Incapacitating Atmospheric Greenhouse Gases25 min read
This is an outline of our Bounce Back ground initiative. Under it, we work towards building a system that incapacitates atmospheric greenhouse gases and allows for the attenuation of their combined global warming impact. That system must not compromise terrestrial and marine ecosystems.
Read about our other ground initiative Super Powers here. Under it, we aspire to create an industrial apparatus for high-capacity, low-risk generation of electrical power.
The primary goal we are pursuing with Bounce Back is not hard to understand, and its significance in the context of climate change is evident: We want to provide for a system that downregulates the global warming response to the accumulation of greenhouse gases in the atmosphere.
Inhibiting the heat-trapping capacity of atmospheric greenhouse gases helps to bounce back from the level of global warming to which we are currently committed by virtue of past emissions. The inhibitive effect must equate to reversing atmospheric greenhouse gas-concentrations to pre-industrial levels, whether greenhouse gas molecules are effectively removed from the atmosphere or not.
In contrast to our Super Powers ground initiative, where we put two technologies up for discussion (nuclear fusion reactors and liquid fluoride thorium reactors), we were incapable of coming up with more than one sound idea on how to Bounce Back on global warming by means of inhibiting greenhouse gases. And the idea being a sound one might already be an exaggeration in light of our aspiration to only pursue what makes sense from both the perspective of holism and essentiality.
That is why Bounce Back is in demand of some individuals that are both smart enough and bold in character for collectively creating a viable approach. As we will outline below, we are confident that the incapacitation of atmospheric greenhouse gases is a very promising concept for downregulating global warming, but we are unsure of how to make it happen.
Hence, we invite anyone with an impartial and qualified predilection for our cause to weigh in on examining alternative strategies to contain the rise of our planet’s temperatures.
Bouncing Back from CO2 Overload
What Do Greenhouse Gases Actually Do?
Greenhouse gases exert their warming potential by increasing the amount of solar radiative energy that is contained within the system of the earth.
When the planet’s surface re-emits energy it received from the sun, it does so by radiating electromagnetic waves. All of these outgoing waves are in the infrared spectrum. Radiant energy that comes in the form of infrared-length waves can be absorbed by some of the gas molecules that occur in the atmosphere.
To be susceptible to an electromagnetic wave, the atomic bonds of a molecule must vibrate at a frequency that corresponds with the frequency of the excitatory wave, and it must present an asymmetrical distribution of electrical charges (a dipole moment) for the wave being able to release its energy onto the molecule. With the wave exerting varying levels of force to the unevenly charged poles of the recipient molecule, the vibrational amplitude of the molecular bonds is increased, which corresponds to a transition to a higher energy level. Effectively, the molecule has absorbed the energy that came with the wave.
As it turns out, gases that have more than two atoms, like CO2, CH4, and N2O, are configured in a way as to present perfect asymmetries of electrical charges, and they vibrate at frequencies that match the spectrum of terrestrial radiation in large parts. Hence, they are very well suited to absorb radiant energy that has been emitted by Earth (while gases that cannot present a dipole moment, like O2 or N2, are not).
Then, similar to the earth re-emitting some of the solar radiation, these atmospheric molecules re-emit some of the absorbed terrestrial radiation themselves. Part of that re-emittance is directed towards space and another part is directed back towards the earth. One could say that half the terrestrial radiative energy rebounds off the atmosphere and gets reflected back to Earth. By repeatedly mirroring radiative energy that would otherwise have disappeared into space—never to be seen again&mdashthese gases trap heat within the confines of planet Earth. That is why they are called greenhouse gases, and the entire process of absorption and mirroring is called the greenhouse effect. In essence, what greenhouse gases actually do is to increase the difference between the earth-bound radiance and the space-bound radiance. They exert what is called “radiative forcing” and that forcing is what leads to warming.
Some of that forcing is good though. With no greenhouse effect at all, almost all the terrestrial radiation would escape into space, and the earth would turn into a gigantic snowball. But too much absorption and mirroring resulting from excessive levels of greenhouse gases in the atmosphere warms the planet to a degree that might become irreconcilable with human life.
