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Climate Change

Climate Change. Jess Everett Rowan University 2009. Natural Climate Change. Earth movement around Sun Shape (eccentricity), tilt & precession affect surface sunlight Years - 100,000 (eccentricity), 41,000 (tilt), & 19,000 to 23,000 (precession) Sun intensity

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Climate Change

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  1. Climate Change Jess Everett Rowan University 2009

  2. Natural Climate Change • Earth movement around Sun • Shape (eccentricity), tilt & precession affect surface sunlight • Years - 100,000 (eccentricity), 41,000 (tilt), & 19,000 to 23,000 (precession) • Sun intensity • Reduced solar activity from 1400s to 1700s likely key factor in “Little Ice Age” • Volcano eruptions • Aerosols • Volcanic aerosols block sunlight & contribute to short term cooling • Tambora Volcano, Indonesia 1815, lowered global temperatures by as much as 5ºF ; historical accounts in New England describe 1816 as “the year without a summer” • CO2 • Volcanoes emit CO2, which causes warming • Higher past activity may have raised pre-historic CO2 levels & temperatures • Human activities now emit 150 times as much CO2 as volcanoes www.epa.gov/climatechange/science/pastcc.html

  3. CO2 & Temp Over Time www.epa.gov/climatechange/science/pastcc.html

  4. CO2 & Other GHGs • Multiple sunlight paths (left) • “Greenhouse Effect” (right) • Some IR energy escapes to space, most absorbed by greenhouse gases, warming Earth's atmosphere. • Atmosphere would be ~ 30° C (54° F) colder if it contained no greenhouse gases www.windows.ucar.edu/tour/link=/earth/climate/greenhouse_effect_gases.html

  5. Natural Feedback Loops • Changes in GHG concentrations • Heating/cooling of Earth's surface can change GHG concentrations • Global temp ↑, CO2↑ oceans  more warming • Global temp ↓, CO2↓ ocean  more cooling • Changes in ocean currents • Heating/cooling of Earth's surface can change currents • Play significant role in distributing heat around Earth • Can cause significant changes in regional climates www.epa.gov/climatechange/science/pastcc.html

  6. Is current climate change human caused? • Natural factors do not explain recent climate change • Lines of Evidence • Understanding of climate system & GHG heat absorption • Paleoclimate reconstructions put recent warming in context • CO2 and/or temperature: tree rings, ice cores, corals, bore holes • Consistency between observations & computer model predictions • Fingerprinting: unique & characteristic signatures • Change in sun's energy output has different than increase in CO2 • Different statistical methods & variables point to climate change • surface temperature, sea level pressure, vertical patterns of atmospheric temperature change & ocean heat content Adapted from NPR interview with Ben Santer, climate scientist at Program for Climate Model Diagnosis and Intercomparison at Lawrence Livermore National Lab, early 2007

  7. UN (2007) “Case Studies on Climate Change and World Heritage Sites”

  8. Best Scientific Assessment • Intergovernmental Panel on Climate Change (IPCC) • Many scientists reviewing many studies • Conservative in drawing conclusions

  9. IPCC 2007 report • Warming of climate system unequivocal • Global average air & ocean temp ↑ • widespread melting of snow & ice • Global average sea level ↑

  10. Australia & New Zealand (ANZ), Polar Regions (PR), Terrestrial (TER), Marine and Freshwater (MFW), Global (GLO) IPCC 2007 report

  11. IPCC 2007 report Global GHG emissions due to human activities have grown since pre-industrial times, increase = 70% between 1970 & 2004

  12. IPCC 2007 report Most of observed increase in global average temperatures since mid-20th century very likely due to observed increase in anthropogenic GHG concentrations

  13. IPCC 2007 report Continued GHG emissions at or above current rates would cause further warming and induce many changes in the global climate system during the 21st century that would very likely be larger than those observed during the 20th century

  14. NJ Union of Concerned Scientists, “New Jersey, Confronting Climate Change in U.S. Northeast”, 2008

  15. Source: Emission Database for Global Atmospheric Research version 3.2

  16. GHG Mitigation - 15 Strategies • Stabilization Wedge Game (8 of 15 will do the trick) • Efficiency & Conservation • Increased transport efficiency • Reducing miles traveled • Increased building efficiency • Increased efficiency of electricity production • Fossil-Fuel-Based Strategies • Fuel switching (coal to gas) • Fossil-based electricity with carbon capture & storage (CCS) • Coal synfuels with CCS • Fossil-based hydrogen fuel with CCS • Nuclear Energy • Nuclear electricity • Renewables and Biostorage • Wind-generated electricity • Solar electricity • Wind-generated hydrogen fuel • Biofuels • Forest storage • Soil storage (changing agricultural processes) CMI, Princeton University

  17. Another Perspective • 10 solutions (Biello (2007) 10 Solutions for Climate Change, scientific American, www.scientificamerican.com, accessed, 1/10/2013) • Less Fossil Fuels • Infrastructure Upgrade • Move Closer to Work • Consume less • Be Efficient • Eat Smart (Vegetarian) • Cut Down Fewer Trees • Unplug device when not in use • One Child • Better Fuels

  18. And Again • Climate Change Engineering - Deliberate large-scale interventions (Wikipedia, accessed 1/10/2013) • Solar Radiation Management • White roofs and pavements • Cloud whitening with sea water • Reflective aerosols • Carbon Dioxide Removal • Biochar (burying charcoal) • Energy production coupled to carbon sequestration • Capture from ambient air • Ocean fertilization of capture carbon in organisms

  19. What can individuals do? • Become carbon-conscious • Typical US resident emits 5 x • Drive an energy efficient vehicle (or don’t drive at all) • Look for Energy Star label • Choose clean power • Unplug underutilized freezer or refrigerator • Get a home energy audit • Use CFLs • Buy good wood • Spread the word &help others • Let policy makers know you are concerned

  20. Myths perpetuated by non-technical columnists, e.g., George Will • In 1970s, major cooling of the planet was widely considered inevitable … the world's climatologists agreed that we needed to prepare for next ice age • Review of climate science literature 1965 - 1979 shows this is false. It is based on a selective misreading of texts both by members of the media at the time and by observers today. In fact, emphasis on greenhouse warming dominated the scientific literature then. • Sea ice is increasing • Published evidence suggests that the increase in Arctic sea ice in 2009 was significantly lower than the average since 1979, and follows a very similar trajectory to that of 2006-07 • According to the University of Illinois' Arctic Climate Research Center, global sea ice levels now equal those of 1979 • According to the Arctic Climate Research Center this is not correct. The reduction in sea ice between 2009 and 1979 is roughly the size of Texas, twice. • According to the UN World Meteorological Organization [WMO], there has been no recorded global warming for more than a decade • The most recent WMO statement shows a continuing warming trend over the past decade, and reports that "the linear warming trend over the past 50 years (0.13C per decade) is nearly twice that for the past 100 years." George Monboit’s blog, www.monbiot.com

  21. “Researchers: Dire Future for South Jersey” • Non-profit hires consultant to prepare maps showing effects of global warming in SJ • Assumes ~3 ft seal level rise • Contends that IPCC report is 2 years out of date (it predicts 17 inch rise)

  22. A Perfect Storm? • Over Population • Resource Depletion • Pollution • Water Scarcity • Energy Scarcity • Climate Change • Political Instability

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