CO2 Capture and Sequestration

8/11/2019 CO2 Capture and Sequestration

1/12

Averting Doomsday: An Outlook on

Future Demand for Direct Air Carbon Capture

Alexander Robertson

Spring 2014

It is definitively clear that humanity must reduce or counteract its current rate of carbon dioxide

emissions in order to prevent atmospheric CO2from reaching toxic levels, to avoid the acidification of

Earth's oceans, and to slow worldwide climate change. While we have made encouraging progress in

developing and implementing renewable energy systems, begun to embrace the advent of electric

vehicles, and initiated efforts to develop cleaner power plants, I remain overtly skeptical in regards to our

collective willingness and ability to slow CO2emissions at a pace rapid enough to avoid critical climate

change thresholdsbe it 450 ppm CO2, a 2 C temperature increase, or otherwise. As such, a certain

amount of direct air carbon capture and storage will be imperative if catastrophic, perpetually escalating

impacts on humanity and the global biome are to be avoided, by either finding ways to never surpassdesignated hazardous boundaries or to recover from an overshoot past them. Though this inevitability has

become increasingly acknowledged over the last twenty years, the parameters of the task awaiting us

exactly how much DAC might be required and how many DAC systems might have to be manufactured

and put into useremain relatively uncharacterized.

Split into a three-part dialogue addressing 1) the range of emissions scenarios discussed in the literature

and their environmental implications; 2) the state of DAC technology under development; and 3) the

scope of future DAC necessary to achieve particular atmospheric benchmarks, this paper aims to outline

the goals we should be establishing for integration of DAC into humanity's framework of

environmentally-minded undertakings. By adopting a pessimistic outlook on society's capacity for

limiting year-by-year emissions increasesmy stance is that total annual emissions will not fall belowtoday's level within twenty years and continue to rise for at least that long, with high-carbon centralized

sources persisting for most of the 21stcenturyand treating DAC as an essentiality rather than a last-

resort safety valve, the discussion herein amounts to a depiction of the DAC challenge, both in terms of

the CO2tonnage we must extricate and the amount of DAC systems we should produce over time.

Outlook on Future Societal and Power Plant Emissions

Before delving into air capture itself, let's examine the atmospheric context in which it will be deployed.

For our purposes we will consider only carbon dioxide, as it is currently the predominant climate player

amongst the greenhouse gases and its capture from air has been more extensively studied than CH4andN2O (it should be noted, however, that these cycling of these three gases is interrelated in ways that we do

not yet fully understand and that further unimpeded increases in atmospheric CO2concentrations may

lead to unanticipated consequences involving methane, nitrogen, and the ecological processes involving

each).1First, the utmost basics: since the dawn of the Industrial Era, the juncture beyond which we can

consider anthropogenic emissions to be significant and can generate reliable data characterizing emission

sources, approximately 2100 gigatonnes of CO2have been introduced into the environment due to fossil


2/12

fuel combustion and land use disruptions.1 During this time atmospheric carbon CO2dioxide

concentrations leapt from 278 parts per million to over 400 ppm today.1,10 An increase of this magnitude

in such a short time span is unprecedented over at least the past 22,000 years (and likely much, much

longerwe simply lack avenues of collecting rigorous data further back in Earth's existence); projections

by the International Panel on Climate Change (IPCC) indicate further ppm increases in coming decades,

as can be seen in Figure 1.1

Figure 1:Depiction of past ppm increases and IPCC projection ranges for future levels.

Why is it urgent for us to combat the increasing prevalence of carbon, and what concrete environmental

impacts are associated with continued emissions increases or even with theoretical immediate cessation?

CO2's post-emission pathways result in the carbon problem manifesting itself by air, by land, and by sea.

