In 2019, the world emitted the highest quantity of greenhouse gases (GHG) in recorded history. While many are optimistic that there is still time remaining to change our ways, change has been slow, and the large-scale impacts of climate change are becoming apparent.
If we hope to keep to the Paris Climate Agreement goal of halting global warming at 1.5°C above pre-industrial temperatures, the entire world needs to cut its GHG emissions in half by 2030. However, in 2019, GHG emissions increased by 0.6 per cent from 2018, according to the Global Carbon Project.
Rob Jackson, a professor of Earth system science at Stanford University, summed it up nicely in an interview with ***the Washington Post: “We’re blowing through our carbon budget the way an addict blows through cash.”
We have a limited amount of GHGs we can pump into the atmosphere. At the current rate of GHG gas emissions, around 1,332 tonnes per second, the Mercator Research Institute’s Carbon Clock estimates we have seven years and nine months before we reach 1.5°C warming.
Five years after The Paris Climate Agreement was signed there have been improvements, but few countries reach the level of action that needs to be seen to meet the goals of the agreement. If mitigation alone is not enough, or our predictions prove too moderate, drastic measures may need to be taken in the future to reduce catastrophic consequences of climate change.
Geoengineering is a field of research that looks to develop technological solutions to large-scale, environment-related problems. It is the engineering of the Earth, and currently, geoengineers are looking for solutions that can reduce the effects of climate change.
The technology researchers are developing and testing is on the level of science fiction, both in scale and in function, but isn’t. The technology is being actively being proposed as a potential aid to mitigation actions in the fight against climate change.
Students going into nearly every field are going to be faced with critical and challenging questions about climate change actions. Policy makers, both those involved in government and individual companies, will need to make choices about the extent and type of action to take regarding climate change. Those in research will be asked to implement and monitor these solutions.
It can be easy to push for a solution that appears to have the potential to help reduce the impacts of climate change with limited impact on our current way of life. However, major questions around the ethics of intentional, large-scale climate-altering technology and the feasibility of implementation are at the forefront of geoengineering as its solutions grow more and more plausible.
Broadly speaking most ongoing research in the field of geoengineering is divided into two categories: technologies that capture and hold carbon and technologies that manage the sun’s rays.
Technologies around carbon dioxide removal (CDR) look to directly reduce the actual greenhouse gases in the atmosphere. Technologies range from already implemented to entirely theoretical. They are generally more accepted than the proposed technologies of solar geoengineering, and there has been increasingly open discussion on using CDRs as possible climate change mitigation options.
The Intergovernmental Panel on Climate Change (IPCC) publishes periodic and influential assessments of climate change aimed at policymakers. In one of their more recent reports, “Global Warming of 1.5°C,” all scenarios that would limit warming to 1.5°C would require the use of CDRs, and scenarios where the global temperature would need to be reduced to 1.5°C required considerable use of CDRs.
The increase in acceptance of geoengineering as a possible, if not required, solution to climate change is rapid. In 2013, an article in ***the Guardian expressed surprise that the IPCC Fifth Assessment Report even mentioned geoengineering.
The wider acceptance of CDRs may be due in part to the range of technologies that it can include. Afforestation and reforestation fall under the CDR umbrella as carbon capture and storage techniques. Forests act as carbon sinks: plants in the forest take in carbon dioxide through photosynthesis and store it. Forests are dynamic entities, and the carbon captured by trees and plants is converted, reused, and recycled throughout the ecosystem. Though some of it is released back into the atmosphere, much is also stored as carbon compounds in the soil or deep underground as carbon fossils.
There are ongoing reforestation efforts worldwide, and the benefits of replanting deforested areas with diverse native species, and then leaving it to recover, are generally agreed upon.
Afforestation is a more contentious method, which involves planting forests in areas where there historically haven’t been forests. Certain areas don’t need forests, such as the grassland biomes in Africa, an area recently targeted by the Bonn challenge as part of their goal to plant 150 million hectares of forests by 2020, and 350 million hectares by 2030. Grasslands are complex ecosystems in themselves, and the animals and plants that live there have evolved to survive in those circumstances. Planting trees dramatically changes the ecosystems and what species can live there.
Biodiversity is also often ignored, both in reforestation and afforestation efforts. Forests are a complex and dynamic interaction between animals, insects, fungi, shrubs, and trees. Often though, only trees are planted in areas targeted by afforestation efforts, and are limited in diversity. A study published in ***Environmental Research Letters found that biodiverse forests are likely more effective at longer-term carbon storage than plantations, areas of planted trees that often contain few unique species.
The most contentious side of CDR technology is bioenergy with carbon capture and storage (BECCS), a process where biomass is burned for energy, and the carbon produced is captured and stored. Concepts generally involve the growth of crops or trees which use and store carbon from the atmosphere, and are burned for energy to produce electricity or create biofuels.
This technology is still mostly in the development stage, but a number of problems are being discussed, and public acknowledgement of the rather niche technologies is growing. In the IPCC’s above mentioned report, three of the four pathways that limit global warming to 1.5°C included the use of BECCS to a certain degree.
A 2019 study published in ***Nature looked at the public’s perception of BECCS. Participants overall showed an initial high support for research, development, demonstration, and deployment of BECCS with no strong opposition, but support later decreased in groups where researchers discussed potential direct costs to taxpayers and energy users.
