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NATS 101 Lecture 34 Climate Change (cont’d). The 6th Mass Species Extinction?. Holocene Extinction: A 1998 survey by the American Museum of Natural History found that 70% of biologists view the present era as part of a mass extinction event, the fastest to have ever occurred.
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The 6th Mass Species Extinction? • Holocene Extinction: A 1998 survey by the American Museum of Natural History found that 70% of biologists view the present era as part of a mass extinction event, the fastest to have ever occurred. • Higher temperatures are moving rapidly toward the poles • Can species adapt/move quickly enough to avoid extinction? • Study of 1,700 species found poleward migration of 6 km/decade and vertical migration in alpine regions of 6 m/decade in past 50 years • These are within a factor of 2 of the surface isotherm migration in the Figure Hansen et al., 2006
CO2 emissions in different regions in 2000 in terms of emissions per capita (height of each block); population (width of each block); and total emissions (product of population and emissions per capita = area of block). Source: M. Grubb, http://www.eia.doe.gov/iea/ Trenberth
What MightWeDo? • Common sense precautionary measures suggest that we begin to reduce emissions before enormous changes to the climate and ecosystems could occur. • Greenhouse warming is internationally recognized as a serious problem. • Kyoto Protocol is a start, but the Congress and Executive branches have refused to ratify it or to support attempts to curb greenhouse emissions. • Support leaders and organizations who provide vision and can make tough decisions.
CO2 Emission-related News • China is now building about 2 power stations every week, BBC • Carbon Monitoring for Action CARMA • Database on international power plant emissions • In 2006, Supreme Court ruled (5 to 4) that CO2 is a pollutant covered by under the clean air act STORY • So EPA now has to regulate CO2 emissions! • Coal plant application denial in Kansas • SEN. Sam Brownback (R) response • Finally, new US Fuel efficiency standards? STORY
What is the Kyoto protocol? • The Kyoto protocol is an international and legally binding agreement to reduce greenhouse gas emissions worldwide. It came into force in February 2005 after being agreed at a 1997 UN conference in Kyoto, Japan. A total of 174 nations (but not the US) ratified the pact to reduce the greenhouse gases emitted by developed countries to at least 5% below 1990 levels by 2008-12. • Bali Conference (12/2007):a new international climate change deal is being negotiated to replace the Kyoto protocol that expires in 2012.
Energy usage and the CO2 problem The vast emissions of CO2 from energy use result from three factors: • The amount of carbon in the fuels we use, • Our inefficient use of energy, • Our choices about when and how to use energy
Inefficiency of Electricity Generation 31% efficient
Source of the problem • Beginning in the late 1950’s, our enormous energy addiction has pushed beyond the U.S. domestic production of fossil fuels • This addition has caused the US to become increasingly involved in the Middle East over time See: tonto.eia.doe.gov/FTPROOT/other/perspectives05.pdf
Present Financial Realities • How much do we spend a day buying crude oil? We presently import ~10 million barrels of oil per day At ~$100/barrel,$1B leaves the U.S. each day • How much do we spend each day on the Iraq War? Presently $10B/month = $330M/day in direct military Others estimate $720M/day in long term costs with no end in sight • Iraq funding is sufficient to fund a major new climate observing system or a new mission to Mars EVERY DAY
Petroleum Imports • We are spending at least $1.3B/day to gain access to fossil fuel which is causing CO2 concentrations to increase and our climate to change • Clearly $ are available for alternative fuel development if we decide to set our priorities to do so
What MightWeDo? • The climate is warming. The general scientific consensus is most of this is human induced • The CO2 problem will get worse: Within 15 years, China will surpass the U.S. as the world leader in carbon emissions • Concern about shifting from fossil fuels will adversely affect our economy has been used to justify a “wait and see” attitude • However, the early warning/warming signs are becoming commonplace and the potential damage from global warming and real damage from financial and political costs of our fossil fuel addiction argue that changes are needed and the sooner the better