Incapacitation: Unfanciful or the Edgy Way
So, for cooling the earth (or at least limit further warming), one feasible approach is to weaken the collateral radiative forcing exerted through greenhouse gases that have excessively accumulated in the atmosphere, or to eliminate that surplus forcing altogether. Fundamentally, such mitigation requires stripping the forcing agents of their heat-trapping capacity—by whatever means.
Atmospheric forcing agents can be incapacitated in a variety of ways with simple “catch-and-bury”-style removal being an unfanciful but sure bet. While we do not mean to preclude any other forms of incapacitation, in the following outline, we concentrate on the straightforward removal of greenhouse gases from ambient air. Admittedly, it is a rather crude way to solve the problem of excess radiative forcing. But in contrast to some ideas relating to more subtle means of incapacitation, “catch-and-bury” is what is already practiced—albeit at pilot-scales only. And then, our ignorance towards more decent choices also reflects our present lack of knowledge regarding those means of incapacitation, which remained true to our fundamental credo of not jeopardizing the integrity of terrestrial and marine ecosystems.
By means of example, allow us to inject just one potentially crazy idea here that captures well what we mean by “more decent”. After all, at Archai we count on ideas coming from the most unexpected of places to come up with truly creative solutions.
That hypothesis builds on acting upon the heat-trapping substance in an almost surgical manner. Specifically, we think that changing or interfering with the configuration of bonds between the atoms comprising a greenhouse gas might comply with the fundamental requirement of stripping these molecules of their heat-trapping capacity.
In theory, directly targeting the compound that causes global warming or, more precisely, interfering with its potential to absorb energy in the form of electromagnetic radiation makes perfect sense. If we could restrict or at least attenuate the transfer of energy from an electromagnetic wave to a greenhouse gas molecule, we could enlargen what is called the atmospheric window. That window describes those bands of wavelengths, at which the corresponding electromagnetic waves simply pass through the atmosphere because their frequencies do not match any of the excitation frequencies needed to make one of the greenhouse gases react to their impinging. If the number of wave-to-molecule energy-transfers was reduced, the atmosphere essentially became more transmissive to terrestrial radiation, lowering the heat trapped within the confines of the planet.
Let us make this proposal even edgier by going into some more detail. Interference with a molecule’s capacity to absorb energy could take place in a variety of ways. One could be to modify the recipient, the gas molecule that is. For example, CO2 lives in three distinct vibrational modes with only two of them being relevant with regard to the greenhouse effect. Would it be possible to force some molecules living in the “bad vibrational mode” to assume the harmless one? Another way could be to engage with the “medium” to be absorbed by the recipient. What if we could modulate the frequency at which the earth radiates energy? With a (partial) mismatch between that frequency and the vibrational frequency of the greenhouse gas molecules, the latter would be hampered in their ability to absorb energy. Of course, we must be wary not to build a “modulator machine” that consumes more energy than it is capable of smuggling across the atmosphere. Being laymen in these matters, we reach out to the physicists, and the chemists, and the mathematicians, and the power engineers, and the radio mechanics, and the gardeners, the nurses, the construction workers, and the graduate students for finding an answer to these questions. Collectively they will find a way!
CO2 Makes a Dominant Contribution to Global Warming
Thinking in more conventional terms again and elaborating further on the option of removing greenhouse gases from ambient air, we suggest focussing on the removal of CO2, although we do not imply that other greenhouse gases do not lend themselves to some form of forcing-suspension. We do so, knowing that CO2 is just one in a long list of climate-active agents. In terms of global warming potential (GWP), a measure that came to be some official standard for indicating the climate-impact of different gases, it is not even a very potent one compared to other greenhouse gases such as methane (CH4) or nitrous oxide (N2O). The GWP is an expression of the amount of radiative forcing accumulated over a given period for a particular gas compared to CO2 on a like-for-like basis regarding weight (e.g., the time-integrated forcing of 1 kilogram of CH4 is compared to the forcing exerted by 1 kilogram of CO2).
However, to identify the gas that occupies the highest potential for causing harm, emission volumes must be part of the equation.
