The topic of climate change has been a frequent subject of discussion in the news media for the past several years, but lately the subject seems to be discussed with more frequency and urgency. And with good reason — the U.N. has concluded that limiting the overall amount of global warming to 1.5 degrees Celsius is necessary to prevent the worst effects of climate change on civilization, and scientists warn that doing so will require massive, widespread changes to the way we harness and use energy. In response to this urgency, several democratic candidates participated in a climate-themed town hall hosted by CNN, during which they laid out their various plans for handling the crisis, with most focusing on placing a tax on carbon emissions and investing in renewable energy. But notably absent from most of the public conversation surrounding climate change is the subject of geoengineering — in other words, using technology to deliberately interfere in the earth’s climate system in order to curtail the worst effects of climate change.
The reasons for the absence of this approach in the public dialogue are easy to imagine. For one, the implications of the term “geoengineering” bring to mind the science-fiction movies, TV shows, and novels of the mid-twentieth centuries, making the concept seem little more than a far-fetched fantasy. And the approach of using technology to remove carbon from the atmosphere before eliminating carbon emissions seems like a counter-intuitive mismanagement of resources. But given the scale of the problem facing our planet, and the dire consequences of inaction, many scientists argue that all approaches, including geoengineering, need to be given serious consideration in our civilization’s quest to protect ourselves from disaster.
Even the most ardent supporters of geoengineering efforts admit that the process won’t be easy. For one, many of the technologies necessary to capture carbon, or otherwise mitigate the effects of climate change, haven’t been invented yet. Also, even the most modest estimates for the costs of developing and deploying these technologies are astronomical, and there doesn’t exist the same market incentive to fund geoengineering efforts as there does for oil and gas companies to remain the dominant providers of global energy. But scientists rightly point out that the rapidly accelerating pace of scientific progress means that technologies unimaginable just a few decades ago are today widespread, and whatever it will cost to ensure an inhabitable planet for generations to come pales in comparison to allowing the warming climate to destroy the environment.
A number of different geoengineering projects have been proposed, ranging from the mundane to the exotic. One proposal, which has already been implemented in some areas, is to continue to burn fossil fuels for energy but to capture, utilize, and store carbon emissions instead of allowing them to pollute the atmosphere. This approach has the benefit of being applicable to already-existing means of power production, as fossil fuels currently account for over 90% of the world’s energy sources, as well as relying on technologies that already exist. However, capturing carbon emissions introduces inefficiencies into the energy production pipeline, and requires the installation and maintenance of specialized equipment at power plants, both of which impose costs that energy producers may be reluctant to pay. While the International Energy Agency considers carbon capture “a critical tool in the climate energy toolbox,” it is clear that other solutions are also necessary for a successful global geoengineering effort.
Another idea is to spray particles into the atmosphere that would reflect sunlight, thus reducing the greenhouse effect. This approach carries with it a number of concerns. For one, given the extreme complexity of the global climate system, it’s difficult to predict what unintended side effects could arise, particularly when it comes to changes in weather events for individual locations. Spraying reflective particles into the air could result in a lessening of overall global temperatures, but the unexpected changes to weather patterns in various countries that could arise may lead to disaster in other ways. Other proposed methods of reducing the greenhouse gas effect include increasing the reflectivity of surfaces on the earth or of the ocean, or even deploying mirrors or shades in space to prevent sunlight from reaching the earth’s atmosphere.
A third approach, carbon dioxide removal, aims to address climate change by scrubbing greenhouse gases out of the atmosphere. Also called negative emissions, this approach relies upon deploying new technologies which currently exist only in theory. Another way of removing carbon dioxide from the atmosphere is, quite simply, planting trees. While this approach seems the most practical, difficulties in executing afforestation or reforestation efforts include securing the rights to large swaths of land for the purpose of creating forests, and the cost of planting millions of trees across a wide area. As one of the effects of carbon dioxide emissions is the acidification of the oceans, another idea in geoengineering is to fertilize the ocean with iron or other chemicals to revitalize marine life, including bacteria and algae.
Climate change is an extremely complex and multifaceted issue, with elements that affect nearly all aspects of civilized life. As such, the approach to dealing with climate change is similarly complex, and reducing carbon emissions by switching to renewable energy should only be part of the solution. While plenty of work still needs to be done in developing and refining geoengineering projects, global citizens should remain open-minded in our responses to a warming planet to ensure that the crisis is addressed effectively.