Support for Learning Midterm II-Handed out Thursday, Nov. 12 Participation-30% Extra Credit Paper (up to 2/3 of letter grade) –5-10 pages –Subject of your choice –5-10 references (at least 3 not on the internet) –Discuss with Jason or Bob (email OK) Contact Jason or Bob BlackBoard –Powerpoints –Lecture Notes –Study Lists Reading –Notebooks, notes
The Greenhouse Effect Image courtesy of scrappy annie, Flickr.comscrappy annie
Greenhouse Effect Image courtesy of National Park Service, U.S. Department of the InteriorNational Park Service
Energy Budget Image courtesy of Robert A. Rohde, WikipediaRobert A. Rohde
Model http://ccl.northwestern.edu/netlogo/models/ ClimateChange
Greenhouse Effect Natural Greenhouse Effect –Raises earth’s average temperature 18C to 14C Anthropogenic Greenhouse Effect Enhancement –Due to additions of greenhouse gases –CO 2, CH 4, N 2 0, O 3, Freons CO 2 and Temperature correlated over last 2 million years CO 2 has never been as high as it is today Model predictions need historical data as well as a complete understanding of feedback systems and thresholds
Glacial/Interglacial Images removed due to copyright restrictions.
Other Feedback Systems Increased CO2 increased T ice caps melting decreased albedo increased T (POSITIVE feedback) Increased CO2 increased photosynthesis decreased CO2 (NEGATIVE feedback) Increased T increased evaporation increased clouds increased albedo decreased T (NEGATIVE feedback) Increased CO2 Increased T increased climate change disruption of ecosytems decreased productivity increased CO2 (POSITIVE feedback)
Thresholds Ocean Conveyor Belt stops –Temperatures rise, arctic ice melts, North Atlantic Deep Water not salty enough to sink Terrestrial carbon sink fills up –Forest regrowth complete –~1 gigaton C/yr atmospheric increase above current El Nino intensifies –Temperatures rise, cause greater gradients in pressure, disrupts upwelling and therefore productivity Hurricanes intensify –Water temperatures increase –Allow many more hurricanes to develop –Disrupts ecosystems
What can we learn from Past climate change? Images removed due to copyright restrictions.
Global Temperatures-Ice Ages Milankovitch Cycles Image courtesy of Robert A. Rohde, WikipediaRobert A. Rohde
Carbon Dioxide Image courtesy of Robert A. Rohde, WikipediaRobert A. Rohde
Current Interglacial Image courtesy of Robert A. Rohde, WikipediaRobert A. Rohde
Image courtesy of Robert A. Rohde, WikipediaRobert A. Rohde
Sun Spots Image courtesy of Robert A. Rohde, WikipediaRobert A. Rohde
Effect on Species Images removed due to copyright restrictions.
Effects of Climate Change Agriculture Shifts in food growing areas Changes in crop yields Increased pests crop diseases, and weeds in warmer areas Biodiversity Extinction of some plant and animal species Loss of Habitats Disruption of aquatic life Weather Extremes Prolonged heat waves and droughts Increased flooding from more frequent, intense, and heavy rainfall in some areas Water Resources Changes in water supply Decreased water quality Increased drought Increased flooding Snowpack reduction Melting of mountaintop glaciers Human Population Increased deaths from heat and disruption of food supplies More environmental Increased migration Forests Changes in forest composition and locations Disappearance of some forests especially ones at high elevations Increased fires from drying Loss of wildlife habitat and species Sea Level and coastal Areas Rising sea levels Flooding of low-lying islands and coastal cities Flooding of coastal estuaries, wetlands, and coral reefs Beach erosion Disruption of coastal fisheries Contamination of coastal aquifers with salt water Human Health Decreased deaths from cold weather Increased deaths from heat and disease Disruption of food and water supplies Spread of tropical diseases to temperate areas Increased respiratory disease and pollen allergies Increased water pollution from coastal flooding Increased formation of photochemical smog Images removed due to copyright restrictions.
Methods to slow Possible Global Warming Prevention Cut fossil fuel use (especially coal) in half Improve energy efficiency Shift to renewable Energy Reduce deforestation Use sustainable agriculture Slow population growth Cleanup Remove Co2 from smoke stack and vehicle emissions Plant and tend trees Images removed due to copyright restrictions.
CO2 Sequestration Image courtesy of U.S. Department of Energy under public domain
Carbon Sequestration Images removed due to copyright restrictions.
130 Gt total U.S. sequestration potential Global emissions 6 Gt/yr in 2002 Test sequestration projects 2002-2004 CO 2 Burial: Saline Reservoirs Study Areas One Formation Studied Two Formations Studied Power Plants (dot size proportional to 1996 carbon emissions) DOE Vision & Goal: 1 Gt storage by 2025, 4 Gt by 2050 Near sources (power plants, refineries, coal fields) Distribute only H 2 or electricity Must not leak At 2 Gt/yr sequestration rate, surface of U.S. would rise 10 cm by 2100
Projected Carbon-Free Primary Power 2005 usage: 14 TW