CE Legal Standpoint

No RM research without investment in emission avoidance

Are any of the above arguments convincing? It is true that every tonne of CO2 released today increases the pressure on future generations to act. If global warming is to be limited to below 2 °C by the end of the 21st century, they will have to remove more CO2 from the atmosphere in an even shorter space of time. The task thus becomes bigger the longer effective climate action is delayed.

Some experts – not least given the moral hazard mentioned earlier – consider it unethical to use the possible need of future generations as an argument to begin developing RM methods now rather than resolutely implementing measures to reduce emissions. Anyone who is not prepared to adapt their own lifestyle to help meet the climate targets should not use the argument of safeguarding the future to justify investment in the research and development of RM. This approach is also referred to as the conditionality argument: A state should, therefore, only be allowed to embark on RM research and development if it meets certain climate policy conditions relating to its climate policy integrity and credibility. Given the risks mentioned and the hubris trap, which stakeholders can in all good conscience be entrusted with RM methods, and who gets to decide? This has led environmental ethicists working on the DFG Priority Programme to develop a principle on which RM research should be based: States may only conduct research on radiation management if they pursue ambitious climate policies and make appropriate contributions to international carbon offsetting funds. This conditionality argument relates first and foremost to field research at various scales, whereas laboratory research and modelling are subject to the principle of academic freedom.

Emergency scenario: Playing with fire

Arguments in favour of the use of climate-regulating RM in emergency situations must also be subjected to critical appraisal. The decisive question here is: What constitutes a climate emergency? An emergency does not simply exist or occur – it has to be declared. The ‘tipping points’ in the climate system are often cited as examples. These are far-reaching changes in the climate as a result of which the living conditions of many millions of people would worsen. They include the melting of the West Antarctic ice sheet, weakening of water mass circulation in the North Atlantic and the disruption of monsoon rains in West Africa.

It appears that interventions in the Earth’s radiation budget could indeed reduce the increase in the global mean temperature at least for the duration of RM deployment. It remains questionable, however, whether radiation management would be able to prevent some of the tipping points mentioned from being reached. On the one hand, the changes will probably already be in full swing before we even notice the first clear signs of a tipping point. On the other, given the inertia in the affected processes, even drastic measures might no longer exert any real influence in a given situation. It would then be practically impossible to prevent a tipping point from being exceeded. In other cases, however, the slowing down of the temperature rise could lead to a weakening of dangerous feedback processes. A rapid cooling of the Earth could, for example, stop the Arctic permafrost from thawing and thus prevent the release of large quantities of methane stored in the ground.

It would in any case be naïve to believe that debate surrounding an emergency connected with drastic changes in climate and related tipping points could be conducted solely on the basis of scientific facts. A state of emergency always has to be declared politically. Doing so presupposes agreement in society about the conditions for making such a declaration. Will a rapid rise in sea levels or years of drought in certain regions warrant declaration of a climate emergency, or will political and social unrest be needed as well? When is an event or situation deemed so bad that it must be interpreted as an emergency that legitimises the use of radiation management methods? For example, would the New Orleans floods caused by Hurricane Katrina have been enough for a planetary climate emergency to be declared?

In reality, different values, perceptions and interests always play a role when assessing exceptional situations. The decision to declare a state of emergency – whether climate-related or not – is always a political act in the course of which political interests are pursued. One particularly alarming aspect in all of this is the fact that emergency situations can cause democratic principles to be forgotten or ignored. In this way, they give certain people power and options for action that they would not have without a state of emergency or that in normal circumstances would be unlawful. For this reason alone, philosophers, environmental ethicists and social scientists warn against taking up the argument of emergency response in the CE debate without prior critical appraisal.


Using radiation management to buy time – but on three conditions

Despite all this, the idea of being able to use radiation management to reduce the temperature quickly and effectively also gives rise to hope. It could enable humanity to buy the time urgently needed to develop technologies for emission-neutral lifestyles, implement climate action and remove sufficient quantities of carbon from the atmosphere. Some scientists believe that this approach is the only convincing argument in favour of deploying RM methods, but they attach three conditions to any form of application.

