The complicated potential of geoengineering
Adding iron to the ocean. Releasing aerosol particles into the atmosphere to reflect light. Installing underwater curtains to prevent warm water from flowing towards glaciers. What do these three things have in common? They all allegedly have the potential to stop climate change in its tracks. Called ‘geoengineering’ or ‘climate engineering,’ these ideas propose that through either carbon dioxide removal or solar radiation management, we can mitigate the climate crisis and prevent environmental disasters from occurring. Is this actually a good idea, though? Will these technological advancements actually provide long-term solutions to our rising temperatures?
The first geoengineering solution I was ever presented with was ocean fertilisation. I remember it clearly: writing my notes as my professor explained that the idea behind this solution is that adding small amounts of iron to the ocean can lead to phytoplankton blooms, which in turn, will remove carbon dioxide from the atmosphere. Then, when the phytoplankton sink to the bottom of the ocean, this carbon becomes sequestered. My professor then explained that this was only one form of geoengineering that had been proposed to mitigate climate change. For instance, stratospheric aerosol injection would involve releasing aerosols into our atmosphere to reflect more solar radiation. Sitting in lecture, writing my notes on this aerosol injection plan, all I could think of was the movie Snowpiercer. These solutions sounded like something out of science fiction: an amazing technological advancement that could instantly fix all of the issues I feel paralysed about in the middle of the night. When I went home and started to look up these solutions, each one seemed more out of this world than the last.
The benefits that geoengineering proposes are, in simple words, insanely amazing. Models show that by using solar radiation management solutions alongside cutting carbon emissions, we could stay well below the 2° Celsius threshold. This also means we would see a reduction in storm intensity and changes in water availability. Other geoengineering solutions also show potential benefits that could help mitigate the negative impacts of the climate crisis. Ocean fertilisation would remove carbon dioxide from the atmosphere and thus limit the negative impacts of climate change. Brightening marine clouds by essentially spraying saltwater into the air over the ocean to reflect the sun’s radiation could help offset global warming and potentially help prevent further sea ice loss. All of these technologies promise huge gains in removing carbon from the atmosphere or shielding our Earth from warming radiation. Along with cutting our carbon emissions, these solutions may be helpful in preventing the climate crisis from worsening.
Reading the article up until now, you may be thinking, “Silas, where is the issue! These solutions seem awesome, like they are from an H.G. Wells science fiction book!” I would initially agree; they truly do sound fantastical. However, along with all of the benefits they bring, geoengineering solutions also bring side effects that could drastically alter our world. One issue, even from an initial glance, is that these solutions don’t address the core issue of our crisis. The climate is not changing randomly; it is a direct result of our continued carbon emissions. These geoengineering technologies do not prevent us from continuing to pump carbon dioxide and other greenhouse gases into the atmosphere. Rather, they represent a band-aid solution to the crisis instead of getting to the root issue. Moreover, solutions like aerosol injects ignore other impacts of climate change like ocean acidification.
AGU, a group for professionals in Earth and space sciences, put out a statement recognizing that these geoengineering interventions should be done alongside reductions in emissions. However, even if we switched to wind turbines as we pumped the sky full of aerosols, there are still numerous side effects we haven’t addressed. To continue with the example, consider stratospheric aerosol injection. Researchers from NOAA CSL and CIRES, collaborating with Cornell and Indiana University, found that the outcome of injecting SO2 into the atmosphere was not just cooling temperatures. They saw impacts on the stratospheric ozone layer (which we have spent years trying to repair, may I remind you), large-scale circulation patterns, and regional weather and precipitation. While these negative impacts could be reduced if the SO2 is released near the poles, there are still other issues with this solution. Another study from Rutgers University found that if we stopped the release of aerosols eventually, global temperatures would just rise again and leave many species unable to adapt to the rapid change. This means that even if we used stratospheric aerosol injection as a short-term solution to buy us time to lower our emissions, we may see impacts when we stop releasing SO2 in the long term. Other solutions such as ocean fertilisation also have the potential to have negative cascading impacts. Beyond not preventing other issues that we see in our oceans due to climate change, this solution can lead to eutrophication (and eventually a reduction in oxygen levels), changes in the presence of phytoplankton species, and potentially even impact the distribution of nutrients globally in the oceans. These are all huge issues that alter entire ecosystems or even the physical processes of the climate.
The Intergovernmental Panel on Climate Change has recognised these limitations. They also see the many political, ethical, and practical issues of geoengineering, which contribute another layer of issues to these ideas. The group, however, also recognises the importance of removing CO2 from the atmosphere and the utilisation of alternative solutions as we move towards reducing our emissions. For this reason, geoengineering as a solution to climate change is not a black-and-white issue. Its future is complicated; we have to weigh whether the positives of reducing surface temperatures while we transition to green energy sources are worth the negative effects geoengineering can have on our ecosystems.
This article is not to say that we should abandon all hope, or abandon all geoengineering solutions. Anything that helps us limit the impacts of the climate crisis is important, but these far-fetched ideas born of science fiction cannot be our only option. We have to transition away from fossil fuels and reduce our emissions now, not later. Band-aid solutions won’t fix the changing climate.