Proportionally speaking, about half of CO2released into the atmosphere is absorbed by aqueous and

terrestrial sinks within a century (however, increasing saturation of these sinks causes their temporal CO2

uptake capacity to shrink), while the remainder persists in the air for thousands of years.11What are the

broad strokes of the environmental response to elevated carbon content on these three fronts? Air

temperatures rise with radiative forcing intensity, causing glacier melt, heightened erosion rates, a greater

likelihood of forest fires, and dramatic seasonal fluctuations. Atmospheric oxygen levels fall as CO2

concentrations surge. Sea levels rise, ice caps melt away, ocean pH levels drop, and overall marine

temperatures increase while oxygen content declinesposing risks to CaCO3-dependent bottom-dwellers,

their counterparts moving about the water column, and ubiquitous primary producers. Extreme weather

events occur with greater frequency, putting both human lives and our energy infrastructure in danger.2,3


3/12

At this point, the presence of severe ongoing environmental shifts, and humanity's direct role in inducing

them, is beyond dispute. Furthermore, because CO2persists in the dynamic carbon cycle on the order of

millenia before permanently binding to various minerals,and because there exists a lengthy lag phase

between when a ppm level is reached and the time its atmospheric, oceanic, and terrestrial ramifications

are fully realized, we are effectively locked in to further intensifying of these climatic and environmental

transformationseven if today were to be the last day CO2molecules are ever released into theatmosphere.2Exacerbating this actuality is what Dr. Klaus Lackner refers to as "the black swan problem":

there could very well be unforeseen future consequences that acutely intensify the magnitude of overall

environmental harm. The uncharted waters embodied by permafrost and methane hydrate decay is an

example of this: for all our software models and projections and postulations, we simply do not know

with any certainty how these circumstances will play out. Though the black swan line of thinking could

also swing in the opposite direction, towards the notion that Earth will compensate for our misdeeds and

stabilize itself without any assistance, this would be an attitude of complacency and cowardice, and likely

result in future generations ending up in a hole deeper than the one we have already dug for ourselves.

In order for a < 2 C rise beyond 1861-1880 temperatures to be attainable, the post-1880 global emissions

budget is roughly 3670 Gt CO2, and likely less than that after considering probabilistic ranges and

peripheral greenhouse gas factors. We are already more than half of the way to this limit, and emissions

continue to rise at an annual rate of 1-2%.2Considering new and probable upcoming policy changes, we

appear to be heading for a 3.6-5.3 C increase over pre-1750 conditions.5The next international summit

on climate change is scheduled for 2015, but its agreements on emissions policies will not become

binding until 2020.5 The trend of annual CO2output increases is likely to continue until at least that time.

Strides being made by OECD countries in reducing coal-sourced emissions and boosting renewable

energy production are nullified by developing nations' escalating coal usage and ever-growing

transportation sector; this keeps us is in line with the newly direct relationship between CO2and global

GDP over the last ten years.5In 2013 the IEA presented its 4-for-2C proposal, which outlines four steps

that could at least keep us within striking distance of the 450 ppm scenario by the time new internationalmeasures take effect in 2020. While it is encouraging that we theoretically couldadopt these changes and

approach the 450 ppm path, I will not be holding my breath despite the attraction of long-term economic

benefits that supposedly accompany the environmental relief. The proposal relies on energy efficiency

changes for half of its averted emissionsrelying on businesses, homeowners, and individuals to take

unprecedented broad autonomous actionand on coal-fired power plant cutbacks for another improbable

21%.

As Dr. Klaus Lackner discusses in his Carbon Sequestration course at Columbia University, there is a

simple reason that fossil fuels constitute a quality energy source and that humans have become wholly

dependent upon them. The reason? Hydrocarbons are more energy-dense than just about anything else.

An example: over 40 MJ of energy may be drawn from a single kilogram of jet fuel, while our most

advanced batteries contain a relatively meager .5 MJ/kg. This fact (in tandem with research showing that,

in spite of our sincerest efforts to suck the earth dry, there remain massive coal, oil, and natural gas

reserves, containing thousands of gigatonnes of CO2, for the tapping) suggests that there will continue to

be a set of systems and machineryshipping freighters, naval ships, commercial airplanes, fighter jets,

high-performance automobiles, and morewhose demand for hydrocarbons will not dissipate over time,

simply because hydrocarbons are and will continue to be the only fuel source capable of providing