Because a GWP-calculation entails the radiative efficiency of the gas in question (as well as carbon dioxide, serving as the reference gas), the non-linear relation between the atmospheric concentration of some gases and their radiative efficiency suggests that future emission scenarios would be an even better indicator than current emissions as to the potential harmfulness of a gas. (For those raising their hand here to point to the fact that atmospheric lifetimes of different gases must not be dismissed, we point to this introduction into the concept of GWP explaining the mechanism by which a gas’ time-dependent decay factors into the GWP calculation.) But these scenarios are highly speculative. Also, in anticipation of the emissions mix effectively remaining unchanged over the timeframe that might be considered relevant when it comes to our ability to willfully avoid the climate catastrophe (maybe that is ten years), we rely on current emission levels being a suitable factor to accompany the GWP-indication in serving as a compound proxy to a greenhouse gas’ adverse effect.
When we take emission levels into account, comparative climate-potencies for different gases are dramatically altered compared to what GWPs alone insinuate. It becomes evident that CO2 is a massively impactful greenhouse gas. By way of example, even with the compound radiative forcing of 1 kilogram of CH4 over a 100-year period corresponding to the forcing exerted by a one-time blast of 28 kilograms of CO2 over the same period (for a time horizon of 100 years CH4 has a GWP of 28), the vast abundance of CO2 in the global emissions-mix overcompensates for that inferior warming potential. This becomes evident when looking at emission volumes of different greenhouse gases measured as carbon dioxide equivalencies (CO2eq). The measurement unit of CO2eq merges the two measures of GWP and absolute emission volumes into one to allow for a compound assessment of for the climate-impact of a gas. Put differently, CO2eq allows for comparing absolute emission volumes of different greenhouse gases given their GWPs. However described, CO2eq indicates the harmfulness of a greenhouse gas and current estimates show that carbon dioxide indeed makes a dominant contribution to total global warming. Compared to CH4, which accounts for 16 percent of global greenhouse gas emissions (measured as CO2eq), CO2 accounts for 76 percent (estimation for the year 2010; IPCC AR5, WGIII, Fig. 1.3). All of that emitted carbon dioxide eventually shows up in the atmosphere where it unfolds its warming potential.
We Need to Push CO2 Back to Where It Came From
The primary purpose of any carbon dioxide removal initiative must then be to push some carbon of geological origin back to where it came from before humans started extracting and burning it in the fossil fuel-driven era of the Industrial Age. Mostly, it is the perturbations in the carbon cycle that took place from about the year 1750 that must be reversed now. The argument behind is very straightforward: Carbon that rests in rocks has no climate impact, while carbon that freewheels through non-geologic reservoirs and eventually accumulates in the atmosphere causes the entire mess.
From a biogeochemical perspective, the full carbon cycle may be viewed as consisting of two intertwined domains (for a detailed description of the carbon cycle and its two domains see the IPCC AR5, WGI, Chapter 6, page 470ff.). One domain comprises the fluxes among non-geologic carbon reservoirs such as the ocean, surface ocean sediments, land vegetation, soils, freshwater, and the atmosphere. These fluxes are characterized by their relative speed and vast quantities of CO2 being turned over. As a result, the respective reservoirs experience rapid turnover times. In contrast to these rapid-turnover-pools, substantial geologic carbon stores in rocks and sediments are characterized by slow exchange fluxes. These geologic stores comprise the other domain. It is through chemical weathering, erosion, and the formation of sediments on the sea floor that the rapid domain inserts into the slow domain, and it is through volcanic eruptions or by pumping refined crude oil into the fuel tanks of our vehicles that the slow domain impinges upon the rapid domain.
Atmospheric CO2 is a component of the rapid domain. However, with the reversal of past CO2 emissions in mind, we will have to put our attention to both the rapid and the slow domains. It is from the rapid domain that we must abstract the gas and it is the slow domain into which we must feed it. The ultimate goal is then to accelerate the rehabilitation of geologic carbon stores. More specifically, we must enhance the transfer of CO2 from the atmosphere to disposal sites in rocks or sediments. Such permanent clearance would effectively result in the restoration of a lower-level steady state of the carbon cycle’s rapid domain which can be declared the summum bonum (the supreme good from which all others are derived) for climate change mitigation—and even reversal—without argument.
