Can we geoengineer the Arctic? Should we?

As the impacts of climate change become more widely recognized, people have started to look for ways to lessen or mitigate climate change impacts. There are two main ways to counter climate change in the near term: 

1. Stop emitting greenhouse gases through international climate negotiations as well as bottom-up efforts to curb emissions

2. Actively cool the planet through geoengineering or “climate intervention”, a deliberate modification of Earth’s climate to reduce the worst outcomes of greenhouse gas-driven climate change. 

Geoengineering has long been a taboo topic amongst scientists and in politics because it’s similar to treating the symptoms of a disease rather than its root cause. Also, humans have a track record of creating new problems when trying to fix existing ones; for example, introducing one invasive species to combat another. On the other hand, one can argue that climate change is an urgent matter that requires multiple creative approaches.

Types of geoengineering

A number of proposed methods to cool the Arctic and slow the melting of its ice are being debated and discussed by researchers and governments around the world. The major challenge facing any proposal is the sheer scale of the Arctic. Existing proposals would be extremely difficult, if not impossible, to scale to the level required to reverse sea ice decline. Here are a few of the most discussed ideas:

Stratospheric Aerosol Injection (SAI) 

SAI involves reflecting part of the incoming solar radiation back to space like a sun umbrella. This could be achieved by spraying aerosols, tiny particles like those that make up a cloud from a wildfire, into the stratosphere (above where commercial airplanes fly), where they reflect sunlight. 

Arguments for SAI

The science is fairly well understood: The primary SRM idea is based on a well-known natural analog: explosive volcanic eruptions inject sulfur dioxide into the stratosphere, creating aerosols. These aerosols reflect solar radiation, leading to a measurable global cooling effect that lasts a bit more than a year — the time it takes for the aerosols to fall back out of the stratosphere. In other words, we understand a good portion of the relevant physics and chemistry from studying past volcanic eruptions. 

Costs may be feasible: The amount of sulfur dioxide we would need to inject into the stratosphere to combat the warming from greenhouse gases is not huge compared to how much humans already emit into the lower part of the atmosphere through industrial activities. It would be a significant effort to get the sulfur dioxide into the stratosphere, but costs might be smaller than the estimated damages from increasing extreme weather events.

Arguments against SAI

We don’t fully understand the risks: Although we understand much about the anticipated impacts of SAI, we have never lived in a world with a perpetual volcanic eruption keeping global temperatures in check. Significant uncertainties remain. Scientists are running hypothetical scenarios of SAI with climate models on big supercomputers to better understand how our climate would change — not just in terms of global temperature, but also in terms of regional rainfall patterns and social and economic effects.

Are the changes brought about by SAI worse than the impacts from climate change? And for whom? The jury is still out and, therefore, deployment of SAI would currently be a big risk. So far, this research is mostly based on computer simulations, but humans will eventually want to test these ideas in the real world.

Termination shock: Perhaps most worrisome, what if SAI were terminated before we managed to curb greenhouse gas emissions? Called “termination shock,” this scenario would see global temperatures jump to whatever greenhouse gas concentration level we’ve reached within just a few years, a potentially extremely disruptive warming rate.

Governance: Who decides how much SAI to deploy? What is the optimal level and for whom? Given current world affairs, it is difficult to imagine that countries would easily agree on these important details. 

Sea ice thickening 

In a warming world, Arctic sea ice extent shrinks and the ice gets thinner. Thin sea ice, in turn, is more vulnerable to break up and melt during summer, accelerating its overall decline. One idea is therefore to artificially thicken sea ice whenever it forms by pumping ocean water onto the ice. The water will freeze and thicken the ice, helping it survive for longer, although it would not necessarily increase the ice extent. The pumps would be operated by energy from wind turbines.

Arguments for sea ice thickening

Footprint and flexibility: Pumping water onto sea ice is among the least intrusive geoengineering methods proposed, essentially amplifying the natural process of ice growth. It could also be deployed strategically in places of particular importance, such as where communities rely on stable sea ice for mobility. As sea ice forms in slightly different places every year, the pumps would have to be mobile.

Governance: Deployed at small scales, this approach could be governed by local authorities in coordination with federal agencies and governments, akin to a ski resort that makes its own snow. This could be more feasible than larger-scale interventions, which trigger more complicated governance issues.

Arguments against sea ice thickening

Scalability: For this method to have an Arctic-wide impact, millions of pumps would need to be installed, many of them on sea ice. Installing, maintaining, and removing such technology on dynamic sea ice is logistically challenging and costly.