4/12

adequate power within given spatial constraints. Carbon tax and cap-and-trade possibilities, along with

the prospect of clean synthetic liquid fuels, are beyond the scope of this paper, but it is an inevitability

that for as long as there are customers willing to pay for such hydrocarbon-derived energy and the cost of

extracting and processing it remains manageable, enterprising groups will continue to line up to derive

profit from fossil fuel usage. A certain amount of emissions by the aforementioned transport and other

decentralized sources are likely to continue indefinitelyif direct air capture is ever to be the leadingforce in a net-negative emissions scenario, it will first have to neutralize this output before going to work

on extant CO2.7

Green energy has made notable strides over the past couple decades but also seems to have bred a certain

level of false confidence in our capacity for attaining a global society whose electrical and fuel demands

are met by sustainable energy alone. While solar, hydrothermal, and wind energy systems now generate

approximately 20% of our electricity, total anthropogenic emissions are still ascending. According to the

IEA's New Policies Scenario, global electricity usage could increase by over two-thirds between 2011 and

2035, with renewable sources by then providing over 30%. This would be a step in the right direction, and

as of now total renewable energy production is swelling at a pace in line with what is demanded by 2 C

temperature rise scenarios. The catch is that in the grand scheme of things, renewables are still early on in

their development and this rate of growth is likely to prove unsustainable in the long term.5

Pre-combustion capture and flue gas scrubbing, the cousins of direct air capture and themselves an

important tool for battling climate change, are central to potential future reductions in power plant

emissions. The energy sector currently generates two-thirds of global greenhouse emissions. A graphical

breakdown of emission sources is shown in Figure 2. With total energy demand growth projected to

outpace concurrent growth in renewable electricity production, an expanded flue gas CCS program, in

tandem with a continued shift to natural gas and renewable energy, will be integral to reducing emissions

to a level where implementing DAC is sensible. Non-DAC CCS ventures, which encompass carbon

capture in both power generation and industrial settings, are on the rise but not yet proliferating at a ratesufficient to meet the expectations of scenarios on the optimistic end of the IPCC and IEA spectra. 2C

conditions call for annual capture and storage capacity to reach 260 Mt CO2within the next fifteen years,

while we are currently on track for only 65 Mt/year in 2020.5


5/12

Figure 2:Breakdown of fossil fuel CO2emissions by usage category.

Though CO2is much less concentrated in ambient air than in flue gas and other industrial output streams,

thermodynamic analyses suggest that, at a certain threshold, extraction of CO2from the atmosphere is not

considerably more energy-intensive after taking into account the high release temperature and sulfur

content of waste gasses. For flue gas, the upper bound of this regime occurs at 80-90% CO2removal.

Beyond this point, it makes more sense to assign that last 10-20% to DAC. So, even if maximally

effective scrubbers are applied to power plants worldwide, there will continue to be a much-reduced but

steady flow of emissions from the energy sector that will be within DAC's domain for as long as the

carbon cycle remains open and fossil fuel-consuming power plants remain in use.11

Considering the insufficient pace at which we are progressing with a range of CO2emissions reduction

approachesfrom renewable energy to power plant CCS to policy changes to infrastructure and lifestyle

transitionsand recognizing a 1% population growth rate, dozens of terawatts in probable future energy

demand, and increasing emission rates in developing nations, we appear destined to obliterate the 110

tonne per (already alive) person CO2 allowance that would allow for 450 ppm to remain an attainable

target.7

Direct Air Capture: Today's Status & TomorrowsPossibilities

In-depth attention to the climate change issue, with less of the longstanding fascination over the semantics

of the "global warming" concept, seems to be on the risearticles discussing the dire state of the

atmospheric carbon problem have recently been printed in high-profile publications like the New York

Times and the Guardian, and on May 6 the White House released its 2014 National Climate Assessment,

which contains some of the strongest environmental stances (in language at least, if not tangible policy

changes) yet taken by the US federal government. Despite this swelling sense of urgency, awareness of

the current state of DACCS technology, and of its likely crucial role in alleviating the environmental

impact of fossil fuel emissions, remains bafflingly scarce. Representative of this is the complete absence


6/12

of DAC, along with only a passing mention of flue gas CCS treatment, in the National Climate

Assessment's Responses section. It is somewhat logical that a White House-sourced report would be

focused more on political and societal outlooks than on the technological landscape, but this also may

suggest that we continue to lag years behind the carbon problem in terms of realistically assessing its

magnitude and the need to prepare aggressive solutions. Direct air capture is the only theoretical CO2sink

that can be fully separated from all sources, and it would also not be burdened by renewable energysystems' dependence on location and temporality.

