Can we have our
planet and heat it, too?
P310/P510 Fall 2011
Climate Discussion
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My conclusions
The greenhouse effect
Climate change – CO2
Climate change - temperature
What the models say
Recent Data
Frost Fair on the Thames 1683
During the mini-ice age the Thames froze
solidly on many occasions. London Bridge
with more than 100 shops was built in 1209
and was the only bridge across the Thames
until the late 1700’s.
My Conclusion
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That we are obliged to move away from
our own non-sustainable and climatedamaging fossil fuel use as quickly as
possible. BBB – 6/19/2010
“If not for the greenhouse effect, we may have been able to
postpone (the decision to look beyond fossil fuels) to the 22nd
century, because there are massive coal reserves available, and
coal can be made into synthetic fuels. We could have developed
the world economy based on fossil fuels …. But with the
greenhouse effect, we have to make the transition much earlier,
perhaps in the early 21st century. That means that we have to look
very seriously at the alternatives.”
Martin Hoffert, Professor, New York University
Greenhouse
Effect*
Two transparent
windows:
Solar radiation –
visible (0.3-0.8 mm)
 Earth radiation –
infrared (7-15 mm)
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Major infrared absorbers:
CH4, Natural Gas
N2O, Nitrous Oxide
O3, Ozone
CO2, Carbon Dioxide
H2O, Water
CH4
N2O
O2,O3
CO2
* Piexoto & Oort
H2O
Global Surface Temperature to 2010
Goddard Institute for Space
Studies (US)
The graph shows global annual surface temperatures relative to 1951-1980
mean temperatures.
1.) The last decade was the hottest ever recorded.
2.) 2010 is the hottest year since records have been kept.
3.) The brown line shows the 5-year average: Long-term trends are more
apparent. (Image credit: NASA/GISS)
2011 Mauna Loa CO2
Mauna Loa Monthly Mean CO2 in
parts per million (ppm).
August 2011 390.02 ppm
August 2011 388.15 ppm
National Oceanic and Atmospheric
Administration (NOAA)
http://www.esrl.noaa.gov/gmd/ccgg/t
rends/
Last 1000 years of CO2
280 ppm
390 ppm
TOTAL
Total Sun = 1367 W/m-2
Since 2007:
Rapid loss of Arctic sea ice
Ice-free
Since 2007:
Recent sea-level rise measurements
Merrifield, et al., 2009:
(1993-2008) (3.5 ± 0.4) mm/yr
IPCC 2007:
(1993-2003) (3.1 ± 0.7) mm/yr
Climate Change: An Impacts Summary
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Snow pack in Himalaya, Rocky Mountains  summer drought in
downstream areas.
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Open Arctic water in summer absorbs far more solar energy than
when ice-covered. [Positive feedback]
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Ocean expansion (warming) and Greenland, Antarctica, Northern
Canada rapid melting  rapid glacial flow  Sea level rise
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Thresholds, when crossed, make rapid transitions:
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Fresh water melting into the North Atlantic slows the Gulf
Stream.
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Ocean surface temperature above 27oC  increased hurricane
frequency and severity.
MODELS
J. Hansen et al.,
Science 308, 1431, 2005.
Estimates of human &
natural forcings 18802005.
These forcings
reproduce the last 125
years of observed
temperatures.
Extrapolate model?
Atmosphere-Ocean General Circulation Model
(AOGCM)
Multi-model averages (IPCC 2007)
SUSTAINABILITY – “roughly, the ability to meet our needs without compromising
the ability of future generations to meet theirs.” Brundtland Commission (1987)
Depletion
Present Oil/Gas/U Near Term Climate Change
COAL
COAL
X
OIL
X
oil
X
GAS
X
gas
X
URANIUM
X
uranium
TAR SANDS
Innovation
Long Term
CARBON SEQ.
BREEDERS
X
SOLAR (P.V., Wind, OTEC, Biomass..)
