Download Global Warming

061514
1
Global Warming – So What?
Gene R. H. Fry
Abstract - Since 1880, Earth’s surface has warmed the fastest
in many millions of years. Oceans now gain more energy per 2
years than cumulative human energy use. Since 1993, the US
warmed very fast: 1.2°F / decade. That pace turns Kansas,
“breadbasket of the world,” into desert by 2100, while 2012 US
heat becomes its new normal in 2020. Sulfate level variations
explain temperature deviations from a smooth CO2-induced trend.
Current CO2 levels entail large lag effects: ~1.7°C, on top of
1.04°C (land) since 1913: 0.5-0.6°C each from Arctic Ocean
albedo changes, phasing out coal’s sulfur emissions (both
complete by 2100), and warming Earth enough so outgoing
radiation equals its heat gain. This CO2 level-temperature
relation is supported by multiple paleoclimate studies. Carbon
emissions from permafrost can increase warming more, even
absent further human CO2 emissions.
In 1990, Rind et al. projected that, warmed 4.2°C by CO2
double 1750 levels, Earth’s “1/century” drought frequency would
rise to 45% by 2059. This results in savannas, prairies and deserts
replacing forests; 70% lower biological net primary productivity;
and 30-50% losses in America’s major food crops. In 2004, Dai et
al. found that actual 1950-2002 severe drought frequency
matched Rind’s projections.
Farmers have staved off crop declines by mining groundwater,
notably in north China, north India, central California and the
Great Plains. Most major wheat producers (plus the Amazon,
twice, among others) have suffered 1/century droughts in the past
decade. Grain yields per hectare have plateaued worldwide since
2008. Several studies found that warming cut crop yields, such as
10%/°C warming. One warned of 37-82% crop losses by 2100,
due to heat spikes. Doubled world food commodity prices from
2007 to 2011 led to food riots and toppled governments.
The world may lose of up to half its food supply, perhaps by
2100, featuring water wars. Human population could fall steeply,
threatening civilization’s collapse. But other species would fare
worse. A study estimated the present value of projected warming
damages exceeds gross world product, cutting GWP by 3%/year.
It is vital not only to reduce CO2 emissions to zero (many
methods are reviewed), but go carbon-negative in a big way.
Major ways to move carbon from air to soils or elsewhere include
fast-rotation grazing, organic (and no-till) farming, accelerated
rock weathering, and farming the ocean.
Index Terms—US warming, droughts, food supply, bio-CCS.
I. INTRODUCTION
This review emphasizes impacts from and solutions to rapid
warming. Bottom line: we should pay ranchers and farmers to
move carbon from the air back into soils.
Why? We already have too much CO2 in the air. Warming
(since 1880) could well triple, even without more CO2. Blame
vanishing Arctic sea ice (0.5-0.6°C more warming), phasing
out coal’s sulfur emissions (similar), and warming Earth
enough so energy out = energy in (similar). Moreover, carbon
in permafrost could increase atmospheric CO2 levels by 100
ppm or more, even without further human carbon inputs.
Manuscript received June 6, 2014. Gene R. H. Fry is retired.
(phone 781-698-7176; e-mail [email protected]. website
www.globalwarming-sowhat.com)
Water
Rainfall becomes more variable. Planet-wide, we get a little
more rain. Around the Arctic gets lots more, but mid-latitudes
(20-40°) mostly get less than now. Yet in any one place, we
get
more hours and days without rain [1]. That is, we get
more downpours and floods, yet also longer, drier, hotter
droughts.
II. THE TEMPERATURE RECORD
Recent US Warming
US daily high temperatures, June 1 thru September 30, rose
steeply over 1978-2012, especially over 1993-2012 - for 26
cities with declining urban heat islands, scattered around the
US.1 Results are very similar for 81 more US cities, not shown.
Figure 1. US Mean High Temperatures, June 1 – Sept. 30
Consider Salina, Kansas, in the heart of wheat country,
breadbasket of the world. Warming at 3.3°C [5.9°F] / century,
by 2100 summer in Salina would be as hot as Dallas now. At
7.0°C [12.6°F] / century, by 2100 it would be as hot as
summer now in Las Vegas, where no crops grow.
Warming at the 107-city, 1993-2013, 6.7°C rate (faster in
central states), 2012 US heat becomes its new normal in 2020.
CO2 Levels: Now and Then
The CO2 level in Earth's atmosphere is now 400 ppm. That
is up 43% since 1750 and 36% since 1880, when NASA
temperature records began. In 1915, CO2 passed the 300 ppm
maximum between the last several ice ages.
400 ppm was last exceeded 15 million years ago [2]. 15-20
million years ago, Earth was 3-6°C warmer than now and seas
were 25-40 meters higher [2]. CO2 levels were as high as now
3.0-3.5 million years ago [3], [4]. Earth then was 2-3°C
warmer and seas were 20-35 meters higher [3], [4]. This means
1
Places are Aspen CO, Astoria OR, Bartow FL, Boston MA, Bristol
TN, Butte MT, Canton OH, Duluth MN, Elmira NY, Enid OK,
Ferndale MD, Hampton VA, Hanford CA, Houma LA, Jasper IN,
Macon GA, Moline IL, Newark NJ, Norfolk NE, Oakland CA, Rolla
MO, Roswell NM, Saginaw MI, Tupelo MS, Waco TX, and Yuma
AZ. Missing data (from NOAA, via www.weathergrond.com) was
interpolated from nearby weather stations, adjusted for systematic
temperature differences. Implausible data (high ≤ low) are adjusted
(high = 2* average – low), interpolated as missing, or omitted.
061514
ice then was gone from almost all of Greenland, most of West
Antarctica, and some of East Antarctica.
CO2 levels now will likely warm Earth’s land surface ~
2.7°C, not just the 1.0°C seen to date. We face lag effects.
Current CO2 levels are already too high for us. So far, half the
CO2 we have emitted has stayed in the air [5]. The rest has
gone into carbon sinks - into oceans, soils, trees, rocks. This
natural sequestration could shrink, even reverse.
Ocean Heat Gain
Of the net energy absorbed by Earth from the Sun, ~84%
went to heat the oceans [6]. 7% melted ice, 5% heated soil,
rocks and trees, while 4% heated the air [6]. Since 2007, ocean
heat gain has switched to 70% below 700 meters deep [7].
Moreover, now 90% goes to heat oceans, while less heats air,
rock, and ice [7]. We notice air heating slower. Warming is
sensitive to the partition of heat gain between water and air.
Figure 2. Ocean Heat Gain [9]
Yearly ocean heat gain from 1967 to 1990 was 40 times US
yearly energy use [8], [9]. From 1991 to 2005, it was 70 times
as much. Since 2005, it has been 120 times as much. Ocean
heat gain since 1967 equals 3,000 years of US energy use.