While a greater prevalence of government-mandated carbon credits and research funding would help

speed the development and deployment of DAC systems, there are other avenues by which the upfront

economic burden of DAC can be alleviated. Concentrated CO2streams have significant value in both

enhanced oil recovery and greenhouse contexts. Greenhouse growers seeking to improve vegetation

yields and oil companies hoping to wring out their oil fields are willing to pay between $100 and $300 per

ton CO2.7

Implementing DAC for EOR and greenhouse purposes may help speed research, development,

and learning-by-doing progress during these fledgling years. Additionally, enhanced oil recovery's

demonstration of affordable CO2transport and injection is of relevance to the prospect of future large-

scale geological storage, though long-term monitoring of such stores has not yet been sufficiently carried

out. For sequestration by terrestrial injection to be a viable storage method, it must eventually be shown to

permanently confine a high percentage of injected CO2.

Though researchers have made notable strides in the development of direct air carbon capture

technologies, there still persists a wide gap when it comes down to perspectives on the maximal

efficiency and minimal costs of future capture systems. A number of elements must be considered when

evaluating overall system efficiency: the input energy consumed during the capture, release, compression,

and transport of CO2; the physical size of a device relative to its capture volume potential per unit time;

the repeatability of its chemical reaction pathways; and the feasibility of manufacture and installation.

As it stands today, it is clear that the numerous avenues of CO2emission avoidance represent atmosphere-

relief options that are both more economically affordable and easier to implement than direct air capture.

As phrased by Dr. Lackner, to roll out DAC as an emissions combatant at this point would be akin to

trying to steer an aircraft carrier with a tiny wooden rudder. For DAC deployment to be logical, its $/tCO2

capture cost should be less than $/tCO2aversion alternatives. Since even the most optimistic current

estimates of DAC costs are higher than all but the most laborious aversion tactics, this reasoning implies

that large-scale DAC will only become efficacious after emissions from power plants, transport, and

industry have been reduced to a tiny fraction of today's output through a combination of flue gas

scrubbing, energy efficiency adaptations, increased renewable energy production, and other green

efforts.4

That being said, DAC technology should not be abandoned until the possibility of near-zero emissions is

within striking distance. Instead, we should continue to cultivate clean energy systems and pursue every

available emissions-reduction strategy while simultaneously committing serious research work to

optimizing DAC. The longer we delay in doing so, the farther into the 21st century we push the

convergence of CO2aversion and CO2capture costs. The American Physical Society (APS) issued a

direct air capture technology assessment in 2011 which identified the achievable cost of DAC using


7/12

demonstrated approaches to be between $610 and $780 per ton of CO2captured, not including post-

capture transport and storage. Serving as the model for this assessment was a sodium- and calcium-

dependent countercurrent flow system that used fans to drive ambient air over the absorption surface. In

this case, captured CO2was released by heating CaCO3at a thermodynamic cost of 179 kJ/mole.11If this

technology were indeed our most auspicious option, and its predicted costs are accurate, then DAC would

be rendered indefinitely impractical.

Dr. Lackner compares the referenced APS analysis to an attempt at determining whether birds can fly by

studying a penguin. The NaOH-based capture process examined by APS illustrates perhaps the most

critical factor in designing a DAC process: the binding agent must be able to securely extract highly

diffuse CO2from air and then, more importantly, release it at a specified time without a prohibitive

energy input, with energy expenditures also curtailed at every possible juncture throughout the system so

that net CO2uptake is maximized. The APS system did a terrible job of managing energy in these ways.