Accordingly, we advocate that carbon dioxide removal from ambient air be part of any solution for sustaining an Enjoyable Planet Earth. When such removal is complemented with permanent decoupling of atmospheric CO2 from the carbon cycle’s rapid domain by feeding the gas back into the cycle’s slow domain, we run a chance of avoiding global warming levels that would bring about more severe upheaval and social unrest than what we already see today.
Direct Air Capture and Refinement Framework
We Are Incapable of Exhibiting a Real Solution
In the following, we present what comes closest to a solution for satisfying the stated goals of the Bounce Back ground initiative. Specifically, we propose the development and deployment of a Direct Air Capture and Refinement Framework (DAC-RF). As you will see, DAC-RF is barely more than what the word framework implies. It is a skeleton or a conceptual structure much more than it is a real solution for bringing the Bounce Back initiative into being.
The final framework must eventually entail the technical blueprint based on which the equipment needed for large-scale reversal of past greenhouse gas perturbations and a roll-back of current levels of global warming will ultimately be built. To supplement this engineered core, the framework must be furnished with an economic model for implementation and operation and with an outline of how to effectively navigate the political landscape and other potentially obstructive forces of the social domain. Currently, we are incapable of coming up with tangible details on either of these elements of a formative layout grid.
Owing to the experience of those that are already invested in variants of carbon capture technologies, we think that the economic model commands extra close attention. Without substantial monetary incentives to cut back on carbon emissions, no private actor will expedite the build-up of large-scale infrastructure—and a public actor accountable to tax-payers will not either. So, unless we come to grips with imposing a tax on carbon emissions or rewarding the inhibition of emissions (through a scheme like cap-and-trade), there must be a way for the system to pay for itself, and maybe even generate a profit. That is where the refinement portion of the framework comes into play. By it, we simply mean figuring out a way of turning a fraction of the captured carbon into something of value.
Conventional Carbon Capture and Storage Is Really Stupid
We want to emphasize that DAC-RF is distinctly different from technological systems known as Carbon Capture and Storage (conventionally referred to as CCS). CCS-technologies mostly facilitate the collection of CO2 emitted from large point sources (such as the smokestacks of coal-fired power plants) while being ineffective when it comes to harvesting CO2 that originates from mobile or highly dispersed flue pipes and chimneys (such as those of cars and residential buildings). We advocate the concept of capturing CO2 from ambient air, that is the scrubbing of the gas from the atmosphere (meaning to involve everything from the Earth’s ground up to the top of the uppermost boundary of these layers of gases) with no necessary affiliation to a carbon source.
Conventional CCS misses out on at least half of current emissions (those from dispersed sources) while collecting carbon from ambient air is responsive to emissions from any source. Even worse, CCS leaves past emissions completely untouched. In contrast, DAC-RF is also concerned with those CO2-molecules that have gone about their heat-trapping business for many years and will continue to do so without deliberate intervention. And then there is the troubling fact that CCS might become a remedy for the poor souls whose only fear it is that fossil-fueled power generation might come to an end. Hence, CCS is really stupid in many ways.
Smart Alternatives to Heavy Machinery Are in Demand
While thinking that conventional CCS is stupid, we also believe that some technologies to capture carbon from ambient air are pointing in the right way, but are still amenable to some smart enhancements.
By “Direct Air Capture” (DAC) of CO2 from ambient air, we do not necessarily mean scrubbing the gas from the atmosphere by sucking air into a huge machine and pushing it through CO2-sequestering devices. That solution (which represents the somewhat narrow interpretation of DAC facilitated by those who are currently focusing on these air-sucking devices) comes with a massive upfront investment into capturing capacities and even with a fair amount of money put into it, the progress might prove to be too minuscule for the emerging infrastructure to gain the upper hand on the installed as well as the naturally occurring emission capacities. If you think of all the oil rigs and gas production facilities, the installations used for transportation, the refineries, the distribution networks and the units of final consumption, it took a an armada of industrial facilities to put the carbon into the air (and this is not yet incorporating the natural facilities of carbon emission or any manmade installations other than the ones comprising the fossil fuel value chain). If we aim at counteracting this engine with its equals, namely with heavy machinery, it will cost a lot (maybe too much), and it will take a long time until completion (maybe too long). While some of these air-sucking machines are already capturing carbon from ambient air (made possible by private companies like ClimeWorks and Carbon Engineering), the entire concept might turn out to be just part of a solution rather than a solution in its own right.
