Climate Models Point to Increasing Importance of Geoengineering in Years to Come

As rising sea levels present a challenge, scientists have found a way to combat this effect of climate change, which is caused by global warming. This phenomenon, known as global warming, refers to the rising temperature of the planet and is one of the biggest threats today. 

Long-term shifts in temperatures and weather patterns are a natural occurrence that has been going on for a long time. However, scientists assert that ever since the 1800s, the pace of this change has increased significantly, primarily due to human activities.

Global warming occurs when greenhouse gases such as carbon dioxide, nitrous oxide, and methane absorb sunlight and solar radiation. These pollutants then trap the heat, causing temperatures to rise. Scientists attribute this to fueling hotter heat waves, wildfires, more frequent droughts, more damaging hurricanes, heavier rainfall, and intensified weather patterns.

Yet another effect of global warming, as previously mentioned, is the rising sea levels caused by the melting of glaciers and Earth’s ice sheets. Predictions state the sea level rise from Greenland alone could reach about 10 cm by 2100. The future of the ice sheet and its long-term stability, however, hinge on the extent of summer warming it undergoes.

To mitigate the effects of climate change and protect the densely populated coastal lands from becoming uninhabitable, scientists propose several solutions, including geoengineering, which aims to alter aspects of the Earth’s natural systems—such as soils, oceans, and atmosphere—to counteract climate change.

Geoengineering encompasses large-scale, deliberate, man-made interventions, introducing the potential to manipulate the environment to avert the worst-case warming scenarios. There are primarily two types of geoengineering strategies: solar radiation management (SRM) and carbon dioxide removal (CDR).

SRM, or Solar Geoengineering, seeks to cool the planet by reflecting a small fraction of the sun’s energy back into space. Proposed methods include albedo enhancement, space reflectors, and stratospheric aerosols. 

Meanwhile, CDR, or carbon geoengineering, focuses on removing warming agents like CO2 from the atmosphere through techniques such as afforestation, biochar, ambient air capture, ocean fertilization, ocean alkalinity enhancement, and enhanced weathering.

Another technique, cloud seeding, aims to enhance winter snowfall and increase mountain snowpack, thereby addressing pollution and augmenting the natural water supply for surrounding communities. Numerous studies on cloud seeding have reported significant success.

Saving the Deteriorating Glaciers via Geoengineering

Given the potential of geoengineering, an international team of researchers from the University of Lapland, Finland, and the Institute of Low-Temperature Sciences, Hokkaido University, came together to utilize the geoengineering technique called stratospheric aerosol injection or SAI on ice sheet melting. 

In this method, aerosols are introduced artificially into the second layer of Earth’s atmosphere, i.e., stratosphere, by aircraft or high-altitude balloons. This creates a cooling effect by increasing albedo and global dimming.

Under the 2015 Paris Agreement, nations committed to reducing greenhouse gas emissions with the goal of cutting ice sheet losses to between one-third and one-half of their current levels. However, the study contends that inducing further cooling by injecting aerosols into the stratosphere at approximately one-fourth the rate of the Mt. Pinatubo eruption in the Philippines could reduce ice sheet loss by about 30% compared to the reductions achievable through the Paris Agreement’s emission targets. 

When Mount Pinatubo in the Philippines erupted, it injected about 15 million tonnes of sulfur dioxide into the stratosphere, causing a drop of 0.6 degrees Celsius in the average global temperature over the next 15 months.

Now, with SLA, scientists want to mimic that volcanic eruption. This aerosol geoengineering method preserves the size of both the smaller glaciers and seeps glaciers near their present sizes. 

On examining the effectiveness of using SAI in slowing the projected ice loss in Antarctica, a study from Nov. 2023 found that the region’s ice loss can be slowed by using SAI. However, the results depend on the location of the aerosol injection. Putting the particles between 30°N and 30°S, with the majority in the southern hemisphere, was shown to have the best potential to slow the Antarctic ice loss.

Now, researchers are trying this method in Greenland, where the likes of Jakobshavn, 79N, Zachariae Isstrøm, and Petermann glaciers are some of the fastest deteriorating glaciers in the world.

According to the study published in the Journal of Geophysical Research, the rise of the earth’s surface and sea level (SLR) due to dynamic losses from the ice sheets and surface melt can be potentially mitigated by cooling the ice sheet and oceans via solar geoengineering. 

