Turning Back The Planet’s Clock

By Hatim Husainy, Sustainability
Photo: Dmitry Makeev, CC BY-SA 4.0

Climate Change is an extremely complicated problem.

The Earth is an extremely delicate system—it has many layers and each of them interact with the others in ways we are still not completely sure about. This means that, when there is an imbalance, even a small one, it creates a huge change in the planet’s weather, temperature, and biological systems.

The best example of this phenomenon is climate change. Carbon dioxide, or CO2, even at today’s elevated levels, makes up about .04% of the Earth’s atmosphere. (NASAa 2024)

This is a 50 percent increase from pre-industrial levels, and it has a huge impact on the Earth system.  

This is not the only way we observe “small” changes having huge implications. We have accidentally been changing cloud formation over the sea for decades because of the sulfur we’ve been putting in fuels. Without sulfur, the fuels in ships now burn much cleaner, but with fewer clouds, the ocean is actually heating faster. Importantly, this truly doesn’t consider the emissions saved with clean-burning fuels, which still might make this change worth it even with the loss of cloud cover. (Harvey et al. 2024)

It is tempting to think of climate change as a problem that is mostly on the political and economic level. And while it may be true that the dynamics of humans have reached our hand to the heavens and put many lives at risk. Not just human lives, but many of the species of plants and animals that rely on a steady, predictable climate are now either at risk of extinction or will be soon. There is no time to make the wide-ranging political and economic realignment necessary to preserve the biosphere that exists today before it is too late. 

And so, we must consider radical action. What changed once can be changed again. To understand what type of action might be needed, it’s worth returning to the engine driving the crisis: the greenhouse effect. In short,  the Earth warms because gases like CO2 trap the heat energy that we get from the Sun, so when there’s an increase in CO2 concentration in the atmosphere, the planet gets hotter. (NASAb 2024)

Current climate “interventions” focus on reducing the amount of CO2 we are putting into the atmosphere. What these approaches tend to overlook is that even if we dropped to zero new emissions overnight, the acceleration of global warming would drop to zero but its velocity would remain. In other words, the amount of CO2 still in the atmosphere will keep the Earth heating long enough to cause biosphere-level collapse. The only way to find the time to develop technologies that can accelerate the process of getting CO2 back to preindustrial levels is to address the other part of the equation: decreasing the heat that Earth takes in from the Sun directly.

If we can alter the start of the equation by limiting the amount of energy that enters the Earth’s atmosphere, we can cool it down. This idea is described by scientists as solar geoengineering. Essentially, the particular mechanism is to create more clouds in the upper atmosphere so more sunlight is reflected. This could be accomplished by introducing more particles into the atmosphere—some scientists suggest sea salt for ease of access, while others propose sulfur dioxide because that is what has been proven to lower atmospheric temperatures when volcanoes throw large amounts of it into the atmosphere.

In comparison to making the hugely expensive transition from fossil fuels to renewable resources, geoengineering is incredibly cheap, not just in terms of real dollars, but also human labour-hours and mineral resources. Climate change is a challenge that will take time and money to solve: we must research carbon-capture farming, crops like hemp, kelp, and algae, and retool the entire energy apparatus of the US. In comparison to the cost of these new energy infrastructures and other research and development, geoengineering is relatively cheap. For an estimated 2 billion dollars a year, we buy valuable time to make these changes. (Harvard 2018) Even the research and development would be relatively inexpensive, because it is less creating an entirely new scientific process and more “an exercise in the application of existing tools from aerosol science, atmospheric science, climate research, and applied aerospace engineering”. (Keith 2017)

Of course, such a valuable and far-reaching stopgap cannot be deployed focusing only on scientific and financial viability. We must also consider governance: who would be consulted on what the resting temperature of the globe should be? There are also important effects to consider when we are ready to stop—or if we are forced to. 

The big question of governance is this: how do we get people to agree on what the earth’s temperature should be? Inherent to geoengineering is the ability to lower the Earth’s temperature; how far should we lower it? Some governments would massively benefit from an Earth warmer than preindustrial levels, much of the Siberian tundra may defrost at a sustained higher temperature. On the other token, cooling the Earth to cooler than pre-industrial levels would make desert reclamation easier in the Sahara or Mongolian desert (Davies 2025). Grant Davies argues that this is possible to agree on, as a global community, only under two conditions. First—countries need to gather in a process they see as fair, and arrive at a conclusion together—maybe agreeing on a temperature corridor that would be acceptable. Then, the countries that lose out in this arrangement would be compensated in order to maintain their buy-in. Ideally, this would be made easier by the already widespread process of carbon recognition that would need to simultaneously occur to make good use of the time we are buying. A “corridor” that keeps us within a tenth of a degree of preindustrial levels would do a lot of good. It would reverse somewhere between 150 and 400 years of global temperature rise in a matter of decades. This could be great—icebergs should cease to melt and perhaps even begin to grow again, ocean acidification would slow and coral reefs would have a chance to stabilize and recover, and total ecological collapse could potentially be avoided. 