What MightWeDo? Four (?) coupled issues: • The threat of anthropogenic global change, warming etc. • The international economics of the world’s fossil fuel dependence • The international politics of our fossil fuel dependence • The economics of breaking our dependence on fossil fuel Is there a Common solution? • Clearly we need to develop alternate fuel sources to get us off of our Fossil Fuel addiction (as Jimmy Carter suggested 30 years ago)
Suggestion The U.S. should become the world leader in developing alternative energy sources. • Reduce our greenhouse gas emissions • Develop new jobs in the U.S. • Reduce (or eliminate) our reliance on the Middle East • Export the alternative energy technology to other parts of the world for profit and to reduce their CO2 emissions
Alternative Energy Solutions • Bioenergy • Fuel Cells and Alternative Fuel Vehicles • Geothermal Energy • Solar Energy • Water Power or Hydropower • Wave, Tidal, or Ocean Energy • Wind Energy • Roscoe Texas wind farm NPR story See: http://www.aresearchguide.com/energy.html
Biofuels • Ethanol and biodiesel both used presently • 3/28/2005 -- Ethanol generates 35% more energy than it takes to produce (Michael Wang at US Department of Energy's Argonne National Laboratory). • http://journeytoforever.org/ethanol_energy.html • PROBLEM: Crutzen et al. (2007): biodiesel from rapeseed and bioethanol from corn (maize), can contribute as much or more to global warming by N2O emissions than cooling by fossil fuel savings • Also driving up the cost of corn
Biofuels: Algae? Algae may be the long term biofuel of the future. • Still some significant technical problems to overcome • Some BIG Advantages motivate research: • Yields of oil from algae are orders of magnitude higher than those for traditional oilseeds • Algae can grow in places away from the farmlands & forests, minimizing damage to the eco- and food chain systems. • Algae can be grown in sewages and next to power-plant smokestacks where they digest the pollutants and give us oil! See for example: http://www.oilgae.com/
Solar Energy In1931, Thomas Edison said: “I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.” • Ultimately the sun is the source of all power • Globally averaged solar power is 240 watts per square meter (higher at equator, lower at poles) • ~2000 W per person is needed for residential electricity • At 10% efficiency, ~80 sq. meters (30 ft x 30 ft) of solar energy collection is required per person • (at 6B humans, surface area per human is 1000x1000 ft)
Solar Power in Southwest http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/
Solar Collectors… • Lots of sunlight in the West • Collectors concentrate the solar energy to generate steam to run turbines • No CO2 emission • Problem for Southwest is they use water
Solar Power: Solar cells • Use in central power grids and individual buildings • Centralized grid does work because DC-AC inverters are 96% efficient • Tucson Electric Power (TEP) experimental grid in Springerville • A storage capability must be developed to smooth through diurnal and cloud-caused power variations
Solar Cells cont’d • Payback time of energy used in fabrication • from about 1 year for roof integrated built-ininstallations in Phoenix made from high efficiency amorphous Silicon • Over 30-year lifetime, Si based solar cells will produce 6 to 31 times the amount of energy used to produce them • No GHG emissions during power generation • Energy generation cost is ~0.18 $/kWh in Arizona (TEP) • Monthly use of 500 kWh per house: $90 (TEP cost ~$40) • TEP anticipates solar cells become cost effective ~2015 • Solar cells on the buildings in Tucson would provide the power needed for Tucson transportation via electric cars http://en.wikipedia.org/wiki/Solar_cell#Energy_conversion_efficiency
What Can YOU Do? • Use energy-efficient light bulbs • Initially more $, longer lasting, lower electricity $ • Purchase Energy Efficient Appliances/Merchandize • Limit Heating and Air Conditioning 76°F in summer, 66°F in winter • Think Alternative Transportation Bicycles, Walking, Public Transportation • Practice Smart Use of Personal Automobiles Carpool, Combine Errands, Lighter Loads, Slow Down Use Fuel Efficient or Hybrid Vehicles
Use solar power: • Dry your clothes on the clothes line • Some HOAs ban clothes lines: but clothes lines are environmentally beautiful • Solar water heaters on house • Solar electricity generation
Many things you can do: • Insulate your house etc: • Use renewable energy • Reduce coal fired power (unless carbon capture and storage employed)
Many things you can do: • VOTE! • Vote for responsible candidates • Most important!
Conclusions • Global warming (etc.) is very real • Humans are causing a lot of the problem • More climate change is a sure bet - we must develop adaptation strategies Arizona population projected to double by 2030 Photo: J. Overpeck
The Challenge: Sustainable Management of an Ever-Changing Planet