→ First, a clear deployment strategy would be needed, based on extensive scientific evidence. However, given the lack of relevant research to date, much research and testing would have to be done in the coming decades before humankind could actually intervene in the Earth’s radiation budget to any great extent. It would be necessary to move quickly from small-scale experiments to large-scale trials, with a fluid boundary between experiment and trial.

→ Second, applying the conditionality argument, any deployment would have to be accompanied by major investment in emission reductions and environmentally compatible CDR measures so as not only to combat the symptoms of global warming, but also its cause.

→ Third, for intergenerational equity, the deployment would have to be for a limited time from the outset. The initiators of radiation management measures would therefore need a clear exit strategy whose implementation would have to be monitored. The phase-out should not be abrupt, but gradual. The ‘buying time’ argument thus presupposes great moral and political trust in the implementing actors.

Summing up at this point, it can be said that two basic insights should be taken into account when considering climate engineering. First, use of CE methods cannot and must not be a substitute for vast reductions in greenhouse gas emissions. The guiding rule must be that the causes of problems have to be resolved. Second, the use of CE methods does not put an end to shifting risks into the future. On the contrary, in certain circumstances the use of CE can even increase the risks for future generations. In principle, these insights apply equally to CDR methods with non-permanent CO2 sinks and to the use of RM. The various CDR and RM methods continue to have different specific risk profiles. A drastic reduction in emissions, combined with ecological restoration and adaptation assistance conducive to the SDGs, could lead to a lower-risk future scenario. From an (environmental) ethics standpoint, this scenario would deserve to be given greater attention in science and policymaking, and to undergo priority study with a view to potential and side effects.

Do legal arguments speak for or against the use of climate engineering?

The fundamental question as to whether researching into and deploying CE methods is lawful has to be assessed on the basis of international law to the extent that the impacts of a CE experiment or its use cannot be limited to the territory of the state involved and its effects would also be felt in neighbouring states or beyond.

Under international law, there are so far no rules that generally and comprehensively regulate climate engineering research or deployment. It is also considered unlikely that the international community will one day produce a comprehensive international agreement on climate engineering. National interests and CDR and RM methods differ to far too great an extent. There is not even a binding definition of climate engineering in international law: Whether or not specific CE methods are lawful is instead assessed method by method based on the relevant international agreements and customary international law.

This case-by-case approach has two advantages: First, the legal assessment is based on the facts of the specific case. This means, for example, that a planned CDR or RM project will always be evaluated on the basis of a specific agreement governing the relevant subject matter. For iron fertilisation projects, this would be the Protocol to the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (London Protocol, see SPOTLIGHT: International Agreements). In the case of CE experiments involving cloud seeding, the relevant agreements would be those on long-range transboundary air pollution and protecting the ozone layer. The second advantage is that the international community is more willing to adapt existing international law to new requirements if this is done cautiously, one step at a time. Without a large majority or even consensus among nation states, changes are ruled out.

The Paris Climate Change Agreement commits Parties to establish more carbon sinks and thus increase the storage capacity for carbon dioxide as a greenhouse gas. Carbon dioxide removal methods, such as afforestation and bioenergy with carbon capture and storage (BECCS), are not explicitly mentioned in the Agreement, but are incorporated indirectly. Radiation management (RM) technologies, on the other hand, are excluded because they do not capture CO2. The term climate engineering was avoided when drafting the Paris Agreement

After in-depth analysis of the various CE methods, legal experts conclude that carbon dioxide removal measures tend to give rise to fewer legal concerns than radiation management measures. For all CE methods, however, the state implementing them must at least follow the principle of prevention (this is still contested with regard to the precautionary principle) and have due regard to the existing rights and territorial integrity of other states. This includes, for example, carrying out an environmental impact assessment before deciding on the feasibility of a CE project. If a state were to plan CE measures on its own, meaning without agreement and without prior assessment, and if those measures affected neighbouring states, the measures would contravene international law. But even if a project fulfilled all the criteria, the final decision would still represent a balancing of risks. ◆