Participants also brought up a number of concerns with BECCS — concerns echoed in other research. The amount of land needed for these technologies may be substantial and take away from food-producing agricultural lands. Currently, the technology is expensive and does not scale up effectively. As with CDRs and geoengineering in general, participants expressed concern that looking to geoengineering technology for solutions could marginalize the main solution to reducing the effects of climate change: reducing our GHG emissions. Certain geoengineering solutions could be seen as easier than the development and implementation of green technology and habit changes.
The other main category under geoengineering is solar geoengineering, or solar radiation management (SRM). By far the most likely technology to appear in a science-fiction novel, SRM seeks to mitigate the effects of climate change by directly interacting with the sun’s rays, often using technology to reflect the rays away from Earth.
Greenhouse gases within the Earth’s atmosphere reflect the sun’s rays back to the Earth, keeping them within the atmosphere, and causing warming. Simply put, less solar energy reaching the Earth theoretically equals less warming.
Some of the more unique ideas in this field range from launching a giant reflective surface into space (which is prohibitively costly) to growing crops with a higher albedo, giving large areas of land reflective capabilities while still providing food for the masses. Altering the clouds has also been suggested. Clouds over the ocean could be injected with salt water, increasing their density and therefore their reflectivity.
Of SRM technologies, stratospheric aerosol scattering is one of the most widely discussed and debated ideas, and is considered by some to have potential for global impact, as it is both theoretically feasible and has the possibility of not being prohibitively costly. Stratospheric aerosol scattering involves putting particles, usually sulfate aerosols, into the atmosphere. The sulfuric acid clouds that form from the sulfate aerosols would reflect the sun’s rays, causing a cooling effect. This same effect can be seen when large volcanic eruptions release large amounts of sulfur dioxide into the atmosphere that oxidizes to sulfuric acid clouds. SRM technology is unique to many other geoengineering technologies as it can use volcanoes as natural, if moderately inaccurate, models to help assess the feasibility and potential side effects of sulfate aerosols.
The aerosols could be distributed by aeroplane or military artillery, but would not be a permanent solution. The sulfate gases would need to be continuously replaced as they fell out of the atmosphere, and if neglected would cause the Earth to continue on its warming trend.
Aside from the issues around scaling and application of the technology, the ethical concerns broached by researchers of SRMs are considerable. David Keith, a researcher of solar geoengineering at Harvard, spoke to ***the New York Times about the concerns in his area of research: the lack of confidence in the effectiveness of the techniques, the possibility of disastrous consequences, and the ethics around international manipulation of the global climate.
In a paper on SRMs, Alan Robock, a climatologist at Rutgers University, wrote: “Geoengineering does not now appear to be a panacea, and research in geoengineering should be in addition to strong efforts toward mitigation, and not a substitute. In fact, geoengineering may soon prove to be so unattractive that research results will strengthen the push toward mitigation.”
Geoengineering has historically been a taboo area of research. Although research in the field has been ongoing for well over 50 years, discussions around bioengineering were pushed into the public sphere only recently by an editorial essay written by Paul J. Crutzen, a Nobel Prize-winning atmospheric chemist.
Crutzeh wrote: “Finally, I repeat: the very best would be if emissions of the greenhouse gases could be reduced so much that the stratospheric sulfur release experiment would not need to take place. Currently, this looks like a pious wish.”
Geoengineering’s ideas seem seductively straightforward, and there is concern that policy makers may grab onto the hope of a perceived easy technological solution instead of initiating change through the development of green technologies and reducing carbon emissions.
The world may not have the luxury of these concerns, however. In 2015 a binding agreement between nearly every country in the world was signed in Paris; 187 countries as of November 2019 have ratified the Paris Climate Accord, including Canada.
The overall goal set in this agreement is frequently cited in media discussions of climate change: we have agreed to limit global warming to no more than 2°C above pre-industrial levels, with a goal of 1.5°C, by reducing our greenhouse gas emissions. This may not seem like a considerable amount, but it is important to remember that this is a global average. During the last ice age, the average global temperature was only 4°C colder than pre-industrial levels, so it is easy to imagine the significant changes to our planet that a number even half that can bring.
Sadly there is no need for the imagination. Although there has been action, few of the countries who signed the Paris Agreement five years ago have made commitments that would meet the temperature limitation goals.
According to the Global Carbon Project, there was an overall increase in GHG emissions of 0.6 per cent between 2018 and 2019. At the current rate, warming is projected to reach 3°C, and global emissions have continued to rise.
“The oceans are acidifying, the soil is degrading, crops are becoming less nutritious, desertification is spreading, the ice caps are melting, and we’re destroying biodiversity,” Ovais Sarmad, UN Climate Change deputy executive secretary, said in a recent speech.
The countries that are moving toward green energy are moving too slowly, and too many are not moving at all. Geoengineering should not be seen as the solution, but as a supplement to the ongoing mitigation efforts, and mitigation efforts need to be dramatically increased.
However, as concerns around climate change grow and geoengineering research becomes more viable, we need to not just discuss the ethics around acting to intentionally alter nature, but the ethics around not acting and whether geoengineering technology can help in our fight against climate change.
Illustration: Mikaela Collins/The Cascade
