Direct Air Capture (Technology Factsheet)


Direct Air Capture (DAC) is a largely theoretical technique in which CO2 (and potentially other greenhouse gases) are removed directly from the atmosphere. The current technique uses large fans that move ambient air through a filter, using a chemical adsorbent to produce a pure CO2 stream that could be stored. To have any significant effect on global CO2 concentrations, DAC would need to be rolled out on a vast scale, raising serious questions about the energy it requires, the levels of water usage for particular technologies, and the toxicity impacts from the chemical sorbents used. In addition, safe and long-term CO2 storage cannot be guaranteed, either in geological formations where leakage is a risk (see CCS factsheet1) or in products using CO2, where carbon is likely to end up back in the atmosphere one way or another (see CCUS factsheet2). The fossil fuel industry is attracted to DAC because the captured CO2 can be used to for Enhanced Oil Recovery (EOR), especially where there is not enough commercial CO2 available locally.

At a DAC summit in Calgary in 2012 there were a number of oil companies in attendance, including Suncor, BP, Husky Oil, and Nexen

Actors involved

DAC is a commercially active geoengineering technology. David Keith’s company Carbon Engineering is funded by private investors including Bill Gates and Murray Edwards, the billionaire tar sands magnate who runs Canadian Natural Resources Ltd (Keith is a prominent US-based geoengineering researcher and proponent). Carbon Engineering opened an CAD$ 8 million pilot plant in Squamish, British Columbia in 2015, where they claim to extract about a tonne of carbon dioxide a day.3 Carbon Engineering also plans to turn captured CO2 into transport fuels, which then re-emit CO2 into the atmosphere when they are burned.4

Swiss company Climeworks says they have created the “first commercial plant to capture CO2 from air” in Zurich.5 They claim the US$ 23 million plant is supplying 900 tonnes of CO2 annually to a nearby greenhouse to help grow vegetables. They have partnered in Iceland with Reykjavik Energy at the Hellisheidi geothermal plant to run one of their air capture units (with capacity to capture 50 tonnes of CO2 per year) and inject CO2 into basalt formations. This project, CarbFix2, has received funding from the European Union’s Horizon 2020 research and innovation programme.6 Reykjavik Energy, and in particular the Hellisheidi geothermal plant, have been the focus of large-scale environmental protests in Iceland for causing serious harm in what is Europe’s last remaining area of wilderness.7

Other companies developing DAC include Global Thermostat, bankrolled by Goldman Sachs, and partnered with Algae Systems,8 as well as Skytree in the Netherlands and Infinitree (formerly Kilimanjaro) in the US.9

David Keith and other developers have pitched DAC as a means to use captured CO2 to massively scale up the EOR industry in the US and elsewhere. At a DAC summit in Calgary in 2012 there were a number of oil companies in attendance, including Suncor, BP, Husky Oil, and Nexen.10 However, optimism for DAC’s business case is belied by the reality that it is not economically feasible due to high costs,11 which are likely to be more than 4 times greater than other Carbon Dioxide Removal approaches.12 Moreover, using DAC to enable EOR would obviously cancel any supposed climate mitigation benefits.13

DAC technology has attracted the attention of venture capitalists like Ned David, who is keen on EOR and runs an algae synthetic biology company. He hopes to create biofuels by feeding captured carbon to algae produced in giant vats outdoors and has sought funding from Monsanto.14

Direct Air Capture would be likely be used for Enhanced Oil Recovery, and would incur significant energy costs and divert resources from alternative energy sources. There would also be a significant risk of the CO2 leaking back into the atmosphere, potentially causing ecological damage.


DAC requires considerable energy input. When including energy inputs for mining, processing, transport and injection, energy requirements are greater still, perhaps as much as 45 gigajoules per tonne of CO2 extracted.15 For David Keith’s pilot DAC unit, this is the equivalent of running it off a constant 0.5 megawatt power supply.16 Neither Climateworks nor Carbon Engineering publish the energy requirements of their units, and in the case of Carbon Engineering, it is not known how the electricity powering the unit is produced. Because of the huge demand for energy that DAC implies, some geoengineering promoters have proposed to use “small nuclear power plants” connected to DAC installations, 17 potentially introducing a whole new set of environmental impacts.

DAC also requires substantial water input. One study estimates that at implementation levels that would remove 3.3 gigatonnes of carbon per year, DAC could expect to use around 300 km3 of water per year (assuming current amine technology, which is what Climeworks uses). This is equivalent to 4% of the water used for crop cultivation each year. DAC technologies using sodium hydroxide (Carbon Engineering) would use far less,18 but this in turn is a highly caustic and dangerous substance.

Washington State Governor Jay Inslee inspects a Climeworks DAC unit in Switzerland (Jay Inslee/Creative Commons)

A modelling exercise looking at the impact of DAC on climate stabilization efforts predicted that it would postpone the timing of mitigation (emissions reductions) and allow for a prolonged use of oil, impacting positively on energy exporting countries.19 This is of course similar for many geoengineering technologies and one of their most dangerous aspects.

Reality check

There is one demonstration facility near Zurich owned by Climeworks,20 and another by the same company in Iceland.21 Carbon Engineering also operates a pilot plant in British Columbia.22 In addition there are several companies that have developed small-scale capture units, with numerous research projects also underway.

Further reading

ETC Group and Heinrich Böll Foundation, “Geoengineering Map.”

The Big Bad Fix: The Case Against Climate Geoengineering,


1. See Geoengineering Monitor, “Carbon Capture and Storage,” Technology Fact Sheet, April 2018.

2. See Geoengineering Monitor, “Carbon Capture, Use and Storage,” Technology Fact Sheet, April 2018.

3. John Lehmann, “Could this plant hold the key to generating fuel from CO2 emissions?” The Globe and Mail, 2017,

4. Carbon Engineering, “Carbon to fuels,”

5. Alister Doyle, “Scientists dim sunlight, suck up carbon dioxide to cool planet,” Reuters, 2017,

6. ClimeWorks, “Climeworks and CarbFix2: The world’s first carbon removal solution through direct air capture,” 2017,

7. Saving Iceland, “Hellisheidi: a geothermal embarrassment,” 2017,

8. Algae Systems, 2017,

9. Infinitree, “Carbon Capture Greenhouse Enrichment,” 2017,

10. Marc Gunther, “The business of cooling the planet,” Fortune, 2011,

11. Marc Gunther, “Direct air carbon capture: Oil’s answer to fracking?” GreenBiz, 2012,

12. Derek Martin et al., “Carbon Dioxide Removal Options: A Literature Review Identifying Carbon Removal Potentials and Costs,” University of Michigan, 2017

13. Marc Gunther, 2012,

14. Katie Fehrenbacher, “Algae startup Sapphire Energy raising $144M,” Gigaom, 2012,

15. Pete Smith et al., “Biophysical and economic limits to negative CO2 emissions,” Nature Climate Change, 2015

16. W=J/t, therefore 45GJ / 1 day in seconds = roughly 500,000W

17. Proposed by David Sevier, Carbon Cycle Limited, UK; communication in a geoengineering electronic discussion group, September 2017

18. Pete Smith et al., 2015

19. Chen Chen and Massimo Tavoni, “Direct air capture of CO2 and climate stabilization: A model based assessment,” Climatic Change, Vol. 118, 2013, pp. 59–72

20. Christa Marshall, “In Switzerland, a giant new machine is sucking carbon directly from the air,” Science,  2017,

21. ClimeWorks, “Public Update on CarbFix,” 2017,

22. John Lehmann, 2017

Carbon Capture Use and Storage (Technology Factsheet)

In theory, Carbon Capture Use and Stoage aims to convert captured carbon into products like fuel, fertilizer and plastic.