A device designed by Dr. Lackner instead utilizes amine tethering of CO2by adsorbence and achieves

subsequent freeing of captured gas through a moisture swingCO2is picked up in dry air by resin-coated

surfaces, with a very low requisite flow rate, and released upon exposure to humidity. By eliminating the

need for constant fan activity and high-temperature release conditions without sacrificing low-

concentration CO2extraction capacity, this approach represents a sizable efficiency improvement over the

APS benchmark system. Incorporation of this technology into a device approximately the size of a

standard shipping container could pull a tonne per day of CO2from the atmosphere at a cost $100/tCO2.

David Keith believes a comparable cost could be achieved with his sodium hydroxide process, which

differs significantly from APS's in materials and sequencing.6,7,8,9

With further research, development, and testing in the coming years, we will be able to boost devices'

capture potential and lower their per-tonne costs while both optimizing the most promising contemporary

DAC technologies and experimenting with novel materials and mechanisms that could revolutionize the

next generation of DAC. Nano-patterned panels that maximize contactable surface area and metal organicframeworks may help generate substantial DAC progress, and it is probable that DAC R&D will lead to

flue gas scrubbing advances as well.

Multivariate Models for Direct Air Capture Scaling

So, how much CO2might we need to capture directly from the atmosphere, how many DAC systems

should we imagine manufacturing and operating, and what could the sequence of implementation look

like? The answers to these queries hinge on the extent of future global CO2 emissions, the atmospheric

CO2level we deem to be ideal, the raw capture potential of each DAC unit, and the timeframe within

which we hope to reach our benchmarks.

Constituting the DAC projection framework will be a set of simplifying assumptions and objectives:

1)A conservative performance improvement in DAC technology, by 2035, to 2.5 tons of CO2per day is

used as the baseline extraction rate for a single shipping container-sized DAC unit, with intermediate and

extreme future values of 10 and 25 tCO2/day also addressed.


8/12

2)2200 stands as our deadline for reaching desired CO2ppm levels. The longer we allow the carbon

problem to linger, the more we expose Earth to unforeseeable compounding risks; for all that humanity

has achieved over the last 185 years, it is reasonable to demand from ourselves a competent response to

the carbon problem within an analogous timeframe. The three distinct targets: 450 ppm, the international

consensus threshold for warming of 2 C; 350 ppm, which James Hansen and other researchers consider

to be the upper bound of preventing drastic environmental repercussions; and 280 ppm, the approximatepre-industrial level. Models predict the total number of DAC units needed between 2035, the prospective

DAC initiation date, and 2200, without focusing on the sequence of production scaling.

3)A zoomed-out look at CO2emissions from now until 2200 is adopted. Rather than consider a year-by-

year progression, models consider different values of total anthropogenic emissions between 2014 and

2100 and between 2100 and 2200. 2037 Gt CO2is used as the total emissions value from 1750 through

2011 (555 Gt C multiplied by 3.67 to convert to CO2 tonnage) [IPCC], with an additional 71.25 Gt CO2

cumulatively emitted in 2012 and 2013 [globalcarbonproject.org].

4)Models focus only on capture itself. The intricacies of long-term storage, be it geological, oceanic, or

otherwise, is beyond the scope of this discussion. In any case, a massive amount of storage capacity will

have to become available for large-scale DAC to be viable. Possible leakage rates are also not addressed.

Though leakage will be an important factor for future generations when establishing DAC goals, such "re-

emissions" could be retroactively incorporated into the projections presented here by simply scaling up

the sum-total emissions values used in order to account for the lack of 100% containment.

5)It is assumed that the lifetime of a single DAC unit is 12 years.

Emissions Scenarios: In scenarios I, III, IV, and V, total emissions for up to 2100 correlate with IPCC

Representative Concentration Pathways 2.6, 4.5, 6.0, and 8.5 respectively. 2100 ppm levels used by

CMIP5 simulations to generate each RCP are incorporated into the 2200 ppm values. Though I haveabsolutely zero confidence that we can achieve the emissions demands of RCP2.6, it is included in order

to determine the scope of DAC that would be needed to reach the 350 and 280 ppm benchmarks by 2200

rather than further into the future. Scenario II represents a middle-ground condition between RCP2.6 and

RCP4.5. CO2emissions between 2100 and 2200 are taken to be one-sixth of the respective 2014-2100

values, with the assumption that we will have made headway in eliminating concentrated CO2sources by

2100 but retained some of the relative emission rate discrepancies between scenarios. A summary of

emissions and DAC goals is shown in Figure 3.


