Geo-engineering: The Next Step?

By GLOBUS Correspondent Vlasits Eszter

Imagine a movie set sometime during the 21s century, where humanity is on the brink of destruction because of climate related catastrophes. Their last hope was a team of scientists who launched rockets into the atmosphere in the hopes of controlling the weather. But they never expected what happened next. The chemicals froze the whole planet, burnt it up and genetically modified animals, creating monsters. Sound familiar? That is because the chances are that you have seen at least one movie with this plotline. 

Strangely enough neither the plan, nor the possible complications, nor the scientific background are complete nonsense in these movies (well okay, maybe the science part is). Tackling the massive global issues related to climate change with geo-engineering is a common theory, as it is now relatively widely accepted that even if emissions are reduced quickly and drastically, climate change will still have extensive effects on the planet. Humanity is now in a phase of technological advancement where engineering the climate on a scale that it overwrites natural forces is becoming feasible. The IPCC has been looking at this possibility and concluding that it very well may become necessary in order to protect humanity and its environment, and declared it as a ‘Plan B’ for keeping temperature rise under 1.5C. At the same time though, they are aware that geo-engineering is a hugely controversial topic, owing to its experimental nature, unpredictable consequences, difficulties in technological implementation and international organization, and even ethical dilemmas.

How do we engineer Earth’s climate?

So, what exactly does it mean when we say, ‘engineering the climate’? Numerous different technologies are being developed or are already under small-scale implementation. They can be divided into two main groups, carbon-dioxide removal (CDR) and solar radiation management (SRM). First, let’s look at CO2 removal, which is the process of separating harmful emissions from the atmosphere and storing it underground. The most established out of these technologies is Bioenergy with Carbon Capture and Storage (BECCS), which is the process of extracting bioenergy from the renewable resource of biomass, thus effectively removing carbon from the atmosphere and directing it to geological storages where it does not take much energy to keep it. This technology is already being used, but there are doubts about whether it can be sufficiently upscaled. Ocean fertilization is vastly different from this, but it also aims to reduce CO2 levels. The process involves adding nutrients into the water to drive up phytoplankton activity. This would mean that the ocean is able to ‘take in’ more CO2 without the devastating effects of acidification. There are many more methods of CDR, some more feasible than others, but the common (technical) difficulty is the ability to apply them on a global scale.

The other main direction geoengineering is expanding towards is solar radiation management, which is more controversial than the previous methods because it has the potential to be very dangerous. It also does not deal with the root causes of climate change but only mitigates and reduces the consequences of it. SRM does not tackle the amount of greenhouse gases in the atmosphere, instead it searches to block radiation from warming the Earth. These types of engineering solutions concentrate on the warming caused by sun rays and try to physically block it, reducing its effect. Here, a few of the most known approaches are introduced:

• Stratospheric Aerosol Injection: Probably the most researched geoengineering method, with a high probability of successfully limiting warming below 1.5C. SAI recreates the effect experienced in the event of a huge volcanic eruption: various gases seep into the atmosphere, staying there for weeks or even months, visibly limiting the ability of sun rays to get through and reach the surface. During the engineering process, gases (possibly sulfur dioxide and hydrogen sulfide, but there is no consensus yet on what would be the most effective) would be injected into the stratosphere with special aircrafts, resulting in a layer that counters most elements of the modifying climate. The injection would likely not be a one-time event, and constant monitoring and assessment will be needed to determine the time of re-injections. 
• Ground-Based Albedo Modification: The goal here is to enhance the albedo of the planet’s surface, making it absorb less light and reflect it instead. Plans range from clearing boreal forest to give way to icy surfaces and covering natural formations with reflective material to simply painting things white. 
• Marine Cloud Modification: This involves spraying sea water mist in the air above the ocean. This mist will mix with marine stratocumulus clouds and condense into droplets which reflect the sunlight – slowing the temperature rise of water bodies.
• Cirrus Cloud Thinning: Cirrus clouds consist of ice crystals and trap long-wave radiation in the atmosphere. CCT technology would inject ice nuclei into certain parts of them, creating larger ice crystals which will allow more radiation to be transmitted into space. 

A necessity or a recipe for catastrophe?

Though these methods all sound promising, strengthening our sense that all will be well concerning climate change once we apply the amazing technological knowledge humanity has come to possess. However, geo-engineering has a lot of issues. Firstly, the science behind almost all the aforementioned methods is only based on uncertain, theoretical models, owing in large part to the fact that climate change is unpredictable in the most complicated ways. Global warming has uncountable components and their interactions are ever-changing – as a result, even now, without geo-engineering complicating things it is extremely difficult to create accurate predictions, and predictions are crucial when trying to decide on a sufficient course of action and policies. Imagine this whole process with chemicals added to our environment based on an experimental theory with the capacity of going rogue! There is also a fear that the practice (especially SAI) needs to be sustained. Thus, we would be forcing future generations to continue geo-engineering and if we or them stop the process, the termination shock could very well cause catastrophes described in apocalyptic movies.

Secondly, there is a complex social and political side to climate engineering. Based on the current barely existing ‘will’ of governments to cut emissions, it is more than imaginable that geoengineering is going to be seen as a substitute, fixing problems while we continue to exploit, consume, and emit. As with most projects of this scale, international cooperation is absolutely necessary, as many methods cannot be implemented locally, or if they can, they will inevitably affect neighbouring countries. If international regulation fails and the parties become hostile, geoengineering will turn into a powerful weapon, able to destroy ecosystems, economies, and lives. On the social side, when they slowly become a more commonly discussed topic, these technologies will become one of the most controversial subjects in the eyes of the public. A fear of danger and unnaturalness will surround it, similar to the stigma around GMOs and should any of it be implemented, people will raise their voices.

Besides these very tangible difficulties, geoengineering also offers an ethical dilemma. It is not baseless to argue that humanity does not have the moral right to purposefully modify the climate, creating immense consequences for the entire biosphere and every natural process. This is playing God, but without omnipotence, without the control over whatever these actions result in; and should it go wrong, the results will be more catastrophic than anything we have done before. On the other hand, we also have a moral obligation to try and fix what we have already messed up, because we have already purposefully modified the climate, only not because of a need, but because we wanted to benefit from it. Those in favour of geoengineering say that a 100% effective, safe and predictable method of combating climate change will not fall into humanity’s lap. Trusting in this will only result in not taking the more uncertain steps which could nevertheless save the lives of millions of organisms on this planet.

Geo-engineering is now an extremely controversial method, and it can clearly be seen why. But in the end, when things get desperate, it could make or break our success in the fight for a liveable planet. The question is: when will the scales tip to the point where the risk is worth taking and how exactly will humanity carry out the task?

Header Image by Erwan Hesry via Unsplash