Sulfate Cooling Effects
Figure 3. Sulfates Affect Surface Temperatures
The temperature baseline is 1951-80. Short-term (1-4 year)
effects of major volcanic eruptions are clear. So are 2-decade
trends, most up, some down, from sulfur emissions by
smokestacks (ppm numbers in rectangle near bottom [10]).
The IPCC estimated sulfates offset 30-40% of warming from
greenhouse gases [11], [12]. Abolishing them will warm Earth.
2
Earth Is Heating Up
Earth now absorbs 0.25% more energy than it emits: a 300
(±75) million MW heat gain [13]. 300 million MW = 70 x
world electric supply = 20 x human energy use. Absorption has
been accelerating, from near zero in 1960. Earth will warm
another 0.6°C, so far, just so it emits enough heat to balance
absorption [14].
Air at the land surface is 1.04°C warmer than a century ago.
Half that warming happened in the last 33 years. Air at the sea
surface is 0.8°C warmer than a century ago [15]. As Fig. 2
shows, the oceans have gained ~ 10 x more heat in 40 years
than cumulative human energy use.
III. IMPACTS – ICE, WATER, DROUGHT
Reservoirs in the Sky
Most mountain glaciers are shrinking ever faster - in the
Alps, Andes, Rockies, and the east and central Himalayas [16].
30% of Himalayan glacier ice vanished since 1980 [17]. When
Himalayan glaciers vanish, so could the Ganges River (and
others) in the dry season.
Mountain snows melt earlier, so California’s San Joaquin
River (Central Valley, US “salad bowl”) could dry up by July
in most years; in 2013 it again dried up much earlier [18]. The
Colorado River’s recent 10-year drought was the worst since
white men came [19].
Permafrost
Permafrost’s release of methane (CH4) in wet areas, and
CO2 in dry ones, revs up warming in a vicious circle. Thawing
Arctic permafrost holds
6 x the carbon ever emitted by our
fossil fuels = 2 x the carbon in Earth’s atmosphere [20].
Permafrost area shrank 7% from 1900 to 2000 [21]. It may
shrink 75% more by 2100 [22].
Already, permafrost carbon emissions approximate those
from US vehicles [23]. Thawing permafrost can add up to
~100 ppm of CO2 to the air by 2100, and ~300 ppm more by
2300, for up to 1.7°C more warming [24]. Seabed methane
hydrates and Antarctic permafrost hold much more carbon. We
may repeat the 6°C PETM warming 55 million years ago [25].
Polar Ice: Albedo and Sea Level
Arctic Ocean ice is shrinking fast. Minimum ice area fell
37% in 34 years [26], while volume fell 72%, 53% in the last
10 years [27]. The ice got thinner too! The bright ice could
melt away by fall in 3-7 years and be gone all summer in 7-20
[27]. The dark water absorbs far more heat than bright ice. As
ice recedes, Earth absorbs more heat; it will warm more, even
without more CO2: so far, like 20 extra years of CO2 [28].
Greenland’s net ice-melt rate rose 5 x in the past 15 years
[29]. So, the ice cap’s simple life expectancy fell from 60
millennia to 11. Its annual net melt-water is already 1/2 of US
water use [30]. Antarctica’s yearly net ice-melt (West minus
East) was ~ 1/3 of Greenland’s [29], but its melt rate doubled
over 2007-11 [30]. It has 9 x the ice and will last longer.
Seas will likely rise 0.2 to 2 meters by 2100 [31] and 30+
meters over centuries. Seas rose 1.5 meters / century from
13,000 to 6,000 BC [32]. This provides a starting-point
estimate for coming sea level rise rates. Warming is far faster
now, but only 1/3 as much ice is left to melt as in 13,000 BC.
Jet Stream, Drought, and Forest Fires
From 1979 to 2005, the tropics spread. Sub-tropic arid belts
grew ~140 miles toward the poles, a century ahead of schedule
[33]. That means our jet stream moves north more often [34].
061514
In turn, the US gets hot weather more often.
2011-12 was America’s hottest on record. Over September
2011 - August 2012, relative to local norms, 33 states were
drier than the wettest state (Washington) was wet [35]. In
2012, 44 of 48 states were drier than normal [35]. Severe
drought covered a record 35-46% of the US, for 39 straight
weeks [35]. Drought reduced the corn crop by 1/4. Record
prices followed [36]. The soybean crop was also hit hard.
By 2003, forest fires burned 6 x as much area / year as
before 1986 [37]-[39]. Pine bark beetles ravage western US
forests [40]. Annual US forest area burned is expected to
double again by 2050 [41].
Drought Frequency in Major Crop Producers
When I was young, the leading wheat producers were the
US Great Plains, Russia’s steppes, Canada, Australia, and
Argentina’s Pampas. “1/century” droughts now happen there
once a decade.
Table 1. Recent Extreme Droughts
When
Where
How Bad
Record heat, 20-70,000 die. Hotter in
2003
W Europe
2012
2003Worst in millennia. 100’s die. New
Australia
2010
record heat in 2013
Amazon Once / century. Worse in 2010, also
2005
Basin
bad in 2013-14 in Sao Paulo state
2007
Atlanta, SE Once / century
2007
Balkans
Record heat, Greek fires, 100’s die.
2007Record low rain in Los Angeles.
California
2009
All CA in extreme drought 2013-14
2008-9 Argentina Worst in half century
2008Tied for worst in 200 years. Severe
north China
2011
drought in Yunnan ‘09-13.
2009
India
Monsoon season driest since 1972
Record heat, forest fires, 15,000 die.
2010
Russia
World wheat prices up 75%.
2011
US: TX, OK record heat & drought
US: SW, Most widespread in 78 years, record
2012
MW, SE heat
Irrigation and Groundwater Loss
Over 1994-2007, deserts grew from 18 to 27% of China’s
area [42]. Since 1985, half the lakes in Qinghai province
vanished [43] and 92% in Hebei province [44] around Beijing,
as water tables dropped below lake beds. Many wells in
China’s wheat belt must go down 300+ meters for water [45].
Yearly net US groundwater withdrawals for irrigation grew
since 1950, from 13 to 25% of US water use now [46]. So, the
Ogallala Aquifer dwindles. 1/5 of wheat is irrigated in the US,
3/5 in India, and 4/5 in China [47]. Central California loses
enough to irrigation yearly to fill Lake Erie in 100 years [48].
Groundwater loss from India’s Ganges Basin would fill Lake
Erie in 10 [49]. With more evaporation and irrigation, many
water tables fall 1-6 meters / year [50]. Worldwide, irrigation
wells chase water ever deeper. Water prices rise.