Carbon Capture Use and Storage (CCUS) is a proposal to commodify CO2 that has been removed from the atmosphere by using it as a feedstock in manufacturing, so it becomes “stored” in manufactured goods. It is understood as an attempt to make CCS profitable and perhaps uncouple it from Enhanced Oil Recovery (See Carbon Capture and Storage (CCS) briefing for more background on this). Some CCUS scenarios are still theoretical and some technologies are being commercialized.

The primary critique of CCUS is that emissions are not effectively removed or sequestered but are embedded in products or used in a way that CO2 will be re-released into the atmosphere (it will be incinerated as waste or decompose). There are also additional emissions in the production, transport and infrastructure required. This means that overall, CCUS is likely to create emissions rather than reduce them.

Enhanced Oil Recovery (EOR)

While CCUS is an attempt to distance CCS from EOR, EOR is by far the single biggest user of captured CO2 and the most likely profitable market for it in the future. EOR is discussed in more detail in the CCS factsheet. Briefly, EOR refers to extracting otherwise unrecoverable oil reserves. CO2 is injected into aging reservoirs and can extract 30–60% more of the oil originally available in the well. Naturally-occurring CO2 is used most commonly because it is cheap and widely available, but CO2 from anthropogenic sources is becoming more common,i particularly from CCS installations in North America.

For example, of 17 operational, commercial-scale CCS facilities world-wide, 13 of them send their captured CO2 for use in EOR, and of the four facilities listed as being under construction, three are for EOR.ii In this case, EOR in is certainly Carbon Capture and Use, but it is not Storage: most CO2 returns back to the surface with the pumped oil, and any CO2 that does stay underground enables even greater emissions from the extra oil that is pumped out and then burned.iii

Turning CO2 into chemicals and fuels

Another idea is to use CO2 by processing and converting it into chemicals and fuels. This can be achieved through carboxylation reactions where the CO2 molecule is used to produce chemicals such as methane, methanol, syngas, urea and formic acid. CO2 can also be used as a feedstock to produce fuels (e.g. in the Fischer–Tropsch processiv).

With the exception of EOR, which is a well-established process, companies involved tend to be start-ups aiming to profit on the back of hype around negative emissions, in an attempt to increase the value of captured CO2.”

However, using CO2 in this way is energy intensive since it is thermodynamically highly stable: a large energy input is required to make the reactions happen. Furthermore, chemicals and fuels are stored for less than six months before they are used and the CO2 is released back into the atmosphere very quickly.v As with EOR, this is CCU, but not Storage.

Creating biofuels from microalgae: CO2 help cultivate microalgae that are used to produce biofuels. In this case, microalgae would fix CO2 directly from waste streams such as power station flue gases. Microalgae are cultivated in giant open-air ponds that require a large land Concerns have been raised about plans to use genetically modified algae to produce biofuels: containment of the organisms would be next to impossible, and if organisms escape the consequences for human health and natural environments are unknown.vii The US-based Algae Biomass Organization promotes CCUS with microalgae, and many algae biofuel companies have already attempted to combine algae cultivation with industrial power plants that provide CO2. Canada-based Pond Technologies is one such company, which has three pilot facilities aimed at producing algae-derived bioproducts from the steel, cement, oil and gas, and power generation industries. Similarly, the Tata Steel manufacturing facility in Port Talbot, UK, has partnered with the UK EnAlgae program to test the use of flu gases for algae cultivation.viii

Carbon negative plastics

A company called Newlight Technologies has recently commercialized a process that captures methane from farming processes and converts it into plastic, at a factory in California.ix However, this carbon capture technology would only be effective if the plastics never degraded, or were never incinerated as waste.

Can captured CO2 be stored in concrete? Not without expending large amounts of energy on transportation and processing.

Mineral carbonation of CO2 –carbon negative concrete?

Mineral carbonation is a chemical process where CO2 reacts with a metal oxide such as magnesium or calcium to form carbonates. The idea is to use materials in concrete construction that lock in CO2 as a way of “greening” the significant emissions of the cement industry. It is similar to Enhanced Weathering (see factsheet) where silicate minerals found naturally in rocks react with CO2 in the atmosphere and turn into stable carbonates. Companies such as Carbicrete claim to be producing carbon-negative concrete by using steel-slag, a waste product from steel manufacturing, instead of cement. CO2 is then injected into the wet concrete, which reacts with the slag and forms mineral carbonates.x

Another company, Calera, is hoping to scale up its method of concrete production using captured CO2 to create a form of calcium carbonate cement.xi These processes, in theory, could be capable of storing CO2 for long periods. However, as with Enhanced Weathering, the energy penalty and costs including the mining, transportation and preparation of the minerals, are massive and likely outweigh any benefits.xii

Food from captured CO2

Another example of CCU (but not storage! ) is Climeworks’ Direct Air Capture unit in Zurich (see Direct Air Capture factsheet). The facility pumps captured CO2 into nearby greenhouses, increasing the yield in the vegetables grown there by up to 20%.xiii

Of course, as soon as the food is digested or composted, a significant amount of the carbon will be re-released. And plants are already quite good at capturing CO2 from the atmosphere, without requiring large infrastructure developments and greenhouses.

Reality check

All of the aforementioned technologies are being commercialized to varying extents and levels of success. With the exception of EOR, which is a well-established process, companies involved tend to be start-ups aiming to profit on the back of hype around negative emissions, in an attempt to increase the value of captured CO2.

Further reading

ETC Group and Heinrich Böll Foundation, “Geoengineering Map.”

The Big Bad Fix: The Case Against Climate Geoengineering,


i. Rosa Cuéllar-Franca and Adisa Azapagic, “Carbon capture, storage and utilisation technologies: A critical analysis and comparison of their life cycle environmental impacts”, Journal of CO2 Utilization, Vol. 9, 2015

ii. Global CCS Institute, “Large-scale CCS facilities”, 2017,

iii. Rosa Cuéllar-Franca and Adisa Azapagic, 2015

iv. For more information see:

v. Ibid.

vi. Ibid.

vii. Biofuelwatch, “Solazyme: Synthetic Biology Company Claimed to be Capable of Replacing Palm Oil Struggles to Stay Afloat”, 2016

viii. Biofuelwatch, “Microalgae Biofuels Myths and Risks,” 2017

ix. Newlight Technologies, “Technology”,

x. Carbicretem

xi. Calera,

xii. Rosa Cuéllar-Franca and Adisa Azapagic, 2015

xiii. Mark Harris, “The entrepreneurs turning carbon dioxide into fuels”, The Guardian, 2017,

Marine Cloud Brightening (Technology Factsheet)


Marine Cloud Brightening (MCB) refers to manipulating cloud cover to reflect more sunlight back to space. It is a proposed Solar Radiation Management (SRM) technique. MCB could reduce the temperature of the atmosphere and oceans because they would absorb less of the sun’s energy, but it would not reduce levels of greenhouse gases. Proponents of MCB aim to create whiter, more reflective clouds by shooting participles (salt from seawater droplets or bacteria) into clouds and increasing cloud condensation nuclei (the tiny particles around which clouds form). One proposal involves spraying seawater from land or via many thousands of robotic boats into marine clouds.1 However, MCB, like all SRM, will have impacts on weather patterns. Who would decide where to put these possibly drought or flood-causing clouds?

Models also show that once you start cooling the Earth with SRM approaches, you must do even more of it to keep achieving the same effect.

