Transcript PowerPoint Presentation - GHGs in Earth’s atmosphere

NATS 101
Lecture 34
Climate Change (cont’d)
The 6th Mass Species
Extinction?
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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
Trenberth
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 Might We Do?
• 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:
1. The amount of carbon in the fuels we use,
2. Our inefficient use of energy,
3. Our choices about when and how to use
energy
US Energy Usage
Inefficiency of Electricity Generation
31% efficient
Trenberth
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 Might We Do?
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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 Might We Do?
Four (?) coupled issues:
1. The threat of anthropogenic global change, warming
etc.
2. The international economics of the world’s fossil fuel
dependence
3. The international politics of our fossil fuel
dependence
4. 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
In 1931, 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
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
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-in installations 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