Sea ice albedo management 

This idea tries to increase the “albedo”, or reflectivity, of sea ice by spreading hollow glass beads onto existing sea ice. The glass beads would help reflect back incoming sunlight, keeping the sea ice cool, so it can survive for longer.

Arguments for sea ice albedo management

Costs: If deployed relatively locally in regions of particular need for thicker sea ice, technological and financial hurdles would be relatively small. Scaling it Arctic-wide would be a much more difficult task.

Arguments against sea ice albedo management

Ecotoxicity: The effect of glass beads, in stable or dissolved form, on oceanic organisms is currently understudied, posing unknown risks.

Governance: Glass beads would be dispersed across territorial boundaries by wind, requiring intra-governmental agreement and coordination.

Arguments for geoengineering

A possible “quick fix”

Climate damages are increasing. The latest assessment report of the Intergovernmental Panel on Climate Change (IPCC) made very clear that we are in the process of fundamentally changing our climate through greenhouse gas warming. The risk for large-scale disruption of ecosystems increases with every additional tenth of a degree of warming. 

At the same time, reducing greenhouse gas emissions has proven challenging. While there has been progress towards more carbon-neutral energy production, it is not happening fast enough to prevent growing climate change impacts. 

Therefore, it makes sense to look for a “quick fix,” a temporary solution to stave off the worst effects of global warming while we work on reducing emissions to get the climate back into equilibrium.

Possible local benefits

Most global geoengineering ideas face substantial challenges in terms of scalability, costs, and governance. It might be more feasible to find local applications in places of critical need, for example in the context of communities reliant on local sea ice for transportation (frozen lakes, rivers, estuaries). However, those applications would not be able to reverse global or even Arctic-wide climate change impacts.

Arguments against geoengineering

Geoengineering doesn’t address other problems related to warming

Geoengineering is not a cure-all. It would mostly combat warming but would do nothing against other climate change issues such as ocean acidification, which is a result of increasing carbon dioxide being dissolved into the ocean. There is also evidence that certain ocean currents, which weaken under warming, would not bounce back to previous levels.

Delayed action on greenhouse gas emissions

There is concern that focusing on geoengineering would slow our momentum towards reducing greenhouse gas emissions. Psychologically, it’s like a patient experiencing relief after his symptoms, but not their cause, are being treated.

Costs, scalability, governance

Many of the proposed geoengineering methods currently appear very costly, are not easily scalable, and it would be difficult to decide who governs the deployment of the methods.

Unintended consequences

Deploying geoengineering methods, locally or globally, can have unintended consequences, in particular in fragile ecosystems such as the Arctic. For example, it is unclear whether deploying sea ice-thickening pumps in polar bear hunting or denning areas would not disturb the bears as much as it would help them.

Why does it matter?

We need to understand the risk vs. reward

Ever since one of the first proposals for climate intervention was published in the 1990s, the prevailing argument was that even researching this topic was an ethically wrong distraction from the real problem.  

A counterpoint is that in the 1980s computer model-based research revealed that the climate effects of a global nuclear war would be far worse than the bombs themselves, arguably supporting a lasting nuclear peace and serving as an example of the value of researching even some ethically questionable topics.

A recent paper takes a critical look at several proposed geoengineering ideas for the Arctic, including the ones discussed above, and concludes that all carry substantial environmental risk, are not scalable, or too costly. The authors also worry that investment into geoengineering research takes away funds and momentum from pursuing the ultimate goal of reducing greenhouse emissions. 

World governments are weighing in

With mounting climate damages and the increasing willingness of billionaires to privately fund research into geoengineering, it has now become a topic that cannot be ignored. In fact, recent years have seen reports on geoengineering from the National Academy of Sciences as well as funding calls from federal science agencies for studying the potential impacts from geoengineering. Given the importance of geoengineering for world politics, one can expect that many actors will want to weigh in and that the misinformation campaigns common to politics will affect this topic. 

Research needs to be transparent

It is vital that geoengineering research is conducted in the most transparent way possible, including at public universities, to provide society with the necessary information to discuss its pros and cons. Funding sources and conflicts of interest need to be disclosed, partnerships need to be vetted carefully, and scientific results need to be interpreted against the backdrop of ongoing climate change and the relative failure to address its root cause.

Polar Bears International’s position

While Polar Bears International is not opposed to responsible research on ways to creatively mitigate the threat of climate change, we share the widely voiced concerns about governance and unintended consequences from large-scale geoengineering experiments. The primary focus must be on reduction in greenhouse gas emissions, alongside working with communities on reducing human-bear conflict to ensure polar bears have a future in the Arctic. 

Dr. Flavio Lehner is the chief climate scientist at Polar Bears International and an assistant professor in Earth and Atmospheric Sciences at Cornell University.