Actors involved

The most prominent advocates of MCB are John Latham from the National Center for Atmospheric Research at the University of Colorado and Stephen Salter from the University of Edinburgh. Salter has promoted protecting sea ice by seeding clouds that move from the Arctic from the Faroe Islands. There is no indication that this experiment is moving forward. Another proponent, Phil Rasch of the Pacific Northwest National Laboratory, has argued that based on “very artificial” models that assume “perfect cloud condensation nuclei,” engineers could offset warming substantially, so long as they seeded the clouds above an astonishing quarter to half of the world’s oceans.2

The first major open-air experiment was to be overseen by the Silver Lining Project in San Francisco. David Keith and Ken Caldeira (prominent geoengineering researchers and proponents) steered some support from the Bill Gates-funded FICER fund3 to develop the nozzle for ships that would fire tiny saltwater particles into the clouds, and in 2010 a large-scale experiment involving 10 ships and 10,000 km2 of ocean was announced. But after media reported on the experiment, all traces of the project and its scientific collaborators disappeared from the Silver Lining Project’s website.4

A few years later, the Silver Lining Project resurfaced as the Marine Cloud Brightening Project.5 With support from the University of Washington, their first land-based field experiment is scheduled in Monterey Bay, California. They will set up nozzles on shore and spray clouds as they roll in, observing if they are whitened, while sensors on land will assess if this has led to a reduction of incoming solar radiation. They have already conducted wind-tunnel testing of a prototype nozzle in California. They then plan to move experimentation to sea, propelling droplets from a small ship.6 Initially scheduled for the summer of 2017, the experiment has been delayed for lack of funding.

The Ocean Technology Group at the University of Sydney is also proposing Marine Cloud Brightening experiments to save the Great Barrier Reef from bleaching.7

Impacts of the technology

While modelling results predict that MCB would reduce average global temperatures, they also show that it could have considerably varied and potentially detrimental impacts in different parts of the world.8 For example, global mean precipitation is modelled to decrease along with temperatures – one study shows that precipitation could decrease up to 2.3%. South America is predicted to become warmer and dryer with MCB.9 Substantial rainfall reduction over the Amazon basin is predicted,10 which would be an ecological disaster. Another study predicts a massive 7.5% increase in runoff over land, primarily due to increased precipitation in the tropics, even though global mean precipitation decreases.11 Although researchers have optimistically suggested that precipitation changes “could be circumvented by not seeding in a particular area,”12 these studies show the extent to which geoengineering is likely to have major unintended consequences, and how poorly understood those consequences still are.

The models also show that once you start cooling the Earth with MCB (and indeed all other SRM approaches), you must do even more of it to keep achieving the same effect. For MCB, this would mean further cloud modification, in terms of increasing both the regions where clouds were modified and the amount by which they were modified. The problems created by a sudden termination of the geoengineering, e.g. a rapid increase in temperatures, would therefore only worsen as time went on.13 A recent study has highlighted how sudden SRM termination would significantly increase the threats to biodiversity from climate change, owing to these rapid and unprecedented temperature changes.14

Marine Cloud Brightening could have negative effects on regional farming, such as strawberry cultivation.

Researchers have also pointed out the vulnerability of MCB to physical attack, given that spray vessels would be in the open oceans. If many or all the cloud-spraying vessels were prevented from operating, there would be a rapid rise in global temperature, with all the accompanying changes in weather patterns and other adverse consequences.15 If we can imagine a dystopian future where geoengineering is widely deployed, then the threat of conflict over its deployment and its impacts does not seem far-fetched.

It has also been suggested that MCB could be deployed alongside other geoengineering techniques (“cocktail geoengineering”), such as Stratospheric Aerosol Injection (SAI) or microbubble ocean whitening (see corresponding fact sheets16) with MCB used to “fine tune” on a more localised level. It could even be used to create localised warming via seeding, to “optimise this fine tuning.”17

Reality check

So far, no outdoor experiments have been conducted with this particular technology, although it is conceivable that this will happen in the near future given sufficient funding.

Further reading

ETC Group and Heinrich Böll Foundation, “Geoengineering Map.”

The Big Bad Fix: The Case Against Climate Geoengineering,


1. University of Washington, “Could spraying particles into marine clouds help cool the planet?” Science Daily, 2017,

2. Philip Rasch et al., “Global Temperature Stabilization via Cloud Albedo Enhancement Geoengineering Options to Respond to Climate Change,” Response to National Academy Call, 2009

3. The Keith Group, “Fund for Innovative Climate and Energy Research,” Harvard University,

4. ETC Group, “Geoengineering Experiments Contested at UN meeting in Nairobi,” 2010,

5. Lisa Krieger, “Cloud brightening experiment tests tool to slow climate change,” The Mercury News, 2015,

6. Hannah Hickey, “Could spraying particles into marine clouds help cool the planet?” Washington University, 2017,

7. Fiona Ellis-Jones, “Great Barrier Reef: Making clouds brighter could help to curb coral bleaching, scientists say,” ABC News, 2017,

and Alister Doyle, “Scientists dim sunlight, suck up carbon dioxide to cool planet,” Reuters, 2017,

8. Andy Jones et al., “Climate impacts of geoengineering marine stratocumulus clouds,” J. Geophys. Res. Vol. 114, 2009

9. Andy Jones et al., “A comparison of the climate impacts of geoengineering by stratospheric SO2 injection and by brightening of marine stratocumulus cloud,” Atmos. Sci. Let., Vol. 12, 2010, pp. 176–183

10. Andy Jones et al., 2009

11. Govindasamy Bala and Nag Bappaditya, “Albedo enhancement of marine clouds to counteract global warming: impacts on the hydrological cycle,” Climate Dynamics, 2010

12. John Latham et al., “Marine cloud brightening,” Phil. Trans. Royal Soc. A, Vol. 370, 2012, pp. 4217–4262

13. Andy Jones et al., 2010

14. Christopher Trisos et al., “Potentially dangerous consequences for biodiversity of solar geoengineering implementation and termination,” Nature Ecology & Evolution, Vol. 2, 2018, pp. 475–482

15. John Latham et al., 2012

16. See Geoengineering Monitor, “Stratospheric Aerosol Injection” and “Microbubbles” Technology Fact Sheets, April 2018.

17. Ibid.

Bio-Energy with Carbon Capture and Storage (BECCS)


BECCS describes capturing CO2 from bioenergy applications and sequestering it through either Carbon Capture and Storage or Carbon Capture, Use and Storage. BECCS is considered “carbon negative” because bioenergy is wrongly considered “carbon neutral” based on the idea that plants will regrow to fix the carbon that has been emitted.

BECCS has taken centre stage as a climate “mitigation” technique and as a “negative emissions” technology.1  Virtually all of the likely 2°C scenarios considered by the IPCC in their most recent assessment report assume that BECCS will be technically and economically viable and successfully scaled up, which has not been proven.2 Across the scenarios considered by the IPCC, an average of 12 gigatons of removal annually through BECCS after 2050 is required, equivalent to a quarter of current global emissions.3 However, it seems highly likely that BECCS may never be technically and economically viable.4

Actors involved

As of 2018, there is only one BECCS project in the world: ADM’s Decatur corn ethanol refinery in the USA.5 CO2 is captured from the fermentation process and injected underground. This has been essentially a “proof of concept” project, funded by the Department of Energy (US$ 141 million6), which claims that it provides a “carbon negative footprint.” In reality, the refinery is powered by fossil fuels and corn is an energy-intensive crop, giving it a net carbon positive footprint.7

There are at least four more ethanol plants in North America where captured CO2 is used for Enhanced Oil Recovery (see CCS fact sheet8). There are also plans for very small facilities in Brazil, Saudi Arabia, the Netherlands and Norway.9 For all the emphasis on BECCS from industry and policy-makers, it is clear that the technology is not keeping up with expectations.