Inland seas and lakes dry up and vanish, for example: the
Aral Sea, Lake Chad, Lake Eyre, and the Sea of Galilee. More
rivers fail to reach the sea more often: Yellow, Colorado,
Indus, Murray-Darling, Rio Grande, etc.
IV. IMPACTS: FOOD
Droughts Set the Stage
As Figure 4 shows, NASA’s model projected in 1990 that
3
with “Business as Usual” emissions, CO2 doubles (550 ppm)
1750 levels by 2059, causing 4.2°C warming and 14% more
rain [51]. It projected droughts increase in severity and extent,
so that “1/century” droughts cover 45% of Earth [51].
Extreme Drought Can Clobber Earth
By
2059,
a Century”
Can
45% of Earth.
Figure
4. “Once
Projected
Drought Drought
Conditions
in Cover
2059 [51]
Supply-Demand Drought Index
1969
1999 .
Busine
as Usu
Emissi
in 2059
2 x CO2
2029
2059
+4.2°C
+14% ra
Climate Mod
NASA
Goddard
Institute fo
Space Studi
(GISS)
DRY
WET
0
1
5
16
36
36
16
5
1
0
Run
Figure %5 Occurrence
shows thein Control
same projections
% in control run
Fig. 1 in David Rind, R. Goldberg, James Hansen, Cynthia
Rosenzweig, R. Ruedy, “Potential Evapotranspiration and
the Likelihood of Future Droughts,” Journal of Geophysica
Research, Vol. 95, No. D7, 6/20/1990, 9983-10004.
as a time series. Over
2000-04, the average frequencies are 18% for “drought” and
33% for “dry”. A weighted average for “as dry as 11% of the
time” drought is ~ 27%.
Figure 5. Projected Drought Conditions by Year [51]
In Figure 6, compare 30% actual severe drought area in
2002 (11% of the time during 1951-80) to 27% projected in
1990 (Figure 5) for 2000-2004. Droughts spread, as projected
or faster. Earth’s area in severe drought has tripled since 1979.
Evaporation worked its magic. Over 23 years, the area with
severe drought grew by the size of North America. From 1979
to 2002, comparably wet soil areas shrank from 11% to 8% of
Earth’s land area – by the size of India.
Figure 6. Historical Worldwide Drought Frequency [52]
061514
4
Over 1992-2003, warming above the norm cut corn, rice,
and soybean yields by ~10%/°C [59]. Over 1982-98, warming
in 618+ US counties cut corn and soybean yields ~17%/°C
[60]. With more CO2, 2°C warming cut
yields 8-38% for
irrigated wheat in India [61]. Warmer nights since 1979
cut
rice yield growth 10%± in 6 Asian nations [62]. Warming
since 1980 cut
wheat yield growth 5.5%, corn 3.8% [63].
In Table 2 below, grains include wheat, corn, rice, barley,
oats, rye, and sorghum. Million tonnes in 2011 are from FAO,
yields from data.worldbank.org/indicator/AG.YLD.CREL.KG.
Table 2. World Cereal Grain Yields
US Climate Future This Century – UCS Study
In 2005-6, scientists calculated how climate would change
for 9 Northeast [53] and 6 Great Lakes [54] states in 2 cases:
(1) a transition away from fossil fuels, or
(2) continued heavy
reliance on them (business as usual emissions).
In 2085, averaged across 15 states, climate change would
be like moving 530 km SSW (if coal and oil use shrink) or
moving 1050 km SSW (if heavy use continues) [53], [54].
Consider central Kansas, heart of wheat country. 530 km SSW
sits the area from Amarillo to Oklahoma City. 1050 km SSW
is around Alpine and Del Rio, Texas, with <1 person / sq km.
Cactus, mesquite and sagebrush grow there, but no wheat.
Droughts - Why Worry?
In 2059, with 2 x CO2 (Business as Usual emissions), Earth
has more moisture in the air, but 15-27% less in the soil [51].
Average US stream flows decline 30%, despite 14% more rain
[51]. Tree biomass in the eastern US falls by up to 40% [51].
More dry climate vegetation replaces forests: savannas,
prairies, and deserts [51]. The vegetation changes mean
biological net primary productivity falls 30-70% [51].
Switching from projections to actuals, satellites show that
browning of the Earth began in 1994 [55].
Crop Yields Fall
NASA made 2059 projections for the United States, with
doubled CO2 (Business as Usual emissions) in the Great Lakes,
Southeast, and southern Great Plains regions - for corn, wheat,
and soybeans. NASA’s GISS model projected (4.2°C warmer,
14% more rain) that crop yields would fall 30%, averaged
across regions and crops [51]. NOAA’s GFDL model
projected (4.5°C warmer, 5% less rain) they would fall 50%,
averaged across regions and crops [51].
CO2 fertilization was not included [51]. So things will not
be this bad, especially this soon. Temperature effects of
doubled CO2 will keep growing, eventually to 4.2° or 4.5°C,
but over many decades. CO2 fertilization (2 x CO2) boosts
yields 4-34% in experiments [56], [57] where water and other
nutrients are well supplied, and weeds and pests are controlled.
That will not happen as well in many fields. Groundwater and
snowmelt for irrigation grow scarcer in many areas. Other
factors (most often nitrogen) soon kick in to limit growth, so
CO2 fertilization will falter some.
Crop Data Analyses
As Table 2 shows, worldwide yields for cereal grains have
leveled off. This is consistent with rising food prices, and with
forecasts of falling crop yields. However, global population is
expected to grow, leading to much less food per person.
For wheat, corn, and rice, photosynthesis in leaves
slows
above 35°C (95°F) and stops above 40°C (104°F) [58].
Warming (above 35° or 40°C) hurts
warm, tropical areas
harder and sooner [58].
Heat Spikes Devastate Crop Yields
Average yields for corn and soybeans could plummet 3746% by 2100 with the slowest warming and 75-82% with
quicker warming [64]. Why? Corn and soybean yields rise
with warming up to 29-30°C, but fall more steeply with higher
temperatures [64]. Heat spikes on individual days have big
impacts [64].
More rain can lessen losses, since plants transpire more
water to cool off. Growing other crops, or growing crops
farther north, can help too.
Figure 7. Possible Changes in World Crop Yields, +3°C [65]
061514
Figure 7 shows a possible future crop yield scenario. It is
more pessimistic than the average among many studies. Like
most projections, it does not include CO2 fertilization.
World Food Prices
Due in part to heat and drought stresses on crops, and with
yields per hectare flat, the world food price index rose [65].
