What is geoengineering?
Geoengineering is an umbrella term used to describe a range of technologies that would deliberately and on a large-scale interfere in the Earth’s climate system, to reduce the negative effects of climate change.
While the exact usage of terms may vary, there are two main approaches:
Carbon Dioxide Removal (CDR), also known as Greenhouse Gas Removal, Negative Emissions Technologies (NETs), or Carbon Drawdown, aims to reduce atmospheric concentrations of Carbon Dioxide (CO2) (the primary human source of climate change) through processes that permanently remove them from the atmosphere.
CDR methods include the use of biological ‘sinks’ and chemical processes, and vary considerably in their potential, readiness, permanence, cost, and risks of negative side-effects. These approaches are not all necessarily considered as geoengineering, although deploying them at sufficiently large scale, in aggregate, to alter the climate may be considered as geoengineering.
Removing atmospheric CO2 is not a new idea: the UNFCCC has always considered mitigation to include both emission reductions and removals. What is new is the large scale, nature and urgency of CDR deemed necessary by the Intergovernmental Panel on Climate Change (IPCC) to help limit global temperature rise to 1.5°C. This has important implications for the governance of CDR at global and national levels.
Solar Radiation Modification (SRM), also known as Solar Radiation Management, or Solar Geoengineering, refers to methods that aim to reduce global warming by reflecting more solar radiation into space, or by allowing more heat to escape the earth’s atmosphere. Many conceptual ideas for SRM exist, which vary considerably in their potential, readiness, permanence, cost, societal acceptance and risks of negative side-effects. Most have not yet progressed beyond words on a page, a computer model or laboratory experiment, and none are currently ready for deployment.
Both the research and any potential deployment of either large-scale CDR or SRM would require governance nationally and internationally, to maximize benefits and minimize risk, as well as to ensure costs and benefits are justly distributed.
Why are some people considering geoengineering?
The world is already suffering from the effects of climate change.
Extreme weather events are being attributed with increasing confidence to global warming, as seen in hurricanes in the Caribbean and the Atlantic, forest fires in Europe and North America, droughts in Africa, and floods in Asia.
These events are causing wide-scale suffering. They are also eroding progress towards the Sustainable Development Goals, which world governments agreed to in 2015 as a road map to end poverty, protect the planet, and ensure prosperity for all.
In December 2015 in Paris, world governments agreed to limit average global temperature rise to within 1.5-2°C above pre-industrial levels—beyond which the negative consequences for humankind would become increasingly severe.
To do this, the Paris Agreement envisaged a rapid decarbonization of the world energy system, relying on both emissions reductions and removal of atmospheric CO2, “so as to achieve a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of this century”. But global emissions are still rising, and existing government pledges continue to fall short. A recent report by the Intergovernmental Panel on Climate Change (IPCC) found that achieving the 1.5°C goal requires halving emissions within ten years, as well as removing substantial amounts of CO2 from the atmosphere in order to reach global negative emissions within the second half of this century.
Given the challenging scale of reductions and removals necessary to attain the temperature goal in the Paris Agreement, a number of scientists are suggesting that Solar Radiation Modification (SRM) could be an option to buy more time in the event of temperatures exceeding the Paris goals – but this potential benefit must be weighed against its many risks, both known and unknown.
While work on SRM is mostly limited to computer models and academic papers, there are plans for the near future to begin an outdoor experiment related to one particular approach, known as stratospheric aerosol injection (SAI). According to the IPCC: “although some SRM measures may be theoretically effective in reducing an overshoot, they face large uncertainties and knowledge gaps as well as substantial risks and institutional and social constraints to deployment related to governance, ethics, and impacts on sustainable development”.
As the effects of temperature rise become more apparent, there is concern that some actors could go ahead with research and even deployment of solar radiation modification unilaterally, and without governance. This could cause very serious problems for global ecosystems and the environment, as well as triggering potential conflicts.
Why are many people reluctant to consider geoengineering?
One of the biggest concerns surrounding both large-scale Carbon Dioxide Removal (CDR) and Solar Radiation Modification (SRM) is the potential for “moral hazard”. This is the risk that the potential existence of additional measures to tackle climate change could divert interest away from the immediate priority of reducing carbon dioxide emissions.
Other overarching concerns include a focus on technological solutions to what may primarily be a socio-economic problem, and the risk of stepping into areas which many people consider to be outside the realm of human responsibility (‘playing God’).
There is also concern that some of these technologies may be inherently ungovernable, opening a Pandora’s Box of potentially damaging effects, which could never adequately be made safe or just. This concern is most salient for proposed Solar Radiation Modification (SRM) measures, which the IPCC says face ‘large uncertainties, knowledge gaps and substantial risks’, as well as institutional and social constraints.