The argumentation goes almost along the same lines with another net-negative emission technology. Employing “Bio-Energy with Carbon Capturing and Sequestration” (BECCS) involves scrubbing of CO2 from ambient air by means of plants that turn the greenhouse gas into biomass (and oxygen) and operating power plants that are fueled with that biomass and also equipped with the technical components to capture CO2 from the exhaust. That way, carbon is captured from the atmosphere at decentralized locations with an enormously potent machinery (the surface of photosynthetically active organisms is huge, especially if we also account for those organisms that live in marine ecosystems) while the process of scraping out and collecting carbon is centralized and, thus, can be supplied with an exhaust fume that is heavily saturated with CO2 (making the entire process much more efficient). Admittedly, BECCS is a laborious way of capturing CO2, just as direct air capturing by means of air-sucking machines is. In contrast to the latter, however, BECCS potentially offers the advantage of not being contingent upon “new-to-be-installed” infrastructure. Existing power plants can be converted to operate on biomass, and they can also be retrofitted with the components that allow for the collection of CO2 from the exhaust. But then again, it is still a machine- and, consequently, capital-heavy undertaking.
What we probably need is a really smart alternative to heavy machinery. We must engage in finding other, more ingenious ways for directly capturing emitted carbon dioxide from ambient air. Uncompromising ideation and scientific research should be capable of delivering on that aspiration.
At present, however, no concept is convincing enough to help the underlying technology unfold on an enormous scale. Some lack economic viability like all those flavors of heavy-machine-based carbon capturing addressed above, and some carry substantial risks because of their heavy interference with terrestrial or marine ecosystems (like enhanced weathering or ocean fertilization).
The refinement part of DAC-RF might turn out to be quite a hassle too. In that regard, we encourage the investigation of processing technologies for turning worthless CO2 into something valuable instead of just dumping carbon into geologic reservoirs. As long as there is no charge for pumping CO2 into the air, there will be no economically viable model for deploying and operating a carbon-capturing device. Monetizing on captured CO2 through refinement at least offers a chance to pay for the capturing operation and maybe even for secure disposal of excess carbon that has not been refined. If things go really well the chance to make a profit may arise. This, naturally, would put an entirely new complexion to the aspiration.
Holism Is Hard to Satisfy by DAC-RF
DAC-RFs do not obey very well the principles inferred from holism. In fact, such a framework is bound to come under attack from the forces of reality from multiple sides. Regarding the physical domain of these forces, a handful of engineered and deployed installations that are capable of picking out CO2 molecules from a stream of air show that some techniques for direct capture are fit for use. Working at pilot scales, however, these devices do not prove more than the gas being separable from the air it is carried by in larger than laboratory quantities.
However, efficiencies are very poor. The energy required to single-out CO2 molecules and turn the carbon-component into a substrate for further processing is huge. Given a global system for energy supply that relies on fossil fuels, the energy-intensive operation of devices that are built to collect carbon and provide for negative emissions may even turn into a net-positive emission venture. Even if powered by a renewable source of energy, one might argue that the consumption of clean energy by a DAC-RF device prevents another energy consumer from using that same clean energy. As a consequence, that left out consumer is redirected to being supplied by a carbon-emitting power source. One way or another, the low capture-and-sequester efficiencies of many present-day direct air capture modules render them carbon-neutral at best.