Climate change probably played a role in that food situation.
Figure 8. World Food Price Index [66]
With food stocks at low levels, when food prices rose
steeply in 2007-08 and again in 2010 (Figure 8), poor people
could not afford to buy enough food. Malnutrition and
starvation rose. Food riots toppled governments in 2011.
V. IMPACTS: SUMMARY AND COSTS
Projected Warming Effects by Degree [67]2
2°C Warming - 450 ppm CO2e 3
• Hurricane costs double. Many more major floods
• Major heat waves are common. Forest fires worsen.
• Droughts intensify. Deserts spread.
• Civil wars and border wars over water increase. [68]
• Crop yields rise nowhere, fall in the tropics.
• Greenland icecap collapse becomes irreversible.
• The ocean begins its invasion of Bangladesh.
3°C Warming - 550 ppm CO2e 4
• Hurricanes and droughts get much worse.
• Hydropower and irrigation decline. Water is scarce.
• Crop yields fall substantially in many areas.
• More water wars and failed states. Terrorists multiply. [68]
• 2/3 of Amazon rainforest may turn to savanna, desert scrub.
[69]-[72]. (Since 1979, the Amazon dry season has lengthened
by a week per decade [73].)
• Tropical diseases (malaria, etc.) spread farther and faster.
4°C Warming - 650 ppm CO2e
• Water shortages afflict almost all people.
• Crop yields fall in ALL regions, by 1/3 in many.
• Entire regions (e.g., Australia) cease agriculture
altogether.
• Water wars, refugee crises, terrorism become
intense. [68]
• Methane release from permafrost accelerates.
2
3
4
selected effects from the Stern Review [67], except as noted.
includes CH4, SO4, etc. 2°C effects are unavoidable.
Current CO2e level is ~ 540 ppm.
5
• The Gulf Stream may stop, monsoons often fail.
• West Antarctic ice sheet collapse speeds up.
5°C Warming - 750 ppm CO2e
(my extrapolations) .
• Deserts grow by 2 x the size of the US.
• World food falls by 1/3 to 1/2.
• Human population falls a lot, to match a reduced
food supply.
• Other species fare worse.
$ Costs
Costs (inflation-adjusted $, Business as Usual) of inaction
are now $695 billion / year [74] (> 1% of GWP), including
$119 billion ($380 / American) in the US for 2012 [75] (almost
1% of US GNP). Already 0.5 million people a year die from
climate change worldwide, plus 4.5 million from sulfates [74].
Costs grow over time. The present value of future costs
(2005-2200, at 2%/year) with “business as usual” emissions
was estimated in 2005 at €74 trillion [76] (~$100 trillion). This
exceeds GWP. Annualized damages are $2 trillion / year (3%
of GWP). This is like a hidden tax of $50,000 / American. The
damages translate to $85 / Ton of CO2 [67].
In contrast, the costs of action are $9-75/year per American
[77], [78]. This means spending 1% ±2% of GWP ($150
billion by US), each year [67]. (Negative 1% is energy
efficiency.) In this case, damages fall to $25 - $30 / ton of CO2
[67] and world savings are about $2.5 trillion, net, from each
year’s spending [67], [79], a 5:1 benefit to cost ratio.
VI. SOLUTIONS
Remove Carbon from the Air.
• Rebuild rangelands. Perennial grass roots add
carbon to soil [80]. Speed up the process 10-50 x with short
rotation cattle grazing, like buffalo [81], across vast
rangelands. Dung beetles also move carbon underground, so
lots more rain soaks in [80]. This grazing practice can absorb
2.5 T of carbon (9 of CO2) / hectare / year [80], cutting
atmospheric CO2 by 6 ppm / year (3.5 net) [80], and 80 ppm
over only a few decades [81].
• Farming can put 4.3 GT of atmospheric CO2 / year into soils
(0.7 in US), for $20-100 / Ton [82], [83]. Organic farms add
more than 3 T of carbon (11 of CO2) / hectare / year to soil,
using no-till methods, composting, natural fertilizer, etc. [82][84]. This rebuilds soil organic matter, from 1-3% now, to 610% before farming. Increase humus (soil carbon+), with
mycorrhizal fungi, glomalin, and humate [82].
• Rocks have weathered for eons, taking 1 GT CO2 / year from
the air [85]. Move CO2 into crushed rock (basalt, etc.)
Spread around millions of 2-story towers with crushed rock
[86], to speed up natural process 10 x.
• Add iron filings to select ocean areas [87]. Algae bloom and
suck CO2 from the air. Algae must suck 8 x as much carbon
from the air as our food supply does, just to break even.
Oceans may be too small, even if fertilization works well.
Dead algae may not sink. Tiny creatures eat them; soon carbon
returns to air. Additional fertilizers (K, P, N, etc.) may be
needed. Other problems will arise.
• Bury biochar shallow in soils.
• Use carbon capture and storage in biomass-fired power plants
[88].
• Planting more trees is a good idea, but deforestation
continues for fuel, lumber, paper, palm oil, soybeans, ranches.
061514
Trees need water, but soils will have less. Forest fires run wild.
• Maintain forest soils: humus, roots, fungi, bacteria, leaf litter.
That is tough to do; drought and fires hurt. Below-ground
carbon is less than above-ground carbon in tropical rainforests,
but that relationship is strongly reversed in mid-latitude forests
[89], and especially in circum-polar ecosystems. (Permafrost
holds about 3 x as much carbon / ha as tropical rainforest.5)
• Add silicates during hydrolysis at sea surface [90]. Scrub
CO2 from the air.
Put Less Carbon in the Air
Electricity
Price it right retail, for everyone: low at night, high by day,
highest on hot afternoons. Price demand and energy separately.
• Coal - Use less. Scrub out the CO2 with oxyfuel or pre-/
post-combustion process [91].
• Natural gas and oil follow daily loads up and down, but oil is
costly. To follow loads, store energy in car batteries, water
uphill, flow batteries, compressed air, flywheels, molten salt,
hydrogen. Keep leaks from fracking to very low levels.
• Wind - Resource is many x total use: US Plains, coasts:
N. Carolina to Maine, Great Lakes, Gulf of Mexico. Growing
16-35%/year [92], it is often cheaper (4-8 ¢/kWh) than coal
[93], [94]. Wind is 5.6% of US GW [95]. Wind turbines off the
East Coast could replace all or most US coal plants [96].
• Solar - Resource dwarfs total use. Output peaks near when
cooling needs peak. Growing 30+%/year [92], solar PV costs
4-12 ¢/kWh [97], [94], thermal (with flat mirrors) 10¢ [98].