While some critics argue for a ban on all geoengineering field experiments and deployment, other observers assert that premature rejection of these technologies could end up being as risky for the well-being of people and the ecosystem we depend on as might their premature use.
Would geoengineering allow us to keep emitting carbon dioxide and still avoid climate change?
No. If geoengineering techniques were to be deployed at all, they would have to be considered as complementary to massive emission reductions and adaptation efforts, which seek to lower the risks from unavoidable impacts of climate change already baked into the system. Carbon dioxide stays in the atmosphere for a very long time, from a minimum of several decades to a millennia or more. There is already enough CO2 in the atmosphere to continue causing the climate to change for hundreds of years.
Any potential deployment of Solar Radiation Modification, were it to be deemed acceptable by society and shown to be viable, would not in itself directly reduce atmospheric CO2, and would need to be accompanied by continued efforts to decarbonise the global economy, as well as large-scale carbon dioxide removal.
What is the current legal status of geoengineering?
While some elements exist for the international governance of large-scale Carbon Dioxide Removal and Solar Radiation Modification, they are neither sufficient nor in force globally. Overall, there is no effective, comprehensive and universally accepted framework governing the research, testing and possible use of large-scale Carbon Dioxide Removal or Solar Radiation Modification.
Since 2009 reports from the UK Royal Society, the European Union, and the US National Academies of Science, and more recently the IPCC Special Report on 1.5°C Global Warming, have highlighted the need to develop this governance.
A number of piecemeal approaches are currently in place. These include:
- Existing provisions under the UNFCCC, the Kyoto Protocol and the Paris Agreement address some aspects of governing large-scale Carbon Dioxide Removal, but many key governance gaps and challenges still need to be addressed;
- Some decisions under the Convention on Biological Diversity have established a framework for considering the use of geoengineering;
- Amendments to the London Convention/London Protocol have addressed marine geoengineering, such as ocean fertilization, in a risk management framework.
Given the potentially planetary-wide effects of these approaches, it’s essential that this governance gap be closed, and that there be a transparent, inclusive public discussion on how the world governs geoengineering.
What does C2G2 see as the top priorities for geoengineering governance?
In order to catalyze the creation of effective governance for Solar Radiation Modification and large-scale Carbon Dioxide Removal, following wide-ranging discussions with experts in governance and geoengineering from across the world, C2G2 established three priorities:
- Governance of Solar Radiation Modification. C2G2 will catalyse international agreements to help prevent the deployment of Solar Radiation Modification unless (i) the risks and potential benefits are sufficiently understood, and (ii) international governance frameworks are agreed.
- Governance of Research. C2G2 will support the development of international governance of research, particularly for Solar Radiation Modification.
- Governance of Carbon Dioxide Removal. C2G2 will encourage discussions about the governance of large-scale Carbon Dioxide Removal at the appropriate sub-national, national and global levels, including in particular at the UNFCCC.
Who needs to be involved in the debate on geoengineering governance?
Until recently, the debate around large-scale Carbon Dioxide Removal and Solar Radiation Modification was mostly limited to scientific circles. This is changing, but not fast enough. Policy makers and civic representatives worldwide need to get more involved.
Many key players are understandably concerned that discussing geoengineering could weaken support for radically reducing carbon dioxide and other greenhouse gas emissions. But this view is evolving, as the sheer scale and urgency of the climate challenge becomes apparent.
The Intergovernmental Panel on Climate Change (IPCC) Special Report on Global Warming of 1.5°C warned that reducing emissions was no longer enough to achieve that goal, beyond which climate change becomes increasingly dangerous. Some degree of large-scale Carbon Dioxide Removal (CDR) will also be necessary. This has opened the door for more policy makers to talk about CDR, although that conversation is at an early stage.
As the challenge of both cutting emissions and removing CO2 becomes increasingly apparent, there has also been growing consideration of Solar Radiation Modification (SRM) to potentially buy more time, although the deployment of SRM is still not being proposed by any major actor.
Leaders as well as the public need to acknowledge the growing risks of both action and inaction in a deepening climate crisis. A wide range of communities would need to be involved in any decisions on the large-scale testing or deployment of geoengineering approaches. Policy makers need to consider the governance implications before events overtake.
- Scientific and Academic Community. Scientists and academics have driven the debate on geoengineering for the past decade, and published hundreds of papers. The UK Royal Society and the US National Academies of Sciences have recommended that geoengineering needs to be governed. For the most part, however, this debate has been concentrated in a small number of countries.
