CE Ethical Standpoint

Anyone wanting to influence the Earth’s temperature on a large scale intervenes in the planet’s energy and material cycles, and affects socio-political structures in ways that are difficult to predict. This raises the question: Are we allowed to use climate engineering, or do we even have a duty to do so given how global warming endangers both ecosystems and people?

What are the arguments for or against researching, testing and using specific methods? This cannot be answered on grounds of technical feasibility alone. Just because something is possible does not mean it is allowed. Ethicists therefore focus on the moral justification for and evaluation of options and measures. They reconstruct and analyse the arguments for and against. Law scholars, in turn, examine whether potential measures can be reconciled with the prevailing provisions and principles of international law.

Importantly, the ethical and legal arguments apply to carbon dioxide removal methods and radiation management methods in different degrees. The decisive factor in all of this is that the various approaches subsumed under climate engineering differ substantially in their aims, their spatial and temporal scales, their impacts and their associated risks. There are also distinctions between the moral and political issues that arise in light of the different methods used. In many cases, different issues have to be discussed in relation to radiation management than in relation to carbon dioxide removal. For the latter, a further major distinction has to be made between ocean-based and land-based methods. This means that blanket judgments on the admissibility or inadmissibility of climate engineering as a whole are unconvincing and do not help move the debate forward. It is possible to argue in favour of carbon dioxide removal (CDR) and against radiation management (RM) (or vice versa) or perhaps only for one specific method used in CDR or RM.

Always no more than the second-best option

A typical underlying assumption that ethicists examine, for example, is the belief widespread in the 1960s and 1970s that for problems that cannot be solved by policy means, a quick and ideally low-cost ‘techno fix’ must be sought. This argument is based on the assumption that technology can buy the time needed for a policy solution to be found.

Translated into the context of climate engineering (CE), this means that because it will take several decades to achieve full blown transition of the global economy to carbon-neutral energy sources, climate engineering must be given serious thought. There are, however, a number of arguments against the combination of buying time and a techno fix.

False sense of security
One particularly important argument in the debate is that research and development of climate engineering methods involves a ‘moral hazard’ that the risks associated with a rise in greenhouse gas emissions could be increasingly ignored. Along this line of thinking, the theoretical feasibility of climate engineering could give people a false sense of security. Especially with RM methods as a kind of ‘ace up the sleeve’, it would close their eyes to the dangers of climate change. In the hope that the worst can thus be prevented, people would be even more reluctant than ever to change their lifestyles and support the transition to a low carbon economy.

With this attitude, however, humanity would put off the risks associated with the various methods for the future and neglect their responsibility to act on behalf of generations to come. Would it be acceptable to ignore and pass on those risks? If intergenerational equity is to be the benchmark, we must leave our grandchildren and great-grandchildren a world in which their opportunities are no worse than those available to the generations alive today. 

That responsibility applies in particular to the poorer regions of the world. It means humanity must now limit climate change to the greatest extent possible, develop and finance adaptation strategies, and prevent both climate and environment-driven mass human migration. If we are to take our responsibility for future generations seriously, we are also obliged to prevent the use of CE from posing a dilemma for our descendants, who may have to either continue CE methods despite serious side effects or discontinue them and thus perhaps even accelerate climate change. This applies especially to RM methods because RM would not reduce atmospheric greenhouse gas concentrations. Without accompanying CO2 reduction measures, RM methods would postpone the responsibility for finding a solution into the future.

In some cases, however, the same risk analysis also applies to CDR methods, as these too are associated with considerable risks due to scale needed for them to have an impact on the climate. As long as humankind continues to release increasing levels of CO2 into the atmosphere, more and more areas of land and sea will be needed to offset those emissions using suitable CDR methods. For some such methods, especially afforestation, it would have to be ensured over very long periods of time that the carbon that has been stored is not re-released sometime in the future. Given the growing world population and the need to expand food production, land-intensive CDR strategies – such as bioenergy with carbon capture and storage (BECCS) – could prove extremely conflict-prone when it comes to land use. In many cases, land used for CDR is no longer available for food production. The effects of BECCS on land prices, land ownership and thus on the agricultural livelihoods of large numbers of people would also have to be taken into account. In addition, establishing huge plantations of fast-growing grass and tree crops could deplete both water reserves and biodiversity. The question of irrigating BECCS crops alone highlights the resource-related conflicts that could arise, bearing in mind that around 70 percent of global freshwater withdrawals go towards the irrigation of agricultural land.