• Nuclear - new plants in China, India, Korea, US Southeast
• Water, Wood, Waste - Rivers will dwindle. More forest
fires limit growth.
• Geothermal - big potential in US West, Ring of Fire, Italy
• Ocean - tides, waves, currents, thermal difference (surface
vs deep: “OTEC”)
• Renewable energy can easily provide 80-90% of US
electricity by 2050 [99].
Efficient Buildings +
At Home
Use ground source heat pumps. Use better lights compact fluorescents (CFLs) and LEDs. Turn off un-used
lights. Use Energy Star appliances – air conditioners,
refrigerators, front load clothes washers. Insulate - high Rvalue in ceilings and walls, honeycomb window shades,
caulking. Use low flow showerheads, microwave ovens, trees,
awnings, clotheslines, solar roofs.
Commercial
Use micro-cogeneration and ground source heat
pumps. Don’t over-light. Use day-lighting, reflectors,
occupancy sensors. Use LCD Energy Star computers. Ventilate
more with variable speed drives. Use free cooling (open
intakes to night air), green roofs, solar roofs. Make ice at night,
then melt it during the day - for cold water to cool buildings
[100].
Industrial
Energy $ impact the bottom line. Efficiency is
generally good already. Facility energy managers do their jobs.
Case-specific process changes become economic as energy
5
Rainforests in the Amazon, Congo, and Borneo [Mongobay,
PLOS 1, etc.] store 300 tons of carbon/ha, on average.
Permafrost stores 1.9 trillion tons [20] of carbon, spread across
its 23.7 million sq km, that is 800 tons of carbon/ha.
6
prices rise. Use more cogeneration.
Personal Vehicles
US cars get 24 mi/gal (10 km/l), pickups, vans and SUVs
get 17 (7), averaging 20 (8.5) [101]. GM and Chrysler went
bankrupt. Toyota started outselling Ford in the US and GM
around the world. Hybrid sales are soaring, up to 56 mi/gal (24
km/l). New cars average 37-44 mi/gal (16-19) in Europe and
45 (19) in Japan [102].
To cut US vehicle CO2 by 50% in 20 years is not hard. GM
already did it in Europe. How? Lighten up, downsize, don’t
over-power engines. Use 5-speeds and continuously variable
transmissions, hybrid-electric, diesel. Ditch SUVs. Use pickup
trucks and vans only for work that requires them. Store wind
on the road, with plug-in hybrids. Charge them up at night.
Other Transportation
Fuels - Cut CO2 emissions further with low-carbon fuels?
Save ethanol and biodiesel for boats and long-haul trucks and
buses. Get ethanol from sugar cane
(energy out / in ratio =
8:1 [103]). But corn ethanol’s ratio is only 0.8 or 1.3 or 1.7:1
[104], [105]. We feed food to cars. Grain for ethanol to fill one
SUV tank could feed a man for a year [106]. Use cellulose?
Estimated energy out / in ratios also vary dramatically for both
palm oil and prairie grasses. For biofuels, more CO2 from
land use changes dwarf CO2 savings [107], [108].
Trains, Airplanes, and Ships - Use high-speed magnetic
levitated railroads (RRs) for passengers. Shift medium-haul
(150 - 800 miles) passengers from airplanes to maglev RRs
(faster than TGV, bullet trains). Shift long distance freight
from trucks to electric RRs.
Big cargo ships use 2 MW wind
turbines, hydrogen, nuclear reactors.
Personal
Make your home and office efficient; don’t over-size a
house. Drive an efficient car; don’t super size a vehicle.
Combine errands, idle 10 seconds at most. Walk. (Be healthy!)
Carpool, use bus, RR, subway. Bicycle.
Buy things that last. Fix them when they break. Eat less
feedlot beef; less is healthier! (1 calorie = 7-10 of grain.)
Reduce, re-use, recycle. Minimize packaging and use cloth
bags. Garden; move carbon from the air into the soil.
Ask Congress to price carbon. Cut CO2 emissions 80+% by
2050. Tax carbon 3¢/pound, rising 5% per year. Rebate the
tax revenue in equal amounts to each American. Include tax
credits to move CO2 from the air into soils, etc.
REFERENCES
[1] W. K.-M. Lau, H.-T. Wu and K.-M. Kim, “A canonical response of
precipitation characteristics to global warming from CMIP5 models,”
Geophysical Research Letters. 40(12) pp. 3163–3169. Jun 2013.
[2] A. K. Tripati, C. D. Roberts, R. A. Eagle, “Coupling of CO2 and ice sheet
stability over major climate transitions of the last 20 million years,”
Science. 326, pp. 1394-7. Dec 2009.
[3] M. Pagani, Z. Liu1, J. LaRiviere and A. C. Ravelo, “High Earth-system
climate sensitivity determined from Pliocene carbon dioxide
concentrations,” Nature Geoscience. vol. 3, pp. 27-30. Dec. 2009.
[4] A. Z. Csank, A. K. Tripati, W. P. Patterson, R. A. Eagle, N. Rybczynski, A.
P. Nallantyne, et al., “Estimates of Arctic land surface temperatures
during the early Pliocene from two novel proxies,” Earth and Planetary
Science Letters. 344(3-4), pp. 291-299. Apr. 2011,
[5] J. Hansen et al., “Doubling down on the Faustian bargain”, 2013.
[6] S. Levitus, J. Antonov, and T. Boyer, “Warming of the world ocean, 1955–
2003,” Geophysical Research Letters, vol. 32, L02604. Jan 2005
[7] M. A. Balmaseda, K. E. Trenberth,, and E. Källén, “Distinctive climate
signals in reanalysis of global ocean heat content,” Geophysical
Research Letters. 40(9), pp. 1754-1759.. May 2013.
[8] U. S. Department of Energy, Energy Information Administration [USDOE
/ EIA]. “Table 1.3 Primary Energy Consumption by Source”, Monthly
061514
Energy Review.
National Oceanic and Atmospheric Administration, Data Center.
www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/
[10] WG1 Figure SPM-2 in J. T. Houghton, Y. Ding, D. J. Griggs, M. Noguer,
P. J. van der Linden, X. Dai, et al. ed. Climate Change 2001: The
Scientific Basis. Contribution of Working Group I to the Third
Assessment Report of the Intergovernmental Panel on Climate Change.
Cambridge University Press. ISBN 0-521-80767-0.
[11] Figure SPM-2 in S. Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis,
K. B. Averyt, et al. (eds.), IPCC, 2007: Summary for Policymakers. In:
Climate Change 2007: The Physical Science Basis. Contribution of
Working Group I to the 4th Assessment Report of the Intergovernmental
Panel on Climate Change. Cambridge University Press, Cambridge, UK
and New York, USA.