9/12

Figure 3:Summary of modeling emissions values and corresponding total DAC needed.

All quantities given in gigatonnes CO2.

Scenario Emissions

2014-2100

Emissions

2100-2200

Emissions

1750-2200

ppm in 2200

w/o DAC

DAC for

450 ppm

DAC for

350 ppm

DAC for

280 ppm

A 1708.75 284.8 4030.5 440.4 -140.9 1327.1 2354.7

B 3130.75 521.8 5689.5 515.5 962.2 2430.2 3457.8C 4552.75 758.8 7348.5 589.7 2050.6 3518.6 4546.2

D 5634.75 939.1 8610.9 734.0 4168.7 5636.7 6664.3

E 8141.75 1357.0 11535.9 1028.4 8491.4 9959.4 10987.0

DAC and Carbon Cycle Dynamics: To account for equilibration between atmosphere, ocean, and land,

it is assumed that 7.34 Gt CO2equates to 1 ppm and that 2 ppm of capture leads to a true atmospheric

reduction of 1 ppm. Thus, 14.68 Gt CO2must be captured and stored to generate a 1 ppm decline.

Because biomass CCS is much more space-intensive than DAC, and because it is plausible that available

land will be primarily dedicated to facilitating increased agricultural output in the face of population

growth, DAC by manmade machinery is treated as the sole atmospheric capture sink.

Figure 4:Total DAC needed by DAC under varying emissions scenarios and ppm objectives.

Discussion and Conclusion: In order to provide a measure of the DAC machinery requirements implied

by each CO2capture goal, the complete set of gigatonne-defined values were translated into unit-years.

One unit-year is equivalent to the annual CO2uptake of an individual DAC system operating at 2.5, 10, or

25 tCO2/day. To draw the atmosphere back down to 450 ppm from RCP8.5-derived Scenario E would

necessitate over 9.3 billion unit-years by 2200 with systems averaging 2.5 tonnes of daily CO2capture. At

a system lifetime of 12 years, this would require upwards of 775.4 million total units produced between

280 ppm

350 ppm

450 ppm


10/12

2035 and 2190. Comparatively, achieving 450 ppm under Scenario B necessitates slightly more than 1

billion unit-years and 87.9 million total units produced during our 165-year capture windowcertainly a

feasible task given our ability to roll over 80 million motor vehicles out of factories each year. If future

DAC advances enable 25 tCO2/day capture rates, then even the drastic emissions condition of Scenario E

becomes manageable at 930.6 million unit-years and 77.5 total units. Meanwhile, Scenarios B, C, and D

would become a relative walk in the park at 8.8, 18.7, and 38.1 million units, respectively. I anticipatehumanity heading somewhere between Scenarios C and D, but with the conceivable development of 10

tonne/day capabilities we would be well-equipped to recover: 46.8 to 95.2 million DAC units could pull

the atmosphere back to 450 ppm. If 350 ppmthe threshold I would like to see us return tois instead

the target, 96.4 to 154.4 million 10 tonne/day units are in order.

Figure 5:DAC unit-years needed to attain 450, 350, or 280 ppm in each emissions

scenario with differing average capture rates by individual units.

Target: 450

ppm in 2200

Unit-Years @

2.5 tCO2/day

Total Units Unit-Years @

10 tCO2/day

Total Units Unit-Years @

25 tCO2/day

Total Units

A 0 0 0 0 0 0

B 1054.5 87.9 263.6 21.2 105.4 8.8

C 2247.3 187.3 561.8 46.8 224.7 18.7

D 4568.5 380.7 1142.1 95.2 456.8 38.1

E 9305.7 775.5 2326.4 193.8 930.6 77.5

Figure 6:Unit-years and total DAC units to reach 450 ppm by 2200 at different capture rates. Values in

millions. Scenario A requires zero DAC because 450 ppm has not been surpassed in 2200.