Biodiversity-destroying eucalyptus plantations would provide much of the raw material for BECCS. (Allysse Riordan/Flickr)


A large body of peer-reviewed literature indicates that many bioenergy processes result in even more CO2 emissions than burning the fossil fuels they are meant to replace – it is certainly not carbon neutral.10 This is due to emissions from (but not limited to): converting land into energy crop production which sometimes results in the displacement of food production, biodiverse ecosystems such as forests, or other land uses (indirect land use change); the degradation and overharvesting of forests; and emissions from soil disturbance, harvesting and transport.

Because BECCS needs fast-growing energy crops, its deployment could also require more than doubling fertilizer inputs, requiring as much as 75% of global annual nitrogen production. This would seriously exacerbate environmental degradation and emissions associated with fertilizers and agrochemicals, which currently cause large-scale anoxia in oceans and eutrophication of streams and rivers, for example.11

The BECCS theory: capture carbon with trees; burn trees for energy; capture carbon at the smokestack; bury carbon underground.

Capturing CO2 from bioenergy processes would be even more technically challenging and energy intensive than capturing CO2 from coal plants, which has been attempted at great cost and with little success. A unit of electricity generated in a dedicated biomass power plant results in up to 50% more CO2 emitted than if generated from coal,12 meaning that yet more energy must be dedicated to the carbon capture process itself. Further still, there serious doubts that geological storage of CO2, in old oil and gas reservoirs, or deep saline aquifers, will be effective and reliable (see CCS fact sheet13).

A study looking at what would be required to sequester 1 gigaton of carbon annually using BECCS, equivalent to around a fiftieth of global annual emissions, concluded that between 218 and 990 million hectares of land would be needed to grow the biomass (this is 14-65 times as much land as the US uses to grow corn for ethanol).14 More recent studies calculate that the biomass required for BECCS would take up between 25 and 80% of current global cropland.15

Land conversion on such a scale would result in severe competition with food production, depletion of freshwater resources, vastly increased demand for fertilizer and agrochemicals, and loss of biodiversity, among other problems.16 Indeed, one study concluded that large-scale deployment of BECCS could result in a greater loss of terrestrial species than temperature increases of 2.8°C.17

Scaling up bioenergy to the extent envisaged would have devastating impacts on livelihoods and compete directly with food production. Severe human rights abuses and land-rights conflicts are already being caused by bioenergy globally, for example for biofuel production and tree plantations for wood pellet production. Indeed, industrial monoculture tree plantations would likely provide much of the raw material for BECCS.18 At such a scale, current harm to communities and impacts from land-grabbing would be dwarfed by BECCS.

One recent assessment projected that large-scale BECCS deployment could result in sweeping food price rises across Africa, Latin America, and Asia, threatening food security for many of the world’s most vulnerable. Another recent study indicated that even modest increases in bioenergy development could increase the number of malnourished children in sub-Saharan Africa by 3 million.19

Reality check

BECCS is currently purely aspirational and, given the technical challenges, it is unlikely to ever be scaled up significantly. However, fantasy technologies like BECCS allow polluters to keep using fossil fuels through the false hope that “negative emissions” can remove carbon from the atmosphere in the future, delaying urgent action on climate change further. This is likely to be the most dangerous impact of BECCS.

Further reading

Biofuelwatch and Heinrich Böll Foundation, “Summary BECCS report: Last ditch climate option or wishful thinking?”

Global Forest Coalition, “The risks of large-scale biosequestration in the context of Carbon Dioxide Removal,”

ETC Group and Heinrich Böll Foundation, “Geoengineering Map.”

The Big Bad Fix: The Case Against Climate Geoengineering,


1. The Royal Society, “Geoengineering the climate: science, governance and uncertainty,” 2009

2. Kevin Anderson and Glen Peters, “The trouble with negative emissions,” Science, Vol. 354, Issue 630, 2016 pp. 182-183

3. Christopher Field and Katherine Mach, “Rightsizing carbon dioxide removal,” Science, Vol. 356, 2017, pp706–707

4. Almuth Ernsting and Oliver Munnion, “Last-ditch climate option or wishful thinking? Bioenergy with Carbon Capture and Storage,” Biofuelwatch, 2015

5. Office of Fossil Energy, “Archer Daniels Midland Company,”

6. ETC Group and Heinrich Böll Foundation, “Illinois Industrial CCS (former Decatur project,” Geoengineering Map, 2017,

7. Chris Mooney, “The quest to capture and store carbon – and slow climate change — just reached a new milestone,” Washington Post, 2017,

8. See Geoengineering Monitor, “Carbon Capture and Storage,” Technology Fact Sheet, April 2018.

9. ETC Group and Heinrich Böll Foundation, “Carbon Dioxide Removal,” Geoengineering Map, 2017,

10. A compilation of peer-reviewed literature is available here:

11. Wil Burns and Simon Nicholson, “Bioenergy and carbon capture and storage (BECCS): the prospects and challenges of an emerging climate policy response,” Journal of Environmental Studies, 2017

12. Partnership for Policy Integrity, “Carbon emissions from burning biomass for energy,” 2015,

13. See Geoengineering Monitor, “Carbon Capture and Storage,” Technology Fact Sheet, March 2018.

14. Lydia Smith and Margaret Torn, “Ecological limits to terrestrial biological carbon removal,” Climate Change, Vol. 118, Issue 1, 2013, pp. 89-103

15. Christopher Field and Katherine Mach, 2017

16. Wil Burns and Simon Nicholson, 2017

17 Phil Williamson, “Emissions reduction: scrutinize CO2 removal methods,” Nature, Vol. 530, 2016, pp. 153–155

18. Global Forest Coalition, “The impacts of large-scale biosequestration in the context of Carbon Dioxide Removal,” 2017,

19. Wil Burns and Simon Nicholson, 2017

Enhanced Weathering (Technology Factsheet)


Enhanced weathering on land (terrestrial)
Mined olivine (magnesium iron silicate) is ground to a powder and either dumped on beaches where wave action disperses it into water or is spread on land. The idea is to control levels of atmospheric CO2 through natural chemical weathering processes1 that draw CO2 out of the atmosphere (referred to as carbonation) and sequester it in newly-formed rock mineral, magnesium carbonate. Carbon uptake levels are still relatively unknown, as are the effects of large-scale dumping on marine, terrestrial and freshwater environments. The chemical effects of adding this mineral to other ecosystems are also unknown. Massive mining operations to extract olivine, possibly thousands of times larger than the current scale of production, would exacerbate the already disastrous effects of mining on the world’s ecosystems and local populations.

When energy inputs such as mining, processing and transportation are included, the overall energy requirement for enhanced weathering is huge

Enhanced weathering in the oceans (marine)

This technique, similar to treating acidic agricultural lands with lime, proposes adding chemical carbonates to the ocean to theoretically increase alkalinity and therefore carbon uptake. The rate at which these minerals would dissolve, as well as the expense involved in amassing and dispersing enough of them to make an impact, is a major practical concern, as is the effect on the complex ocean ecosystem.2 The increased demand for minerals would also translate into increased mining activities, with the above-mentioned impacts.3

Actors involved

The Leverhulme Centre for Climate Change mitigation in the UK is conducting enhanced weathering field trials in the USA, Australia and Malaysia. They have identified expansive crop areas where they may add crushed basalt. In Malaysia, quarried and crushed basalt is added to oil palm plantations and is studied for its impacts on crop yield and carbon sequestration.4

Other developments in the field of enhanced weathering are limited to research projects, such as the Oxford Geoengineering Programme5 and University of Utrecht/The Olivine Foundation, in the Netherlands.6

Weathering is a theoretical process of sequestering carbon by scattering mined minerals over vast areas.