To estimate the SLR contribution from the Greenland ice sheet, the team used two dynamic models driven by changes in surface mass balance (SMB). One of the models includes Representative Concentration Pathway (RCP) 4.5, which is a method to model the possible evolution of future climate adopted by the Intergovernmental Panel on Climate Change (IPCC). The other one is Geoengineering Model Intercomparison Project G4.

Over the 2020–2090 period, mass loss under G4 is found to be about 31%–38%. While calving losses vary, both models point to significant ice discharge losses, which are between 15% and 42%. Quantifying iceberg calving, which is the breaking of ice chunks from a glacier’s edge, continues to be a challenging task with respect to Greenland ice loss. 

In order to study the potential effects of SAI, researchers used the SICOPOLIS model (a 3D/thermodynamic model that simulates the evolution of large ice sheets and ice caps). The team simulated the changes in the Greenland Ice Sheet for the period 1990–2090 under RCP8.5, RCP4.5, and GeoMIP G4 scenarios. 

The simulations showed that stratospheric aerosol injection of sulfur dioxide has “a clear protective effect” on the ice sheets of Greenland.

Under RCP8.5, the worst-case climate change scenario characterized by the highest emissions and continuous warming, the projected ice loss equates to a sea-level rise of approximately 90 mm. Transitioning to RCP4.5, a scenario that represents a mid-way path with emissions levels potentially attainable under current conditions, the expected ice loss would correspond to a sea-level increase of about 60.6 mm. Under GeoMIP G4, which involves RCP4.5 plus the injection of 5 million metric tons of sulfur dioxide per year between 2020–2070, ice loss would be limited to just a 37.6 mm rise in sea level. 

The results were found to be similar when all these scenarios were evaluated using the Elmer/Ice model, a different dedicated model for fast-changing ice sheets.

“While this study shows that SAI could contribute to the protection of the Greenland Ice Sheet, and hence, potentially, all other ice cover on Earth, geoengineering is a highly contentious topic.” 

– Professor Ralf Greve, who co-led the study along with Professor John C. Moore

He added:

“The biggest issue is that it addresses only the symptoms of global warming, not the root causes—and may even delay the changes required to address the causes. Furthermore, due to the immense complexity of the natural systems on Earth, it is impossible to predict exactly what positive and negative outcomes could result.”

Is Geoengineering the Future of Climate Solutions?

The science behind geoengineering is promising, but it is still largely unexplored. For instance, blocking the sun’s heat to combat this continued rise in global temperatures seems a pretty clear and effective way. However, such schemes could have other long-lasting effects on the climate.

It has been argued that the arbitrary use of techniques like SAI is not only incompatible with sustainable development but also antithetical to climate justice. Such issues could be a new source of geopolitical tension. Not to mention, implementing such measures has a varying impact on food production.

As one study noted, when opting for moderate climate intervention, those in the mid-latitudes, North America and Eurasia, are likely to see increased food productivity due to SAI. Meanwhile, large amounts of atmospheric sulfur spraying can lead to a surge in Central America, Mexico, the Caribbean, and the top half of South America, parts of the Middle East, most of Africa and India, all of Southeast Asia, and most of Australia.

It goes to show that cold regions may prefer no such interventions as they may benefit from warming due to climate change in contrast to more tropical countries, which may favor high levels of intervention for cooler temperatures in order to have more crops.

But this is not all. Back in 2020, MIT scientists found that solar geoengineering proposals could also weaken extratropical storm tracks. This translates to less powerful winter storms as well as stagnant conditions in summer. It further affects the circulation of ocean waters and, in turn, the stability of ice sheets. So, it doesn’t simply reverse climate change but carries a potential “to induce novel changes in climate.” 

This is why many believe geoengineering is a temporary solution to the climate crisis. However, over the past decade, many researchers have conducted studies to examine if geoengineering can really provide us with a serious alternative.

Such techniques are worth exploring due to the cut down of emissions happening at a really slow pace to make an immediate impact on climate change. Moreover, some techniques, such as light-reflecting methods, offer the benefits of reversibility, speed, and relative cost-effectiveness.