Is it morally justifiable to maintain our energy-intensive lifestyles and pass on their side effects to future generations? Given the potential for conflict, can we expect climate engineering methods to augment emission reduction? If, with regard to the global climate and to nature, we see equity between present and future generations as the yardstick for our actions, these questions are of tremendous importance.


The hubris trap
The fact that people tend to over-estimate their own abilities speaks against large-scale intervention in the Earth’s climate. This also applies to researchers and engineers. The argument of over-estimating one’s own capabilities is known as the hubris argument. The term ‘hubris’ comes from ancient Greek and means excessive pride or overconfidence.

Even after years of intensive research into the various methods of climate engineering, it would be irresponsible to believe that we humans fully understand and master the effects of these methods on the systems to be influenced – especially as many of the methods have not yet been technically implemented and cannot easily be tested in the field. First and foremost, this concerns the scale of their intended and unintended effects, their socio-political impacts and hence their direct and knock-on costs. It can be assumed that new problems will arise as CDR and RM methods are used over time.

Saying goodbye to the natural world
A third argument against climate engineering results from the question as to the extent to which RM methods in particular would change our relationship with nature. Do technical interventions in the climate mean a final departure from the natural Earth system? The fact that we have changed the world’s climate unintentionally by using fossil fuels does not mean that we have free license to influence it intentionally.
To take deliberate control of climate processes would be to take our confidence in the predictability and controllability of interventions in the Earth’s cycles to the extreme

It is mostly radiation management methods that have so far been discussed as an expression of total human dominance over nature. Measures such as afforestation do not necessarily stand in stark contrast to the idea of nature conservation, which requires that people respect nature and reduce their own impact. It would certainly be possible to combine CDR strategies with strategies for natural adaptation to climate change, biodiversity conservation and ecological restoration. These mainly apply to forests, peatlands and soils and are also referred to as natural climate solutions. However, large-scale restoration measures can also be seen as major interventions in ecosystems. This could also put them in direct competition with other sustainability goals such as food production. If storage of significant quantities of carbon is to be ensured over long periods of time, then even ‘natural’ solutions tend to require active management and hence an intervention in nature.


The problem of goal prioritisation
The United Nations has set out 17 Sustainable Development Goals (SDGs) to ensure sustainable development throughout the world. While one of these is to combat climate change, the UN sustainable development strategy is also about poverty reduction, food security, peace, natural resources and water supply. Implementing the SDGs is a complex task – one that poses a tremendous challenge for humankind. Given the complexity involved, it is self-evident that every CE method has the potential to conflict with the UN SDGs. This applies especially to water reserves, biodiversity and food security. But positive effects are also possible – for example, improving soil fertility by enriching arable soils with powdered minerals (enhanced weathering). CDR methods that realistically promise positive interactions with other SDGs thus deserve greater attention both from the science community and from policymakers.

If CDR or RM methods are used, situations may arise in which – depending on the method involved – goals would have to be weighed against one another. One example would be land-based CDR methods such as cultivating crops for bioenergy or biochar. Large-scale use of such methods could jeopardise both biodiversity conservation and production of adequate food supplies. How to resolve goal conflicts of this kind is hotly debated. In the end, the decisive factors will be the choice of priorities and of who should benefit and who should not. This in turn comes down to values and is thus a fundamental matter of ethics. A policy answer should only be provided on the basis of sufficient ethical arguments. There will be no simple algorithm that can be used to resolve the conflicting goals. This makes superordinate policymaking structures all the more important.

How convincing are the ethical arguments in favour of climate engineering?

Despite these critical arguments against CDR and RM methods, there are also aspects that speak in favour of researching and potentially using them. Put in simple terms, the central arguments are as follows:

 Intergenerational responsibility
The impacts of climate change will primarily affect future generations. This is why we must equip our offspring with knowledge of both CDR and RM methods so they can decide for themselves how to use them when the time comes. This argument is also known as ‘arming the future’.

 Emergency response
We need climate-regulating methods to be able to intervene in the climate quickly and effectively in an emergency. This is known as the ‘emergency’ argument and applies solely to RM

→ Buying time 
By carefully applying RM methods for a limited period, humankind can buy time to use CDR methods in order to effect large-scale reductions in atmospheric greenhouse gas concentrations without further warming in the interim.

→ Lesser evil
If humankind is not able to reduce greenhouse gas emissions quickly enough, the evils involved in using CDR or RM would be less than those involved if they are not used. This is also known as the ‘lesser evil’ argument.