A study on enhanced weathering lists the following possible problematic side effects: Change in pH of soils and surface waters (streams, rivers, lakes), affecting terrestrial and aquatic ecosystems; change in silicon concentration of surface waters, affecting ecosystems via altered nutrient ratios; release of trace metals associated with target minerals (particularly Nickel and Chromium in the case of olivine application); generation of dust; socioeconomic and socio-political consequences for agricultural communities of a new, large-scale industrial and financial enterprise; and the environmental costs of up to three orders of magnitude increase in olivine mining globally.7

While olivine fertilization of the ocean “mimics” a natural process, it is not natural at all. Olivine would be delivered to ecosystems at rates far higher than normal, which could lead to negative consequences for ecosystems where it is introduced, such as phytoplankton blooms and anoxic dead zones, and other unknown effects on deep-sea life and thus on biogeochemical processes. At such a large scale, enhanced weathering could change the ecology of the oceans.8 Such changes could lead to an increase in the microbial organisms that produce other greenhouse gases such as methane and nitrous oxide, which have much higher warming impacts than CO2.9

The amount of olivine necessary for these applications is extremely large – comparable to present day global coal mining,10 which would bring serious and vast mining impacts. When energy inputs such as mining, processing and transportation are included, the overall energy requirement for enhanced weathering is huge.11

The oil and gas company Shell funded a small company called Cquestrate (run by Tim Kruger, who now manages The Oxford Geoengineering Project12) in the UK to conduct feasibility studies in to adding limestone to the oceans. Although this project never got off the ground, it is a good example of the potential impacts of this kind of geoengineering approach. The project developer suggested that to offset current global carbon emissions, 10.5km3 of limestone could be mined each year from the “sparsely populated” Nullarbor Plain in Australia and dumped into the ocean.13 Significantly less than 10.5km3 of hard coal is mined globally each year. Large scale mining operations would be required to implement this kind of scheme, and the process would harm ecosystems and communities. Further, the Nullarbor Plain is home to the aboriginal Wangai people, who were forcibly removed from their ancestral lands once before for nuclear testing in the 1950s and have since received compensation for the injustice and have reoccupied the plain. The Nullarbor Plain was also given formal Wilderness Protection Status in 2011 to protect its unique environment, which contains 390 species of plants and many habitats for rare species of animals and birds.14

Reality check

While field-scale trails adding crushed basalt to cropland are being conducted, other research into enhanced weathering is purely theoretical, and based on modelling exercises.

Further reading

ETC Group and Heinrich Böll Foundation, “Geoengineering Map.”

The Big Bad Fix: The Case Against Climate Geoengineering,


1. See Olaf Schuiling and Oliver Tickell, “Olivine against climate change and ocean acidification,” Innovation Concepts, 2011,

2. Miriam González and Tatiana Ilyina, “Impacts of artificial ocean alkalinization on the carbon cycle and climate in Earth system simulations,” Geophysical Research Letters, Vol. 43, 2016

3. David Keller et al., “Potential climate engineering effectiveness and side effects during a high carbon dioxide-emission scenario,” Nature Communications, Vol. 5, 2014

4. Leverhulme Centre for Climate Change Mitigation, “Theme 3 – Applied weathering science,”

5. Oxford Geoengineering Programme, “Enhanced Weathering,”

6. The Olivine Foundation, ”Let the Earth save the Earth,”

7. Jens Hartmann et al., “Enhanced chemical weathering as a geoengineering strategy to reduce atmospheric carbon dioxide, supply nutrients and mitigate ocean acidification,” Reviews of Geophysics, Vol. 51, 2013, pp. 113–149
Sallie Chisholm et al., “Dis-Crediting Ocean Fertilization,” Science, Vol. 294, 2001, pp. 309-310

8. Sallie Chisholm et al., “Dis-Crediting Ocean Fertilization,” Science, Vol. 294, 2001, pp. 309-310

9. Jesse Abrams, “An Investigation of the Geoengineering Possibilities and Impact of Enhanced Olivine
Weathering,” University of Bremen, 2001,

10. Peter Köhler et al., “The geoengineering potential of artificially enhanced silicate weathering of olivine,” Proceedings of the National Academy of Sciences of the United States of America, Vol. 107, 2010, pp. 20228-20233

11. Pete Smith et al., “Biophysical and economic limits to negative CO2 emissions,” Nature Climate Change, Vol. 6, 2015, pp. 42-50

12. Kruger was one of the authors promoting a set of principles for governance that have been influential among the geoengineering proponents, including the astonishing notion that geoengineering is a public good. See and

13. Cquestrate, “Detailed description of the idea,”

14. Wikipedia, “Nullarbor Plain,”

Marine Cloud Brightening Project: Geoengineering Experiment Briefing

» Download this briefing [pdf]

Location: Moss Landing, California, USA (Between Monterey and Santa Cruz)

Budget: $16.3 million


The Marine Cloud Brightening Project (MCBP) aims to test the premise that spraying a fine mist of sea water into clouds can make them whiter, reflecting more sunlight back into space. The MCBP, a form of Solar Radiation Management (SRM) began with indoor development and testing of spray nozzles, and is moving toward a land-based field test in 2018, followed by ship-based tests and a larger-scale sea test later on.

Armand Neukermans discusses his plans with a Bay Area TV station.

After previous attempts to test “cloud brightening” as a geoengineering technique (e.g. the Silver Lining project) were cancelled after a public outcry, the project’s leaders have taken a smaller-scale, more public relations savvy approach.


Initial support for development of hardware came from the Bill Gates-backed Fund for Innovative Climate and Energy Research (FICER). It is unclear where the funding for the project’s planned field tests is coming from.

Key dates:

Field tests were initially slated for as early as 2016, but have been delayed for lack of funding. The first land-based experimental use of cloud brightening hardware is now expected to take place in August 2018. The project hopes to move to ship-based tests within 2 years and then a large cloud brightening experiment 2-3 years after that.

Key players in MCBP:

Thomas Ackerman
Professor in Atmospheric Sciences, University of Washington

Robert Wood
Professor of Atmospheric Sciences, University of Washington

Philip J. Rasch
Pacific Northwest National Laboratory (PNNL)

Armand Neukermans
Former engineer at Xerox Labs, HP

Kelly Wanser
CEO of Luminus Networks

Stephen Salter
Emeritus Professor of Engineering Design, University of Edinburgh

John Latham
Professor emeritus at the University of Manchester (UK)

Regulatory status:

The UN Convention on Biodiversity has passed a moratorium on geoengineering deployment and experimentation (2010) that covers SRM, including experiments like this one. However, the US is not a party to the CBD. The US is a party to the London Convention and Protocol (on marine pollution) that has declared itself competent to rule on “marine geoengineering.” While spraying from land is not “marine.” future ship-based steps do clearly fall under the London Convention.

“We could… consider the climate system as a piano in which the spray regions are the keys, some black some white, on which a wide number of pleasant (or less unpleasant) tunes could be played if a pianist knew when and how hard to strike each key.” –Stephen Salter

The US is also a party to the UN Environmental Modification Convention (ENMOD) prohibits hostile use of environmental modification technology globally. Marine tests are also governed by the provisions of the UN Convention on the Law of the Sea (UNCLOS) and as tests move offshore, the current negotiations over activities affecting Biodiversity Beyond National Jurisdiction (BBNJ) become highly relevant.

Cloud brightening is on of an array of geoengineering techniques that aim to reflect sunlight back into space on a mass scale.

Under US Federal law (National Weather Modification Policy Act of 1976), any modification of the weather is required to be reported to the National Oceanic and Atmospheric Administration, and the results of research must be made public.

The proposed tests are taking place on Popeloutchom, the traditional territory of the Amah Mutsun Tribe, an Indigenous group dedicated to protecting its terestrial and aquatic ecosystems. Future large-scale marine cloud brightening trials could potentially affect the weather and airspace of several Indigenous communities in California’s central coast region.

