciencemag.org/sciext/sustainability/ Biofuel production http://www.sciencemag.org/sciext/sustainability/ Fermentation: break down sugar to ethanol http://www.iogen.ca/images/m1 _fuel_cycle2.jpg Lignin removal is necessary for cellulose processing Nature Biotechnology 20, 557 - 558 (2002) CB 36.2 Water and minerals move up from the ground in xylem. water transport limits plant growth Most of wood is xylem CB 35.20 Xylem is tough, and full of lignin- inhibits the ability to use plants to produce biofuels xylem Lignin removal is necessary for cellulose processing Nature Biotechnology 20, 557 - 558 (2002) Research is ongoing to produce woody and non-woody plants with decreased lignin to improve the efficiency of biofuel production xylem Biofuel production http://www.sciencemag.org/sciext/sustainability/ Much of our Alternative Energy Research is in Biofuels Human resource production and use Worldwide Grain Production per Person http://www.earth-policy.org/Updates/2008/Update69.htm World Grain Stocks as Days of Consumption http://www.earth-policy.org/Updates/2008/Update69.htm ~60 percent of the world grain harvest is consumed as food, ~36 percent as feed, and ~3 percent as fuel. While the use of grain for food and feed grows by roughly 1 percent per year, that used for fuel is growing by over 20 percent per year. http://www.earth-policy.org/Updates/2008/Update69.htm Corn prices late 1999 - Dec 2007 Wheat prices http://www.earthpolicy.org/Updates/2008/ Update69.htm http://www.earth-policy.org/Updates/2008/Update69.htm Increasing oil prices drive up potential profit, and cost of food crops Cost of oil----Profitable cost of corn for ethanol $50 ---- $4/bushel $100 ---- $7/bushel $140 ---- $10/bushel Current corn price: ~$8/bushel http://www.farmdoc.uiuc.edu/manage/newsletters/fefo07_11/fefo07_11.html http://www.earth-policy.org/Updates/2008/Update69.htm Whereas previous dramatic rises in world grain prices were weather-induced, this one is policy-induced and can be dealt with by policy adjustments. If the entire U.S. grain harvest were converted into ethanol, it would satisfy scarcely 18 percent of our automotive fuel needs. http://www.earth-policy.org/Updates/2008/Update69.htm