[12] Figures TS-6 and TS-7 in T.F. Stocker, D. Qin, G.-K. Plattner, M. Tignor,
S.K. Allen, J. Boschung, et al. (eds.). IPCC, 2013: Climate Change
2013: The Physical Science Basis. Contribution of Working Group I to
the Fifth Assessment Report of the Intergovernmental Panel on Climate
Change [Cambridge University Press, Cambridge, UK and New York,
NY, USA.
[13] J. Hansen, M. Sato, P. Kharecha, and K. von Schuckmann, “Earth's
Energy imbalance and implications,” Atmos. Chem. Phys. vol. 11. pp.
13421-13449. 2011.
[14] J. Hansen, L. Nazarenko, R. Ruedy, M. Sato, J. Willis, A. Del Genio, et
al., “Earth’s energy imbalance: confirmation and implications”, Science.
308(5727), pp. 1431-1435. June 2005.
[15] NASA: http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
[16] D. Powell, “Himalaya Rush”, Science News. Aug 10, 2012.
[17] S. R. Bajracharya,, S. B. Maharjan, F. Shrestha, O.R. Bajracharya, S.
Baidya, “Glacier status in Nepal and decadal change from 1980 to 2010
based on Landsat data.” ICIMOD, Nepal. 2014.
[18] M. Grossi, “For San Joaquin River revival, drought becomes way of life,”
Fresno Bee, Apr. 5, 2014.
[19] U.S. Geological Survey, “Climatic fluctuations, drought, and flow in the
Colorado River Basin,” Fact Sheet 2004-3062, version 2. Aug. 2004.
[20] G. Hugelius, J. Strauss, S. Zubrzycki, J. W. Harden, E. A. G. Schuur,
C. L. Ping, et al., “Improved estimates show large circumpolar stocks of
permafrost carbon while quantifying substantial uncertainty ranges and
identifying remaining data gaps,” Biogeosciences Discuss. vol. 11, pp.
4771-4822. 2014.
[21] Figure SPM-2 in IPCC 2007: Summary for Policymakers. In: Climate
Change 2007: The Physical Science Basis. op. cit., p. 6.
[22] Figure 22.5 in Chapter 22 (F.S. Chapin III and S. F. Trainor, lead
convening authors) of draft 3rd National Climate Assessment: Global
Climate Change Impacts in the United States. Jan 12, 2013.
[23] E. Dorrepaal, S. Toet, R. S. P. van Logtestijn, E. Swart, M. J. van de Weg,
T. V. Callaghan, et al., “Carbon respiration from subsurface peat
accelerated by climate warming in the subarctic,” Nature. vol. 460, pp.
616-619. Jul. 30, 2009.
[24] A. H. MacDougall, C.A. Avis, and A.J..Weaver, “Significant contribution
to climate warming from the permafrost carbon feedback,” Nature
Geoscience. vol 5, pp. 719-721. Sep .9, 2012.
[25] R. M. DeConto, S. Galeotti, M. Pagani, D. Tracy, K. Schaefer, T. Zhang,
et al., “Past extreme warming events linked to massive carbon release
from thawing permafrost,” Nature. vol 484. pp 87-92. Apr. 5, 2012.
[26] http://neven1.typepad.com/blog/2011/09/historical-minimum-in-sea-iceextent.html
[27] Wipneus, https://sites.google.com/site/arctischepinguin/home/piomas
[28] S.R. Hudson, “Estimating the global radiative impact of the sea ice–
albedo feedback in the Arctic,” Journal of Geophysical Research:
Atmospheres. 116(D16), p102. Aug. 16, 2011.
[29] A Shepherd, E. R. Ivins, A. Geruo, V. R. Barletta, M. J. Bentley, S.
Bettadpur, et al., “A reconciled estimate of ice-sheet mass balance,”
Science. vol. 338, pp. 1183-1189. Nov. 30, 2012.
[30] M. McMillan, A. Shepherd, A. Sundal, K. Briggs, A. Muir, A. Ridout, et
al., “Increased ice losses from Antarctica detected by CryoSat-2”,
Geophysical Research Letters. May 2014. to be published
[31] Fig. 2.26 in J. Walsh, D. Wuebbles, et al., draft 3rd National Climate
Assessment: Global Climate Change Impacts in the United States. Jan.
12, 2013.
[32] R.A. Rohde, Figure “Post-Glacial Sea Level Rise”, based on research by
Fleming et al. 1998, Fleming 2000, and Milne et al. 2005. See, e.g.,
http://commons.wikimedia.org/wiki/File:Post-Glacial_Sea_Level-fr.svg.
[33] D. J. Seidel, Q. Fu, W. J. Randel, and T. J. Reichler, “Widening of the
tropical belt in a changing climate,” Nature Geoscience. vol 1, pp. 21-24.
Dec. 2, 2007.
[34] V. Petoukhov,S. Rahmstorf, S. Petria, and H. J. Schellnhuber,
[9]
7
“Quasiresonant amplification of planetary waves and recent Northern
Hemisphere weather extremes,” [PNAS] National Academy of Sciences.
110(14), pp. 5336-5341. Mar. 1, 2013.
[35] www.ncdc.noaa.gov/oa/climate/research/prelim/drought/zimage.html
[36] H. Yousuf, “Corn, soybean prices shoot up as drought worsens,”
CNNMoney. Jul. 12, 2012.
[37] A. L. Westerling, H. G. Hidalgo, D. R. Cayan, T. W. Swetnam,
“Warming and earlier spring increase Western U.S. forest wildfire
activity,” Science. 313(5789), pp. 940-943. Jul. 6, 2006.
[38] M.-A. Parisien, V. S. Peters, Y. Wang, J. M. Little, E. M. Bosch, and B.J.
Stocks, “Spatial patterns of forest fires in Canada, 1980–1999”,
International Journal of Wildland Fire. vol. 15, pp. 361-374. 2006.
[39] A. J. Soja, N. M. Tchebakova, N. H. F. French, M. D. Flannigan, H. H.
Shugart, B. J. Stocks, et al., “Climate-induced boreal forest change:
predictions versus current observations”, Global and Planetary Change.
vol. 56, pp. 274-296. 2007.
[40] J. B. Milton and S. M. Ferrenberg, “Mountain pine beetle develops an
unprecedented summer generation in response to climate warming,” The
American Naturalist. 179(5), pp. E163-E171. May 2012.
[41] D. L. Peterson and J. M. Vose, “Chapter 7: Conclusions” in J. M. Vose,
D. L. Peterson, and T. Patel-Weynand (eds.), “Effects of climatic
variability and change on forest ecosystems: a comprehensive science
synthesis for the U.S. forest sector.” U.S. Department of Agriculture,
Forest Service. General Technical Report PNW-GTR-870. Dec. 2012.