For Indigenous Nations, territorial sovereignty spans land, underground and airspace as a whole. When it comes to legal precedent, one California-based lawyer has made a persuasive case that tribal governments’ sovereignty extends to the airspace over their lands under US law as well.

Possible impacts:

The effects of large-scale testing of MCB geoengineering techniques are unknown, but could affect rainfall in the immediate area, as well as creating unpredictable changes to regional weather patterns at a distance. For example, marine cloud brightening in the Pacific and elsewhere may lead to reduced rainfall in the Amazon basin.

Blocking sunlight on a scale on a scale big enough to modify global temperatures would have massive effects on weather patterns, which could lead to weaponization of geoengineering. Computer models suggest that Solar Radiation Management methods like cloud brightening could lead to drought in the Sahel region of Africa or South America. In the likely scenario that SRM creates winners and losers in terms of rainfall or other weather factors, the techniques would inevitably become a tool of geopolitics.

The area surrounding Moss Landing is also a major strawberry growing region, a form of agriculture that depends heavily on rainfall, and has been experiencing prolonged drought. If precipitation is altered by cloud brightening, this could negatively affect agriculture in the region. The proponents have said that the first experiments will not directly whiten clouds (only test out the hardware) but later experiments will do so.

So far, cloud brightening has struggled to find funding due to the controversial nature of its proposals, but a successful small-scale test could help to legitimize geoengineering research and open the door to larger-scale implementations and much more funding. If the tests proceed, and lead to full implementation, the implications could become planetary in scale. These experiments are the first step on a path to unilateral implementation of geoengineering, exploitation of “alternatives” to reducing greenhouse gas emissions by fossil fuel companies, and military uses of the technology.

The California coast (and the entire Pacific coastline down to Peru) are regarded as some of the most promising locations for SRM projects. If larger tests and deployment proceed, the North and South American Pacific coastal regions are the most likely locations.
The vision of the key players remains the creation of a planetary scale technology that can change the global temperature and be flexibly operated to cool and alter different regions. As MCB proponent and researcher Stephen Salter put it in a research paper, “We could… consider the climate system as a piano in which the spray regions are the keys, some black some white, on which a wide number of pleasant (or less unpleasant) tunes could be played if a pianist knew when and how hard to strike each key.”

Project details:

The first major open-air experiment was to be overseen by a US Silicon Valley entrepreneur Kelly Wanser, who established a company, Silver Lining Inc, later renamed The Silver Lining Project, in San Francisco. Leading Geoengineering researchers David Keith and Ken Caldeira steered some funding from the Bill Gates-backed FICER fund to project leader Armand Neukerman – the inventor of the earliest inkjet printers who worked at Xerox Labs and Hewlett Packard. Neukerman’s goal has been to develop the nozzle for ships that would fire saltwater as tiny particles into the clouds, at a rate of trillions per second. The nozzle must emit particles that are small enough – 0.2 to 0.3 micrometers – to rise and remain suspended in air. In 2010, Wanser announced a large-scale experiment involving 10 ships and 10,000 square kilometres of ocean that would take place in three or four years. But after media reported on the experiment, including the involvement of Gates in funding Neukerman’s work, all traces of the project and its scientific collaborators disappeared from the Projec’s website.

A few years later, the same proposals resurfaced as the Marine Cloud Brightening Project, still with Kelly Wanser as the executive director. In media coverage, they have focused on presenting themselves not as a commercial outfit but as a folksy collection of harmless, retired engineers tinkering in their labs instead of hitting the golf range – referring to themselves as the “Silver Linings.” Thomas Ackerman, a scientist at Washington University and one of the formulators of the Nuclear Winter theory, joined the project as a principal investigator in 2014.

Under the aegis of the University of Washington, their first land-based field experiment is slated to take place at Moss Landing, Monterey Bay, California. Tom Ackerman told a geoengineering conference in 2014 that they would set up nozzles on the shoreline and spray clouds as they roll in, observing if they were whitened, while sensors on the land would assess if this led to less incoming solar radiation.

More recent press reports include the test organisers stressing that the first experiments will not whiten any actual clouds, just test the hardware. They have already conducted wind-tunnel testing of a prototype nozzle in 2015 in the California’s Bay Area. Reports have also emerged that Kelly Wanser has been scouting to hire for a public relations whiz for the Monterey experiment – perhaps with the hope of not replicating the Silver Linings Project media fiasco. They would then move experimentation to sea, for a 2-3 year phase propelling droplets from a small ship. After that, the project would move to a larger at-sea cloud whitening test initially slated for the summer of 2017, but has since been delayed. The land-based experiment has been delayed for lack of funding but is expected to move ahead in August 2018.


Briefing prepared by ETC Group.

The Ice 911 Project: Geoengineering Experiment Briefing

» Download this briefing [pdf]

Locations: Near Barrow, Alaska; the Beaufort Gyre (an ocean current flowing past Nunavut and Alaska); and Fram Straight (between Greenland and Svalbard)

Budget: $97,630 (based on 2015 crowdfunder1, which raised $3,103 from 24 donors, but full implementation would cost millions)


The Ice 911 project2 proposes to scatter millions of tiny glass bubbles over arctic ice, which would reflect sunlight, slowing the melting process in the summer months. The project’s proponents are pitching the project as a form of “soft geoengineering”, which they claim is less damaging and more reversible than other techniques. Their initial plan is to use their glass bubbles to prevent strategic areas of ice from melting, which could block larger ice sheets in the Arctic Ocean from floating south (where they would melt faster).

Experiments are deploying millions of tiny glass spcheres to reflect sunlight and delay melting of ice.

The effects of a large-scale geoengineering experiment like Ice 911 are difficult to determine. Just like other solar radiation management experiments, Ice 911 would develop infrastructure and technology that aim to change global weather patterns. Reflecting sunlight back into space on a massive scale in the Arctic could have unanticipated changes on precipitation, temperature and humidity all over the globe.
In addition to potentially catastrophic unanticipated effects, anticipated effects could be the most dangerous: the ability to change weather on other parts of the planet could become a powerful weapon wielded by governments or private actors.

Key Players:

Project leader Leslie Field-Barth is an electrical engineer and researcher who has worked for Chevron and various Silicon Valley firms, and currently runs a nanotechnology consultancy. She also teaches at Stanford.

Key dates:

According to the project, Ice 911 has already conducted experiments that covered 17,500 square metres of ice with their glass spheres in 2017 in Alaska.

In 2018, the Ice 911 project intends to cover .25 km of ice with its materials. In 2019, their stated plan is to scale that up by 20x on ice sheets in the Beaufort Gyre or Fram Strait.

Potential Impacts:

Ice 911’s goal is to spread millions of hollow glass beads the size of grains of sand over ice in order to reflect sunlight and slow the melting of ice, blocking the southward flow of larger bodies of ice and preventing those from melting as well. This could affect weather patterns locally and globally, habitat and animal migration in the Arctic, as well as other unanticipated effects,

While increasing the albedo of ice might seem more innocuous than, for example, spraying thousands of tonnes of sulphites into the stratosphere, it could have similar effects on weather patterns if implemented on a large enough scale to have an impact on the climate. Computer models show that “albedo enhancement” and “solar radiation management” (SRM) projects – especially coupled with a continued increase in atmospheric CO2 – could have profound effects on rainfall patterns in vulnerable regions like the Sahel and the Amazon basin, leading to droughts that could affect millions of people and threaten biodiversity.

To the extent that Ice 911 is succesful at changing global temperatures, it can become a tool of geopolitical power, with powerful nations claiming that they’re modifying global weather patterns for the good of the planet while they may be putting at risk the sources of food and water for many million peoples in Asia and Africa.