- Civil society organisations (CSOs), including environmental groups. Following the IPCC Special Report on Global Warming of 1.5°C, a growing number of CSOs are addressing the potential risks and benefits of large-scale carbon dioxide removal, including how to govern it. There has been more reluctance, however, to initiate debate on solar radiation modification. If CSOs want to ensure their voices are heard, it makes sense to get involved earlier rather than later in policy discussions, before others have framed the debate.
- Faith Communities. Geoengineering touches on profound questions around humanity’s relationship to the environment and the cosmos. For many people, this has been the province of religion rather than government or science; any serious discussion must include representatives from a wide range of religions and philosophies.
- Governments and Intergovernmental Organizations (IOs). Governance of geoengineering needs to take place at multiple levels, nationally, regionally and internationally. Interest by governments and international organisations is growing following the IPCC special report on 1.5°C. This is driven by growing concern over the rising impacts of climate change, and insufficient global progress in limiting warming to 1.5–2°C. But more governments and IOs need to get involved, in order to build a comprehensive and effective governance framework.
- Media is likely to play a large role in public perceptions of geoengineering and its governance. Specialist and mainstream media interest in carbon dioxide removal has grown following the IPCC special report on 1.5°C, and as more societal players explore its potential. Solar radiation modification has remained more of a niche interest, but attention is growing and will rise further if decisions are made and experiments begin. On social media, there is widespread discussion of what many see as a ‘chemtrail conspiracy’. Scientists agree this conspiracy does not exist, but the belief that it does can influence the public debate.
- Cultural Leaders. Geoengineering has not fully broken through into mainstream debate, but sci-fi movies from Hollywood as well as from China and reflect growing popular concern over climate change and poorly governed interventions to tackle it. Musicians, artists, writers and filmmakers have an important role in exploring the challenges of a geoengineered world.
- A growing number of entrepreneurs are creating start-up efforts to remove atmospheric CO2, often as offshoots from scientific work. Some corporations, including fossil fuel companies, are also exploring the development of CDR technologies, but for many, the business case has proved elusive, absent a price on carbon. Policy incentives may be needed to scale up any technologies society deems sufficiently safe and acceptable.
Where has Carbon Dioxide Removal recently been discussed?
In 2018, two key events raised the profile of geoengineering, in particular large-scale Carbon Dioxide Removal (CDR).
- In October 2018, the IPCC released a special report on global warming of 1.5°C found that “all pathways that limit global warming to 1.5°C with limited or no overshoot project the use of carbon dioxide removal (CDR) on the order of 100–1000 GtCO2 over the 21st century.”
- The UNFCCC’s COP24 in December 2018 saw a significant number of side events address large scale Carbon Dioxide Removal, although it was not on the delegates’ core agenda.
Where is the geoengineering conversation headed?
The conversation around large-scale Carbon Dioxide Removal is expected to intensify, following the IPCC’s latest finding that all pathways to limit global warming to 1.5°C require its use. Discussion will focus on which methods should be pursued, how much, where and how to pay for it, as well as other important governance questions including permanence of storage, safety and liability and compensation.
At the same time, the urgency and immense challenge posed by the global societal transformation required to reduce and draw down CO2, particularly given slow progress to date, is likely to prompt more interest in Solar Radiation Modification (SRM).
Important moments could include:
- The fourth meeting of the UN Environmental Assembly (UNEA-4) in March, which will consider a draft resolution expanding global knowledge of geoengineering technologies and their governance;
- Depending on the outcome of UNEA-4, the UN Environment Programme may be called upon to prepare a global assessment of geoengineering;
- The potential start of outdoor experiments on Stratospheric Aerosol Injection (SAI) could prompt a wider conversation about these technologies.
Is geoengineering the same as weather modification?
C2G2 does not consider geoengineering to be the same as weather modification, primarily due to differences in scale, duration and intent.
At the same time, large-scale weather modification projects (or the aggregate effect of many weather modification activities) might have effects on regional climates, and lessons learned from their governance may have impacts on the governance of geoengineering as well.
Is Carbon Dioxide Removal the same as Carbon Capture (and Storage)?
No, but in some circumstances, they are related.
In general, carbon capture and storage refers to capturing CO2 emissions from fossil fuels where they are burned (at source), and then storing them permanently underground. Ideally, this would have a net zero impact on CO2 concentrations in the atmosphere.
Carbon Dioxide Removal demands a net negative impact on CO2 in the atmosphere. One proposed approach involves combining biofuels (whose growth would draw down CO2) with carbon capture and storage, creating an overall negative effect.
There are other carbon dioxide removal approaches which do not rely on carbon capture technologies.