Geoengineering: Solution to fight climate change?

Why geoengineering should still be approached with extreme caution or not approached at all

Also known as climate engineering, geoengineering refers to the intentional human interventions used to manipulate the Earth’s climate and counteract the effects of global warming. Despite the fact that a lot of people might never have heard about it before, geoengineering has been a hotly debated topic in the scientific community for several years and has resurfaced in recent United Nations’ Intergovernmental Panel on Climate Change (IPCC) reports. This is possibly due to the inability of current governments, including the Cypriot government, to deal with the increasing carbon dioxide emissions and the fact that the world is at the moment far off course from achieving the Paris Agreement goal of limiting global warming below 1.5°C. According to their 2018 report, the IPCC considers geoengineering to be a possible Plan B in the case that warming exceeds a manageable level; however not all geoengineering solutions are equally accepted.

The geoengineering umbrella traditionally incorporates two main strategies: a) Carbon Dioxide Removal (CDR) and b) Solar Radiation Management (SRM).

Carbon Dioxide Removal (CDR)

CDR is the strategy that is mostly accepted as it tackles the main cause of climate change by removing greenhouse gases out of the earth’s atmosphere. The IPCC already considers CDR within its models for deep decarbonisation. The most prevailing process is using biomass energy to capture carbon and storing it underground (bioenergy with carbon capture and storage – BECCS).

Alternatively, Direct Air Capture (DAC) is another process and involves directly collecting carbon dioxide from the air and storing it. A company in Switzerland called ClimeWorks actually unveiled such a carbon capture plant which is able to directly collect 900 tonnes of carbon dioxide from the air and then sell it as a raw material to other markets. The two aforementioned techniques could prove valuable for negative emission technologies. However, the cost of building such plants, the energy required to power them and the competition for land and water resources affects their upscaling.

Other CDR possibilities are soil carbon sequestration, afforestation and reforestation and ocean fertilisation.

Evidently, CDR strategies could play a significant role in reducing carbon dioxide levels and mitigating climate change, especially if they are implemented alongside other decarbonisation technologies.

Solar Radiation Management (SRM)

Moving on to the more contested type of geoengineering, SRM projects do not reduce greenhouse gas emissions but instead try to reduce their impact by reflecting sunlight back into space. These suggested projects are based on theoretical models which remain untested, especially on a large scale, and entail great risks and a huge amount of uncertainty for potential consequences. The 2021 IPCC report identifies two main approaches of SRM, Stratospheric Aerosol Injection (SAI) and Marine Cloud Brightening (MCB).

SAI has to do with injecting a large number of particles like sulphur dioxide or calcium carbonate into the stratosphere in order to reflect solar radiation back into space. The idea is based on mimicking the effects of a volcanic eruption. However, as we have seen previously with strong volcanic eruptions this can lead to large-scale weather problems in other countries as well. For example, implementing such a project in one country can alter precipitation patterns in another one, or even lead to extreme weather events. Moreover, ozone depletion could occur due to the pumping of sulphur dioxide. Therefore, potential unexpected consequences might occur, while the uncertainty of not knowing what will happen after using and then stopping such an SAI project is also a huge intergenerational injustice issue since future generations would not have consented to carry it out.

Alternatively, Marine Cloud Brightening (MCB) is about spraying seawater droplets into marine clouds for them to become thicker and thus more reflective. According to simulations, this strategy could work especially in order to lower temperatures at a more local level. However, similarly to SAI, it remains uncertain what the impact could be in other locations and if meddling with cloud formation will lead to more rainfall in some areas and less in others, leading to other associated socio-economic problems.

The IPCC suggests that SAI and MCB could work to mitigate global warming and that the technology to do it more or less exists, but the scale it needs to be implemented in and the potential consequences it could have in different locations pose a lot of risk. Moreover, a governing body needed to take such an international decision does not yet exist and it would be completely unjust for a single country to implement a project that could potentially have an impact on countries elsewhere. Thus, the ethical considerations and governance issues to take into account for SRM strategies are quite a big hurdle in their effort to become a solution to climate change.

More importantly, creating a false sense of salvation based on untested and extremely risky strategies at a time when decision-makers should be taking serious action to mitigate climate change, could lessen our chances for survival.

SRM solutions are in my opinion a climate justice topic as, if powerful people decide for their implementation, they would essentially be playing God, deciding to control the earth’s climate in the same way they have led to its ‘slow death’ after the industrial revolution, without taking into consideration local communities, less powerful states, wildlife, and future generations.

Discussing geoengineering and especially SRM solutions as a last resort strategy to save humanity always brings to mind the movie ‘Don’t Look Up’ where world politicians avoid taking action in time and leave their hopes to a technological fix which proves to be ineffective in the end.

So always remember that there is no plan(et) B for us and that the Earth would survive even if we do not.

Pavlos Kailos has a BSc degree from the University of Glasgow and is currently an MSc student in sustainable development at KU Leuven. in Belgium