The other big worry that lies right between issues of science and governance is termination shock. If for some reason the geoengineering program were to suddenly grind to a halt, it would be a big problem. The rapid cooling we had carefully engineered would quickly become reckless warming as the Earth returns to a degree and a half hotter than pre-industrial levels. Termination shock is an issue we can avoid—maintaining true global buy-in would be a very important element, for there would be relatively few parties looking to sabotage a hypothetical geoengineering program. Additionally, implementing geoengineering as a temporary solution and not our long-term strategy would make us less dependent on it and enable creating a timeline to slowly roll the program back once we are at a net-negative energy infrastructure.

In addition to termination shock, there are other scientific barriers to be considered. The increased cloud formation might slow photosynthesis or induce new extreme weather events. Additionally, direct tampering with the Earth’s delicate systems of weather might destabilize critical forces like monsoon winds of atmospheric currents, which could create unprecedented droughts, floods, or endanger agricultural yields (Lazard 2025). The biggest scientific problem is the data gap. We have not run small or medium scale experiments; much of the current literature relies on natural experiments (like volcanic eruptions or the sulfur fuel discussed earlier) but that is relatively small scale in relation to what a global cooling effort would look like.

There are many other problems that climate scientists have raised with geoengineering, in both theory and practice. Some of these are argued by Mike Hulme in his book “Can Science Fix Climate Change?” (London School Of Economics 2014). Hulme argues that climate change is an important opportunity to reconsider how we view humanity’s place in the world, rather than simply determining a new science fix in order to not change our lifestyles (Hulme 2014). His arguments are less focused on the political and economic forces that create and exacerbate climate change  more on the philosophical opportunity to reconsider the way we see secularism in our society and the postmodern “consensus.” He argues that climate change has resulted in a huge decentralization of thought—that, “Instead of the end of history, what we are witnessing is a flowering of the irrepressible diversity of human beliefs, ideologies and scepticisms” (Hulme 2014). That it is a moment for humans to reevaluate their views of their relationship with the natural world and the idea of nature, and reconsider how we live.

Much remains to be seen on the question of geoengineering. There are still big questions in science, the governance is still being built, and the societal question of what happens afterward remains unanswered (Woodwall Research Center 2023).  Geoengineering (changing the atmosphere on the molecular level) is a big change to propose. There are big questions about knock-on effects. But we are already doing geoengineering. We have already manipulated the atmosphere on the molecular level, and we are seeing the knock-on effects of an atmosphere with more CO2 than it can handle. We live on a rapidly warming planet not because of human technology but in spite of it. We have renewable energy that is scalable and all the tools we need to build a carbon-neutral society. The time is running out for us to put our technology into practice before we are forced to consider more radical solutions. We wield an unthinkable amount of power over nature—that gives us a responsibility to protect it.

References

Davies, G. (2025). Regulating geoengineering. Climate Technology and Law in the Anthropocene, 186–208. https://doi.org/10.2307/jj.18323828.13

Harvey, C., Harvey, C., & News, E. (2024, August 14). Cleaned up shipping emissions have revealed additional global warming. Scientific American. https://www.scientificamerican.com/article/cleaned-up-shipping-emissions-have-revealed-additional-global-warming/

Hulme, M. (2014). Climate change and virtue: An apologetic. Humanities, 3(3), 299–312. https://doi.org/10.3390/h3030299

Keith, D. W. (2017). Toward a Responsible Solar Geoengineering Research Program. Issues in Science and Technology, 33(3), 71–77. https://doi.org/https://www.jstor.org/stable/44577362

London School Of Economics. (2014, November 5). Book review: Can science fix climate change? by Mike Hulme – LSE review of books. LSE Review of Books – the latest social science books reviewed by academics and experts. https://blogs.lse.ac.uk/lsereviewofbooks/2014/08/27/book-review-can-science-fix-climate-change-by-mike-hulme/

NASA. (2024a, October 22). The atmosphere: Getting a handle on carbon dioxide – NASA science. NASA. https://science.nasa.gov/earth/climate-change/greenhouse-gases/the-atmosphere-getting-a-handle-on-carbon-dioxide/

NASA. (2024b, October 23). What is the greenhouse effect? – NASA science. NASA. https://science.nasa.gov/climate-change/faq/what-is-the-greenhouse-effect/

Olivia Lazard. (2025). Geoengineering: Assessing risks in the era of planetary security. Carnegie Endowment for International Peace.

School of Engineering, H. (2018, November 28). Calculating solar geoengineering’s technical costs. Home Page. https://seas.harvard.edu/news/2018/11/calculating-solar-geoengineerings-technical-costs

Woodwall Research Center. (2023). (rep.). Solar Geoengineering Research & Governance. Falmoth, MA.  https://www.jstor.org/stable/resrep55078