[43] L. Brown, “Chapter 3: Emerging Water Shortages: Disappearing Lakes”
in Plan B 2.0: Rescuing a Planet Under Stress and a Civilization in
Trouble. W. W. Norton & Company, New York and London, 2006, at p.
52, citing 3 sources.
[44] “20 natural lakes disappear each year in China,” People’s Daily, Oct. 21,
2002, cited by L. Brown in Plan B 2.0 on p. 52.
[45] L. Brown, op. cit., [43], p. 44.
[46] USGS, www.nationalatlas.gov/articles/water/a_wateruse.html
“Trends in population and freshwater withdrawals by source, 1950-2000.”
[47] L. Brown, Plan B: Rescuing a Planet Under Stress and a Civilization in
Trouble. New York: W. W. Norton & Company, 2003. See
http://www.earth-policy.org/books/pb/pbch_ss3, note 12.
[48] J. S. Famiglietti, M. Lo, S. L. Ho, J. Bethune, K. J. Anderson, T. H. Syed,
et al.,“Satellites measure recent rates of groundwater depletion in
California's Central Valley,” Geophysical Research Letters. vol. 38, L
03403. Feb. 5, 2011.
[49] V. M. Tiwari, J. Wahr, and S. Swenson, “Dwindling groundwater
resources in northern India, from satellite gravity observations.”
Geophysical Research Letters. vol. 36, L18401. Sep. 17, 2009.
[50] L. Brown, op. cit. [43], pp. 44-48.
[51] D. Rind, R. Goldberg, J. Hansen, C. Rosenzweig, and R. Ruedy,
“Potential evapotranspiration and the likelihood of future droughts,”
Journal of Geophysical Research. 95(D7), pp. 9983-10004. June 20,
1990.
[52] A. Dai, K. E. Trenberth, and T. Qian, "A global dataset of Palmer
Drought Severity Index for 1870-2002: relationship with soil moisture
and effects of surface warming,” Journal of Hydrometeorology. pp 11171130. December 2004.
[53] P. C. Frumhoff, J. J. McCarthy, J. M. Melillo, S. M. Moser, D. J.
Wuebbles, “Confronting climate ghange in the U.S. Northeast: science,
impacts, and solutions.” Cambridge, MA: Union of Concerned Scientists.
Jul. 2007.
[54] K. Hayhoe, J. vanDorn, V. Naik, and D. Wuebbles, “Climate change in
the Midwest: projections of future temperature and precipitation.”
Cambridge, MA: Union of Concerned Scientists. Aug. 2009.
[55] A. Angert, S. Biraud, C. Bonfils, C. C. Henning, W. Buermann, J. Pinzon,
et al., “Drier summers cancel out the CO2 uptake enhancement induced
by warmer springs,” PNAS. 102 (31), pp. 10823-10827. Aug. 2005.
[56] L. H. Allen, Jr., J. T. Baker, and K. J. Boote, “4. The CO2 fertilization
effect: higher carbohydrate production and retention as biomass and seed
yield,” in Global climate change and agricultural production: direct and
indirect effects of changing hydrological, pedological and plant
physiological processes (eds. F. Bazzaz and W. Sombroek) FAO and
John Wiley & Sons. 1996.
[57] J. L. Hatfield, K. J. Boote, B. A. Kimball, L. H. Ziska, R. C. Izaurralde,
D. Ort, et al., Climate impacts on agriculture: implications for crop
production”, Agronomy Journal. 103(2), pp. 351-370. 2011.
[58] M. K. Wali, F. Evrendilek, S. Watts, D. Pant, H. Gibbs, and B. McLead,
“Assessing terrestrial ecosystem sustainability: usefulness of regional
carbon and nitrogen models,” Nature & Resources. 35(4) pp 21-33. Oct.Dec.1999.
[59] L. Brown, “Chapter 4: Rising Temperatures and Rising Seas”, p. 65, in
Plan B: Rescuing a Planet Under Stress and a Civilization in Trouble.
061514
W. W. Norton & Company, New York and London, 2003.
[60] D. B. Lobell and G. P. Asner, “Climate and management contributions to
recent trends in U.S. agricultural yields,” Science. vol 299, p. 1032. Feb.
2003.
[61] K. S. K. Kumar and J. Parikh, “Socio-economic impacts of climate
change on Indian agriculture,” International Review for Environmental
Strategies. 2(2), pp. 277-293. Dec. 2001.
[62] S. Peng, J, Huang, J. E. Sheehy, R. C. Laza, R. M. Visperas, X. Zhong, et
al., “Rice yields decline with higher night temperature from global
warming,” PNAS. 101(27), pp. 9971-9975. July 6, 2004.
[63] D. B. Lobell, W. Schlenker, J. Costa-Roberts, “Climate trends and global
crop production since 1980,” Science. 333(6042), pp. 616-620. July 29,
2011.
[64] W. Schlenker and M. J. Roberts, “Nonlinear temperature effects indicate
severe damages to U.S. crop yields under climate change,” PNAS.
106(27), pp. 15594-15598. Sep. 15, 2009.
[65] C. Müller, A. Bondeau, A. Popp, K. Waha, and M. Fader. “Climate
change impacts on agricultural yields.” Potsdam Institute for Climate
Impact Research. 2009.
[66] FAO: www.fao.org/giews/english/cpfs/index.htm
[67] N. Stern, The Economics of Climate Change: The Stern Review.
Cambridge University Press, Cambridge UK. 705 pp. 2007.
[68] D. M. Catarious Jr., R. Filadelfo, H. Gaffney, S. Maybee, T. Morehouse,
“National security and the threat of climate change,” The CNA
Corporation, Alexandria, VA. Apr. 2007.
[69] C. Jones, J. Lowe, S. Liddicoat and R. Betts, “Committed terrestrial
ecosystem changes due to climate change,” Nature Geoscience. vol. 2,
pp. 484-487. 2009.
[70] P. M. Cox, R. A. Betts, C. D. Jones, S. A. Spall, and I. J. Totterdell,
“Acceleration of global warming due to carbon-cycle feedbacks in a
coupled climate model,” Nature. vol. 408, pp184-187. 2000.
[71] B. Cook, N. Zeng, J. Yoon, “Climatic and ecological future of the
Amazon: likelihood and causes of change,” Earth System Dynamics.
1(1), pp. 63-101. Jan. 2010.
[72] C. Huntingford, R. A. Fisher, L. Mercado, B. B. B. Booth, S. Sitch, P. P.
Harris, “Towards quantifying uncertainty in predictions of Amazon
‘dieback’”, Philosophical Transactions of the Royal Society B.