As such, the same concerns about weaponization that have been raised about other SRM projects apply. Once Ice 911 has been implemented on a large scale, data can be collected about effects on global weather patterns.

Reflecting sunlight back into space on a scale big enough to modify global temperatures would have massive effects on weather patterns, which could lead to weaponization of geoengineering. Computer models suggest that Solar Radiation Management methods like cloud brightening could lead to drought in the Sahel region of Africa or South America. In the likely scenario that SRM creates winners and losers in terms of rainfall or other weather factors, the techniques would inevitably become a tool of geopolitics.

To the extent that Ice 911 is succesful at changing global temperatures, it can become a tool of geopolitical power, with powerful nations claiming that they’re modifying global weather patterns for the good of the planet while they may be putting at risk the sources of food and water for many million peoples in Asia and Africa.

In the Arctic, rapid changes to the pattern of ice floes could impact animal migration as well as local weather patterns. Climate change is already having profound effects in the Arctic, but that doesn’t mean major changes to the circulation of ice and ocean currents would be an improvement. Without significant study, major unanticipated negative impacts could result, affecting conditions for hunting, fishing and trapping in nearby communities, animal habitat, plant growth, and changes to quality of life in settled areas. Indeed, it’s possible that major unanticipated effects could negate the “positive” effects anticipated by the authors of Ice 911.

Another source of unanticipated effects could be the glass bubbles themselves. Ice 911 compares its tiny spheres to sand and claims they are harmless to ingest, but there are key differences: hollow sphere may float, creating unanticipated changes in ocean temperature or photosynthesis of ocean life downcurrent; the highly reflective nature could affect animal behaviors, cause disorientation or be mistaken for food sources; and the spheres may have different effects on soil conditions, plant life or organisms that eat them, or further up in the food chain.

Regulatory Status:

The UN Convention on Biodiversity has passed a moratorium on ocean fertilization (2008) and on geoengineering (2010) that cover experiments like this. However, the US is not a party to the CBD. The UN Environmental Modification Convention (ENMOD) prohibits military use of weather modification technology globally.

The London Convention (the International Maritime Organization body that oversees dumping of wastes at sea) has also banned all ocean-based geongineering.

Under US Federal law (National Weather Modification Policy Act of 1976), any modification of the weather is required to be reported to the National Oceanic and Atmospheric Administration, and the results of research must be made public.

A polar bear on an ice floe in the Fram Straight. Covering ice with millions of tiny glass spheres could have many unanticipated effects on the local food chain, from sea life to whales, bears and Indigenous Inuit communities who depend on hunting. Photo: Creative Commons/Fruchtzwerg’s World

The area around Ukpeaġvik (also known as Barrow) where Ice 911’s 2017 experiment was staged, is owned by the Ukpeaġvik Iñupiat Corporation, whose shareholders are people of Iñupiat descent.
The Beaufort Gyre covers the northernmost part of the Arctic Ocean on the Canadian side, and comes into contact with the area of the Nunavut Land Claim. The Land Claim, signed in 1993, grants regional Inuit organization rights to water, and compensation if the “quality, quantity or flow” of water they depend on is affected by a “project or activity”.

The Fram Straight is located between autonomous Danish territory of Greenland and the Norwegian territory of Svalbard. Both countries are signatories to the UN Convention on Biodiversity.

Action required:

The Ice911 project has been developed under the radar of current applicable regulations, and no critical assessment of its impacts has been made. While the existence and immediate impacts of the project are concern enough, the cumulative and future impacts of a scaled up version require the immediate attention of regulatory bodies and civil society organizations.




Briefing prepared by ETC Group.

The Big Bad Fix

ETC Group, BiofuelWatch and Heinrich Boell Foundation present a comprehensive argument against geoengineering in this report.

Click here to download the full report (pdf)

As a rapidly warming world manifests heat waves, floods, droughts and hurricanes, geoengineering – large-scale manipulation of the Earth’s natural systems – is being presented as a strategy to counteract, dilute or delay climate change without disrupting energy- and resource-intensive economies. Alarmingly, current debates about this big techno-fix are limited to a small group of self-proclaimed experts reproducing undemocratic worldviews and technocratic, reductionist perspectives. Developing countries, indigenous peoples, and local communities are excluded and left voiceless.

As this report details, each of the proposed geoengineering technologies threatens people and ecosystems. Holistic assessments of the technologies also show that if deployed they are highly likely to worsen rather than mitigate the impacts of global warming.

The irreversibility, risk of weaponization, and implications for global power dynamics inherent in large-scale climate geoengineering also make it an unacceptable option.

Current Geogengineering Attempts Briefing: SCoPEx

Download PDF version: ETC-briefing-SCoPEx


World View Spaceport

Tucson, Arizona, USA

Key Players:

Frank Keutsch, David Keith, John Dykema, and Lizzie Burns, all Harvard Professors. Burns and Keith head the Harvard Solar Geoengineering Research Program.


$20 million ($7m raised as of Oct. ‘17)


The Stratospheric Controlled Perturbation Experiment (SCoPEx) is a planned experiment in a form of geoengineering known as Solar Radiation Management (SRM). SRM techniques aim to block or reflect sunlight before it reaches the earth’s atmosphere, which would hypothetically slow down  global temperature rise. SCoPEx aims to develop a form of SRM known as Stratospheric Aerosol Injection.

The SCoPEx project would spray water, finely-ground chalk and sulfur particles into the upper atmosphere from a high-altitude balloon and measure  how effectively the resulting clouds block sunlight, while also tracking any effects on the air in the upper atmosphere. While the environmental impacts are currently unknown, the political effects of the project, however, are the  most consequential: if the experiments are allowed to proceed, they would legitimize geoengineering and move us one step closer to a global sun-block and more geoengineering in the region.


Funding comes from Harvard University and its Solar Geoengineering Research Program, which is funded by Bill Gates, several venture capitalists and hedge fund higher-ups, a former senior VP at Google, the Hewlett and Alfred P. Sloan foundations (among other philanthropic organizations), and a foreign policy research centre with military ties.

Key dates:

Project initiated: 2015

Research activities: 2017-2024

First field tests programmed: 2018

Regulatory status:

The UN Convention on Biodiversity has passed a moratorium on ocean fertilization (2008) and on  geoengineering (2010) that cover SRM and experiments like this. However, the US is not a party to the CBD. The UN Environmental Modification Convention (ENMOD) prohibits military use of weather modification technology globally.

Under US Federal law (National Weather Modification Policy Act of 1976), any modification of the weather is required to be reported to the National Oceanic and Atmospheric Administration, and the results of research must be made public.

The O’odham Nation, represented by a  handful of tribal governments, have lived in the area around the World View Spaceport for thousands of years. The reservations where the tribal governments exercise extra-constitutional sovereignty under US law cover a vast area of southern Arizona, with traditional territories extending into Mexico. For example, the Pascua Yaqui Tribe’s offices are a 20 minute drive from the Spaceport that will be the SCoPEx staging area.

While the sovereign rights of tribal governments over airspace is an emerging legal area, the Air Force and others have signed Memoranda of Understanding with the tribal governments about their use of O’odham airspace, indicating that government agencies are aware that they have some rights. One lawyer has made a persuasive case that tribal governments have sovereignty over what happens in the airspace over their lands.

Possible impacts:

The environmental effects of SCoPEx are mostly unknown. The project’s web site claims that the amounts released by the project will be “very small compared to other routine releases of material into the stratosphere by aircraft, rockets, or routine balloon flights.”

However, the political effects of the project are easier to predict. As governments continue to fall short of climate targets, David Keith and other geoengineers will be able to point to research findings to bolster the case for larger geoengineering experiments. However, these are not dispassionate scientists, but entrepreneurs backed by venture capitalists who stand to become fabulously wealthy if governments should opt to move forward with an SRM project in the future.