At the societal front of the forces of reality, the picture is not much brighter. Two issues currently undermine large-scale deployment: lack of economic viability and societal repugnance. Irrespective of the technological approach, every installation required to catch hold somehow of thinly dispersed airborne CO2 molecules is going to be massive. Above, we have already touched upon the fact that the deployment of such a structure will be immensely capital-intensive as a consequence. For every investor, private or public, such a capital expenditure has to pay back over time. With no price tag on emitted CO2 and with no reward-scheme in place for omitting emissions, the economies of such an operation must be geared up by refining some of the captured carbon into a commercial product that is going to pay for investments and running cost.
Here comes some delight: As it turns out, there are more than a few possible uses of CO2. For example, the molecule and its derivatives can be manufactured into synthetic fuels, it can be converted into fertilizers, used as a gas in industry and food processing, and it may be used to produce building materials. CO2-bound carbon might also potentially be molded into graphite. All of the before listed end-products are of some value. At least, each one is more valuable than its source material, and gross margins of some of these operations seem to contribute to the cost of their respective entire value chain, as some real-world ventures claim (for more on how to profitably capturing atmospheric CO2 by feeding it into a variety of industrial value chains see Graciela Chichilnisky of Global Thermostat, speech held at AREDAY 2016).
But even with a procedure for transforming a portion of the captured carbon into something useful in place, societal repugnance might arise from pumping the non-refined and non-sellable fraction into geological reservoirs. Today, the general population is immensely concerned with the long-term security of such sites for permanent disposal, and it is anxious about the potential harm terrestrial ecosystems or geological structures might experience.
For all of the above, measured against the principles inferred from holism, DAC-RFs must clear some bulky obstacles out of the way—obstacles in terms of both the physical potency of the underlying technologies and their proper embedding into social mechanisms.
Essentiality Is a Given—in Principle
DAC-RFs are a fantastic idea that harbors the potential of truly becoming the summum bonum for sustaining an Enjoyable Planet Earth. Any device—or system rather—providing for net-negative emissions entails the promise of finally eluding the experience of detrimental climate change. In its Fifth Assessment Report, the IPCC stipulates the need for large-scale adoption of carbon dioxide removal technologies in a majority of climate scenarios assessed with a 66% or higher chance of limiting global warming to 2 degrees Celsius by the year 2100. What makes these technologies so compelling is their ability to deprive CO2 molecules of both future and past emissions of their heat-trapping capacity. With no hesitation, we attest to the concept of DAC-RF (and also other direct air capture systems) taking on an essential role in any script for mitigating climate change—in principle, we must add.
The positive, yet latent, outlook on essentiality must now evolve into actual technical applications that withstand all of the counteracting forces of reality depicted above. And that is a very long shot! Even though we can observe the emergence of mini-plants covering a broad range of available technologies, none of these have proven to be scalable. Regardless of the assertive voices purporting the advent of rapidly declining costs for many of the assets required to perform direct air capture, the economic realities persist. With no operating model in place that allows to churn out assets with a real market value from the process, those assets that come with a cost will cripple all ambitions to scale-up.
In light of all the ambiguities surrounding direct air capture, and in particular with an eye on the economic deficiencies, we call for the investigation of opportunities for carbon refinement to be enhanced drastically and we push for an unbiased discussion to identify the most promising way of capturing carbon from ambient air. The goal must be to come to a conclusion—time for pondering is up!
What Is More?
Maybe there is an entirely new approach to be developed for incapacitating greenhouse gases—one that does not rely on painstakingly secluding single molecules from a medium of the sheer size of the atmosphere. You are very welcome to reach out to us in case you think that this is the case. And, sure enough, you are also welcome to invest yourself in developing scalable and economically viable technologies on the DAC-RF frontier.
No matter how extravagant your idea might be, if you beware of arguing in a dogmatic manner, we will always get back to you. So let us hear your arguments.
More of Climate Change
This is an outline of our Super Powers ground initiative. Under it, we aspire to create an industrial apparatus for high-capacity, low-risk generation of electrical power. That power must be supplied in a constant (that is, non-intermittent), and carbon-neutral manner.
The primary goal we are pursuing with Super Powers is not hard to understand, and its significance in the context of climate change is evident: We want to provide for a massively potent source of electrical power that does not add to the accumulation of greenhouse gases in the atmosphere.