Most recently, David W. Keith, a professor of geophysical sciences and founding faculty director of the Climate Systems Engineering initiative at the University of Chicago, and Wake Smith, a lecturer at the Yale School of Environment and a research fellow at the Harvard Kennedy School, noted in an MIT piece that the deployment of geoengineering should be made at a small scale. 

When it comes to SAI, the authors suggest a group of countries start a subscale deployment in about five years to produce clear changes in the composition of the stratosphere. They wrote:

“A well-managed subscale deployment would benefit research by reducing important uncertainties about SAI.” 

While beginning with an outright comprehensive deployment is both unwise and implausible, a slower start will provide us with a gradual reversal of warming. This facilitates optimization and reduces the chances of any unexpected effects. 

The subscale deployment over a decade would demonstrate the storage and dispersion technologies for their large-scale deployment. It would assess monitoring capabilities and clarify how sulfate is carried around the stratosphere and how it interacts with the ozone layer. Overall, this will provide us with a better understanding of the scientific and technological barriers to large-scale deployment. David said:

“If we are correct that such subscale deployments are plausible, then policymakers may need to confront solar geoengineering—its promise and disruptive potential, and its profound challenges to global governance—earlier than is now widely assumed.”

For now, the focus for everyone remains on more research, as the Climate Overshoot Commission demonstrated by calling for the experimental geoengineering methods to be halted until they’ve been researched thoroughly. 

A UNESCO report from Nov. 2023 has also called for assessing the ethical, social, and cultural risks of such methods and called for a ban on the weaponization of them. It also urged countries to make agreements to avoid risks of unequal spatial distribution of effects.

Additionally, the report said that political or economic interests shouldn’t interfere with scientific research on geoengineering. It added:

“Sharing of scientific knowledge and research data is a global responsibility for anyone involved in climate research, including climate engineering, in order to ensure informed policymaking and public debate on climate change.” 

This constant barrage of criticisms towards geoengineering methods has been particularly rising since last year, which shows a growing discussion and debate about this new way of modifying the Earth’s climate.

In fact, a study from late last year says that exposure to climate change information predicts public support for the controversial climate policy measure. As per the study, exposure to information underlies support for research and deployment, which was stronger in the US.

As per the study, support for SAI has been found to be the highest in China and lowest in Canada and the United States, while Germany, Switzerland, and the UK were in between. Similarly, support for SAI was reported to be higher in the Global South than in the Global North. In the Global North, support was weaker in Japan and South Korea than in Australia, hinting at an East–West divide. 

The US government actually announced a Five-Year Plan in 2022 to study Solar Geoengineering to temporarily reduce the effects of global warming. This is a clear indication of geoengineering’s growing prominence in discussions on climate policy. And while geoengineering seems dangerous, it is certainly helping buy us more time to address climate change.

Companies Working to Combat Climate Change

Now, let’s take a look at a couple of names that are fighting climate change using innovative methods. 

#1. Climate AI

This company utilizes machine learning, climate data, climate models, and in-field satellite imagery for detailed insights into future weather patterns to help farmers make informed decisions and build the future of farming. The climate resilience tech aims to climate-proof supply chains and global economies. Climate.AI has been working with food and agriculture companies across the world. 

#2. Microsoft

This tech giant has committed to becoming carbon-negative by 2030, and in another two decades, it aims to offset all greenhouse gas emissions it has ever produced. 

In 2017, Microsoft launched AI for Earth to develop innovative solutions to manage Earth’s natural systems. It currently supports over 950 projects and has deployed over 20 solutions worldwide.

The company has a market cap of $3 trillion, with its shares (MSFT) trading at $406.60, up 7.83% YTD. The company posted a revenue (TTM) of $227.58 bln and has an EPS (TTM) of 11.06 and P/E (TTM) of 36.67. It pays a dividend yield of 0.74%.

Final Word

Geoengineering has many benefits in terms of climate mitigation, temperature reduction, agricultural productivity, and biodiversity preservation. And research shows that it can finally help us mitigate the effects of climate change and save the planet. 

However, it’s not without risks, and given its wide-ranging effects, this largely nascent field needs to be explored extensively. With more research, sufficient investment, and oversight, these innovative solutions could become a vital part of the controlled global mitigation effort in the coming years.

Click here to read about how to tackle atmospheric CO2 – should we opt for prevention or treatment?