These results show that with further improvements in technological efficiency and reductions in per-tonne

costs, DAC would serve as a potent tool in solving the atmospheric carbon problem. The extent of scaling

necessary to counteract anthropogenic emissions and either keep CO2below 450 ppm or induce a returnto 350 or 280 ppm is decidedly within our mass manufacturing capabilities, especially if we are able to

boost the capture rates of shipping container-sized devices to 2.5 tCO2/day or higher. Economic

constraints, lack of governmental support, and logical prioritization of other green initiatives will keep

large-scale DAC on the backburner in coming years, but the unit-year and total unit demands calculated

here demonstrate that the urgent fortifying of ongoing R&D efforts could put us in a position to take

environmental destiny into our own hands by the end of the 23rdcentury.


11/12

References

1)

Ciais, P., C. Sabine, G. Bala, L. Bopp, V. Brovkin, J. Canadell, A. Chhabra, R. DeFries, J. Galloway,M. Heimann, C. Jones, C. Le Qur, R.B. Myneni, S. Piao and P. Thornton, 2013: Carbon and OtherBiogeochemical Cycles. In: Climate Change 2013: The Physical Science Basis. Contribution ofWorking Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change[Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V.Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and NewYork, NY, USA.

2)

Collins, M., R. Knutti, J. Arblaster, J.-L. Dufresne, T. Fichefet, P. Friedlingstein, X. Gao, W.J.Gutowski, T. Johns, G. Krinner, M. Shongwe, C. Tebaldi, A.J. Weaver and M. Wehner, 2013: Long-term Climate Change: Projections, Commitments and Irreversibility. In: Climate Change 2013: ThePhysical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of theIntergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K.Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge UniversityPress, Cambridge, United Kingdom and New York, NY, USA.

3)

Cubasch, U., D. Wuebbles, D. Chen, M.C. Facchini, D. Frame, N. Mahowald, and J.-G. Winther,2013: Introduction. In: Climate Change 2013: The Physical Science Basis. Contribution of WorkingGroup I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker,T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex andP.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York,NY, USA.

4)

IPCC (2005).IPCC Special Report on Carbon Dioxide Capture and Storage.Prepared by WorkingGroup III of the Intergovernmental Panel on Climate Change [Metz, B., O. Davidson, H. C. deConinck, M. Loos, and L. A. Meyer (eds.)]. Cambridge University Press, Cambridge, UnitedKingdom and New York, NY, USA, 442 pp.

5)

International Energy Agency Redrawing the Energy-Climate Map. World Energy Outlook SpecialReport. International Energy Agency, Paris, France (2013).

6)

Keith, D., M. Ha-Duong, & J. Stolaroff (2005).Climate Strategy with CO2 Capture from the Air.Climatic Change, 74(1-3): 17-45 doi:10.1007/s10584-005-9026-x.

7)

Lackner, Klaus. Carbon Sequestration Lecture Slides. Columbia University 2014. New York, NY,USA.

8)

Lackner, K.S. (2010)."Washing Carbon out of the Air."Scientific American, June 1, 2010.

9)

Lackner, K.S.Capture of Carbon Dioxide from Ambient Air.Eur. Phys. J. Special Topics,176(1):93-106.

10)

co2now.org

11)

Archer et al.Atmospheric Lifetime of Fossil Fuel Carbon Dioxide. Annu. Rev. Earth Planet. Sci.37:117-34. 2009.
http://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdfhttp://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdfhttp://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdfhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://dx.doi.org/10.1140/epjst/e2009-01150-3http://dx.doi.org/10.1140/epjst/e2009-01150-3http://dx.doi.org/10.1140/epjst/e2009-01150-3http://dx.doi.org/10.1140/epjst/e2009-01150-3http://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdf


12/12

12)

APS (2011). Direct Air Capture of CO2 with Chemicals.

CO2 Capture and Sequestration

Documents

Transcript of CO2 Capture and Sequestration