If SCoPEx moves forward, it will contribute to entrenching technology, capital and public relations power of geoengineering and divert resources away from real climate solutions.

Project details:

David Keith, among others, has proposed a suite of field experiments, some to test the effectiveness and risks of geoengineering and others to develop technologies for larger-scale deployment. The closest to execution is SCoPEx. This experiment would try to understand the microphysics of introducing particles into the stratosphere to better estimate the efficacy of different materials to reflect sunlight as part of an effort to develop SRM techniques. They first plan to spray water molecules into the stratosphere from a balloon 20km above the earth, to create a massive icy plume to be studied from the flight balloon. They then aim to replicate it with limestone or calcium carbonate, followed by sulphates.

David Keith’s Earlier Attempts

In 2012, news broke that David Keith and Harvard engineer James Anderson were planning the first outdoor experiment in solar geoengineering. This would have involved the release of particles into the atmosphere from a balloon flying 80,000 feet over Fort Sumner, New Mexico. Their stated aim was to measure how releasing sulfate would impact ozone chemistry, and to test ways to make the aerosols the appropriate size.

The announcement came soon after a controversial proposed field test of another SRM scheme – the British government-funded Stratospheric Particle Injection for Climate Engineering (SPICE) – was cancelled after a global outcry. Keith bemoaned its fate: “I wish they’d had a better process, because those opposed to any such experiments will see it as a victory and try to stop other experiments as well.”

After media revealed Keith’s own experiment, it too was cancelled, and Keith shifted energies to a new incarnation of the project. In early 2017, he helped launch Harvard’s Solar Geoengineering Research Program, backed by several million in funding by billionaires and private foundations.

Now, Keith is covering his bases politically: he claims the amounts of particles released will be small, and  in an attempt to win support among civil society, the project says it will have an independent advisory process for the experiments. This is in keeping with what constitutes a problem with all small-scale experiments like this: the slow and careful accumulation of mainstream legitimacy for large-scale experiments in solar geoengineering in the media, scientific bodies, and institutions of governance, both regionally and globally—ultimately leading toward full deployment.

SCoPEx Funders include:

William and Flora Hewlett Foundation; The Open Philanthropy Project; Pritzker Innovation Fund; The Alfred P. Sloan Foundation; VoLo Foundation; The Weatherhead Center for International Affairs; G. Leonard Baker, Jr.; Alan Eustace; Ross Garon; Bill Gates;  John Rapaport; Michael Smith; Bill Trenchard.

–November 2017 ,

Hydroxyl and methane? SRM proponents fail to consider key aspect of atmospheric chemistry

By Dr. Rachel Smolker

Hydroxyl (OH) is a simple, very short lived but “radical” marriage of one hydrogen and one oxygen molecule. Being “radical” means that it reacts very readily with other chemicals, being an important agent of change. Hydroxyl radicals are referred to as an atmospheric “detergent” because they play a key role in oxidizing, and thereby decomposing various air pollutants, including carbon monoxide, sulphur dioxide, and methane. OH chemistry is closely associated with ozone dynamics – since most OH is formed from UV mediated breakdown of ozone.

A study just published in July 2017 looked at the impact of stratospheric aerosol injection of sulfate particles (SAI), a proposed “solar radiation management” (SRM) approach to geoengineering, on methane. OH converts methane into water and CO2, over time. The longevity, and in turn the concentration of methane in the atmosphere therefore depends in large part on the concentration of OH.[1]

What they found (using models) is that sulfate aerosol injection would have several effects – on planetary albedo, on UV scattering and on circulation of air and sulfate particles between layers of the atmosphere. The two models used by the researchers suggest that those impacts, taken together these would result in an increased longevity of methane by as much as 16% – which would mean 16%more methane in the atmosphere at any one time. This would greatly exacerbate (“force”) warming.[2]

The idea of using SAI has been bandied about for over a decade. David Keith, one of the most avid proponents recently opened a laboratory at Harvard University, with grants from the Gates Foundation and others. This is one of several new academic institutes that have taken up research on geoengineering with grant moneys flowing. The Royal Society and National Academies, among others have written assessments, and reports and debates are increasingly, and disturbingly, more commonplace. Keith and colleagues have announced plans for an open-air experiment in the southwestern USA in 2018.

So how is it, that all of these academics, and all the king’s men have not taken into consideration the impacts of SAI on OH breakdown of methane, until now? My long-time colleague and codirector of Biofuelwatch, Almuth Ernsting, has no Ph.D. in, or formal training in atmospheric chemistry. But she has long been wondering about that possibility. She first learned the importance of hydroxyl in the atmosphere from reading a 2006 book by Fred Pearce, which included a chapter on hydroxyl (“The Last Generation”). Later, in 2011, while participating in a Convention on Biological Diversity civil society meeting on climate geoengineering, attended by various “experts” on geoengineering, Almuth raised the question about how injection of sulfate aerosols might impact OH behavior, but no answer was offered.

The fact that the vitally important question whether SAI might impact on the lifespan and thus the concentration of methane in the atmosphere was never publicly asked or acknowledged by geoengineering advocates until now, is deeply troubling. OH is not something totally new. It has long been known as a factor in atmospheric chemistry, discussed in the IPCC climate science reports for over a decade. The potential for SAI to cause ozone depletion, (which is mediated by OH), was identified, but nothing appears to have ever been written about the potential effects on methane.

Surely, anyone seriously contemplating the injection of massive quantities of sulfur into the stratosphere SHOULD have taken careful consideration of the impact that doing so would have on all of the OH–mediated chemical reactions, including methane.

This apparent oversight could be viewed as a textbook example of how a severely narrow, reductionist engineering world view fails us. The complex interdependence of multiple, ever-changing, physical and chemical factors that results in our life-supporting atmosphere is not amenable to understanding in linear, binary, widget-tweaking terms. We can at least hope that it was in fact an “oversight” and not deliberate shrouding of the issue: potentially the impacts on methane longevity could entirely offset any purported cooling from SAI – or worse. One methane molecule is estimated to cause 28 times as much warming over a century as one CO2 molecule. This new “risk” thus utterly undermines proclamations (grants, careers and all) of its’ effectiveness as a means of cooling.

Had SAI already been deployed, we might now be learning the hard way via experience about OH/methane interactions. Or even worse, even if the effects were exactly as predicted by the models used in the recent study, there would be so many other possible reasons for rising methane levels that it could still be difficult to prove the link to SAI. Fortunately, with a de-facto moratorium on geoengineering, (via the Convention on Biological Diversity), widespread deep public skepticism towards climate geoengineering in general, and serious concerns about governance, we have not gone down that road yet. Many are banging the geoengineering drums with increasing persistence however, calling for “desperate measures” as the climate heats up.

This study is an important wake up call. Several prior studies indicated that SAI would be problematic for various reasons – from regional impacts on rainfall and weather, to impacts on ozone. This latest study provides a compelling reason to steer entirely clear of SRM. Virtually all climate geoengineering technofixes that are under consideration not only distract from the urgency of immediate emissions reductions – but also it is clear that they simply won’t work! In fact, deploying any of the proposed geoengineering techniques is likely to only make matters worse. As we race headlong into climate chaos and face calls for desperate measures, this would be a key point to keep in mind!

[1] OH also plays a key role in sulfur chemistry in the atmosphere. See for example:

[2] Visioni, D., Pitari, G., Aquila, V., Times, S., Cionni, I., Genova, G. and Mancini, E. 2017. Sulfate goengineering impact on methane transport and longevity: results from the Geoengineering Model Intercomparison Project.(GeoMIP). Atmos. Chem. Phys., 17: 11209-11226