FUSION
Martin Hoffert: If it were not for
climate change, we would have had an
additional 150 years to develop
alternative energy sources.
GAS CLATH.
GEOTHERMAL
“Wedges” of U.S. Carbon Displacement
Am. Solar Energy Society’s “Tackling Climate
Change in the U.S.”
Conservation & Efficiency
Carbon Displacement by Region in Am. Solar Energy
Society’s, “Tackling Climate Change”
Carbon-neutral Energies
Biomass:
 Ethanol from sugar cane
 Biodiesel from soybeans, rape
seed, jatropha curcas
 Ethanol from cellulose
 Gasification to syngas
 Pellets from compressed
biomass waste – [CHP - UEA]
Geothermal storage:
 Vertical/horiz. loop systems
Solar:
 passive, active, wind  [T]
 OTEC, waves, tides
 Photovoltaics  [T]
 Direct Solar – e.g. Spain  [T]
 Direct – Stirling Engine ------>
Photovoltaics:
An Example in
Bloomington
http://physics.indiana.edu/~brabson
/PV/PV.html
https://www.hobolink.com/p/61f4
eecea80fc72d9b573157ac4ddec6
Mass. Audubon Center - Boston
Coal-driven steam – Norfolk, UK
Zicer Centre – UEA – Norwich, UK
Duke Energy - Grid
PV Array
Net Metering
Inverter
Home appliance
DC to AC
Breaker box
An Assessment of Photovoltaics
Yes
1.
2.
3.
4.
5.
6.
7.
8.
Carbon neutral energy source
In phase with need in summer
Mature technology (e=1820%)
Low maintenance
Long lifetime (>25 years)
Rapidly falling price
(Germany)
US Government subsidy
(30%)
Rising price of electricity
(Cost of carbon)
But
1.
2.
3.
4.
5.
Intermittent source (smart grid)
Expensive (Installed cost ~$4/watt
vs. $1.50/watt - coal)
Fast developing technology
Fragile (hail)
Installation dangers (falls)
Wind Turbines
How they work:
1. All electric generators push
wires through magnetic
fields
2. The mechanical energy 
electrical energy (95% eff)
3. Bicycle generators and
crank radios work the
same way.
4. Converting from the turbine
frequency to standard
frequency (60 Hz) is easy.
You convert to direct
current and back to
alternating current.
Wind Energy in the US
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1980-1996 US led wind power
1997-2007 Germany led.
2008 US took back the lead
(24,000 MW total)
2009 China now leads (10,000
MW new wind power)
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2008 World capacity 121,000 MW
27,000 MW new capacity (+29%)
New US electric generating
capacity in 2008:
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Natural gas 46%
Wind 42%
Coal 14%
Texas has 9,000 MW capacity
Indiana Wind
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Benton County Wind Farm
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130.5 MW (87 turbines, 1.5 MW)
April 2008 – Duke Energy will buy
the power for 20 years.
Fowler Ridge Wind Farm
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400 MW (182 Vestas 1.65 MW
turbines, 40 Clipper 2.5 MW)
200 MW (133 GE turbines, 1.5
MW)
An Assessment of
Wind Power
Yes:
1.) Carbon-neutral source
2.) Large renewable source
3.) Mature technology
4.) Cost competitive
(4¢/KWh)
5.) Off-shore (Cape Wind)
approval
But:
1.) Inadequate grid
2.) Land-based wind not
near population centers
3.) Locally intermittent
4.) Noise/Birds/Esthetics
My Conclusion
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That we are obliged to move away
from our own non-sustainable and
climate-damaging fossil fuel use
as quickly as possible. (BBB –
6/20/10)
1.) Anthropogenic CO2 raises the Earth’s
surface temperature.
2.) An estimated 80% reduction in CO2 by
2050 will avoid a 2oC temperature rise.
3.) Half of this reduction will come from the
use of carbon-neutral energy sources.
4.) The other half will come from reduced
energy use (conservation/efficiency)
5.) Changing our habits is not easy.
End of P310/P510 slides