363(1498), pp1857-1864. May 27, 2008.
[73] R. Fu, L. Yin, We Li, P. A. Arias, R. E. Dickinson, L. Huang, et al.,
“Increased dry-season length over southern Amazonia in recent decades
and its implication for future climate projection,” PNAS. 110(45), pp.
18110-18115. Oct. 21, 2013.
[74] DARA, Climate Vulnerability Monitor: a Guide to the Cold Calculus of a
Hot Planet. Madrid: DARA, Sep. 26, 2012.
[75] A. Freedman, “U.S. Dominated Global Disaster Losses in 2012: Swiss
Re,” Apr. 1, 2013. www.climatecentral.org/news/us-dominated-globaldisaster-losses-in-2012-insurer-reports-15814
[76] P. Watkiss, T. Downing, C. Handley, and R. Butterfield, “The Impacts
and Costs of Climate Change.” European Commission DG Environment.
Sep. 2005.
[77] U.S. Environmental Protection Agency, “EPA Analysis of the American
Power Act in the 111th Congress.” Jun. 14, 2010.
[78] Congressional Budget Office, “Cost Estimate: H.R. 2454, American
Clean Energy and Security Act of 2009.” May 21, 2009
[79] N. Stern, The Economics of Climate Change: The Stern Review [67].
Executive Summary, pp. xiv, xvii
[80] Savory Institute, “Restoring the Climate Through Capture and Storage of
Soil Carbon Through Holistic Planned Grazing.” 2013.
[81] Jim Laurie, personal communication. 2008
[82] Rodale Institute, “Regenerative organic agriculture and climate change: a
down-to-Earth solution to global warming.” Kutztown, PA. 2014.
[83] D. Comis, H. Becker, and K. B. Stelljes, “Depositing carbon in the bank,”
Agricultural Research. 49(2), pp. 4-7. Feb. 2001
[84] P. Smith, H. Haberl, A. Popp, K. Erb, C. Lauk, R. Harper, et al., “How
much land based greenhouse gas mitigation can be achieved without
compromising food security and environmental goals?”, Global Change
Biology. 19(8), pp. 2285-2302. Aug. 2013.
[84] J. Mason, “Understanding the long-term carbon-cycle: weathering of
rocks - a vitally important carbon-sink.” Jul. 2, 2013.
www.skepticalscience.com/weathering.html.
[86] K.S. Lackner, “Climate change: a guide to CO2 sequestration,” Science.
300(5626), pp. 1677-1678. 2003.
[87] http://en.wikipedia.org/wiki/Iron_fertilization
[88] T. Bruckner, I. A. Bashmakov, and Y. Mulugetta, Chapter 7 of Climate
Change 2013: Mitigation of Climate Change. Contribution of Working
Group III to the Fifth Assessment Report of the Intergovernmental Panel
on Climate Change. Cambridge University Press, Cambridge, UK and
8
New York, NY, USA. p. 27
[89] J. W. Raich and K. J. Nadelhoffer, “Belowground carbon allocation in
forest ecosystems: global trends,” Ecology. 70(5), pp. 1346-1354. 1989.
[90] G. Rau, S. A. Carroll, W. L. Bourder, M. J. Singleton, M. M. Smith, and
R. D. Aines, “Direct electrolytic dissolution of silicate minerals for air
CO2 mitigation and carbon-negative H2 production,” PNAS. 110(25), pp.
10095-10100. June 2013.
[91] B. Metz, O. Davidson, H. de Coninck, M. Loos, and L. Meyer (eds.),
Carbon Dioxide Capture and Storage. IPCC Special Report. Feb. 2007.
[92] USDOE/EIA, “Table 7.2a. electricity net generation: total (all sectors),”
Monthly Energy Review.
[93] A. Chen, “New study finds that the price of wind energy in the United
States is near an all-time low,” Lawrence Berkeley Lab. Aug. 6, 2013.
[94] USDOE/EIA, “Table 1. Estimated levelized cost of electricity for new
generation resources, 2019,” Annual Energy Outlook 2014.
[95] USDOE/EIA, “Table 4.3: Existing capacity by energy source,” Electric
Power Annual 2012
[96] Interior Secretary Ken Salazar, remarks at pubic hearing, Atlantic City,
N.J. Apr. 6, 2009.
[97] Z. Shahan, “Solar less than 5¢/kWh in Austin, Texas! (cheaper than
natural gas, coal, & nuclear),” http://cleantechnica.com/2014/03/13/solarsold-less-5¢kwh-austin-texas/. Mar. 13, 2014.
[98] J. Carey and A. Aston, “Solar's day in the sun,” Business Week. Oct. 14,
2007. www.businessweek.com/stories/2007-10-14/solars-day-in-the-sun
[99] T. Mai, R. Wiser, D. Sandor, G. Brinkman, G. Heath, P. Denholm, et al.,
Renewable Electricity Futures Study, vol. 1. National Renewable Energy
Lab, USDOE Office of Energy Efficiency and Renewable Energy. 2012.
[100] “Ice-based technology” in “Thermal energy storage”, http://
en.wikipedia.org/wiki/Thermal_energy_storage.
[101] USDOE/EIA, “Table 1.8: motor vehicle mileage, fuel consumption, and
fuel economy,” Monthly Energy Review.
[102] 2008 mpg: http://en.wikipedia.org/wiki/Fuel_economy_in_automobiles
[103] I. de Carvalho-Macedo, “Greenhouse gas emissions and energy balances
in bio-ethanol production and utilization in Brazil,” Biomass and
Bioenergy. 14(1), pp. 77-81. 1998.
[104] D. Pimentel and T. W. Patzek, “Ethanol production using corn,
switchgrass, and wood; biodiesel production using soybean and
sunflower,” Natural Resources Research. 14(1), pp. 65-76. Mar. 2005.
[105] H. Shapouri and A. McAloon, “The 2001 Net Energy Balance of CornEthanol.” U.S. Department of Agriculture. Jul. 2004.
[106] L. Brown, Full Planet, Empty Plates. New York: W. W. Norton &
Company, 2012, pp. 37-38.
[107] J. Fargione, J. Hill, D. Tilman, S. Polasky, and P. Hawthorne, “Land
clearing and the biofuel carbon debt,” Science. 319(5867), pp. 12351238. Feb. 29, 2008.
[108] T. Searchinger, R. Heimlich, R. A. Houghton, F. Dong, A. Elobeid, J.
Fabiosa, et al., “Use of U.S. croplands for biofuels increases greenhouse
gases through emissions from land-use change,” Science. vol. 319, pp.
1238-1240. Feb. 29, 2008.