Climate Engineering Offers Potential to Slow Antarctic Ice Loss

Injecting aeacutes into the stratosphere could reduce Antarctic ice melt and the risk of sea-level rise, according to research from Indiana University.

The Ross Ice Shelf at the Bay of Whales

A research team from Indiana University (IU) closely examined the potential effects of geoengineering on this continent, which is essential for maintaining climate balance in the face of the rapid melting of ice in West Antarctica. Their findings, published in the Journal of Geophysical Research: Atmospheres, shed light on the possibilities of reducing the risks of catastrophic sea-level rise by employing various climate manipulation methods.

Paul Goddard, a research assistant at the IU College of Arts and Sciences, raises a crucial point: even if the ambitious goal of limiting global warming to 1.5 degrees Celsius above pre-industrial levels were achieved, a significant rise in sea levels remains inevitable. Therefore, his study proposes climate engineering as a solution to buy time in the face of imminent climate changes and to avoid or delay climate “tipping points,” such as the collapse of the West Antarctic ice sheet.

The study’s co-authors include experts from various renowned institutions, such as Ben Kravitz, associate professor at IU; Douglas MacMartin and Daniele Visioni from Cornell University; Ewa Bednarz from the National Oceanic and Atmospheric Administration; and Walker Lee from the National Center for Atmospheric Research.

Geoengineering: A Controversial Solution to Mitigate the Climate Crisis

Climate engineering aims to selectively interfere with the Earth’s climate system. Among the studied methods, Stratospheric Aerosol Injection (SAI) stands out. This technique involves releasing sulfates or other reflective particles into the stratosphere to reflect solar radiation into space, mimicking the cooling effect of a major volcanic eruption.

The adoption of this method has even reached the level of the White House, which recently released a report examining the feasibility of a research program on SAI and improving the brightness of marine clouds.

Geoengineering: A Controversial Solution to Mitigate the Climate Crisis
The researchers compared the net ice accumulation in Antarctica for various scenarios of stratospheric aerosol injection (SAI) as well as a scenario of moderate emissions without SAI, correlating them with observed historical levels between 1990 and 2009. Blue areas represent a net gain in ice accumulation, while red areas indicate a net loss. The small points denote regions where no significant change is anticipated. The comparison period for SAI scenarios and the moderate emissions scenario extends from 2050 to 2069. Image: University of Indiana.

In the face of record temperatures, with ten of the hottest years recorded in the past fourteen years, including 2023, poised to surpass 2016 as the warmest year ever recorded, the study results sound an alarm. Advanced computer simulations have shown that different scenarios of stratospheric aerosol injection could be effective in slowing Antarctic ice loss.

Computer Modeling and Aerosol Injection Strategies

For this research, scientists utilized the powerful IU Carbonate computer to model various SAI strategies. “Where you release the aerosols matters a lot and can affect the climate differently,” explains Goddard in a statement. The results are conclusive: a strategic release of aerosols across multiple latitudes, with a higher concentration in the Southern Hemisphere, can significantly contribute to preserving continental ice by limiting the warming of ocean waters around Antarctic ice shelves.

Researchers modeled eleven different scenarios by deploying aerosols at various latitudes. The three most promising scenarios aimed at injection at different latitudes target temperature goals of 1.5, 1, and 0.5 °C above pre-industrial levels. The simulations, spanning from 2035 to 2070, also included, for reference, a scenario of moderate emissions without aerosol injection.

While these multi-latitude injection scenarios seemed beneficial for Antarctic ice preservation, it is evident that further studies are needed to precisely measure the reduction in melting rates, warns Goddard. Some single-latitude injection scenarios, in particular, led to faster melting of Antarctic ice due to a southward shift in dominant winds, pushing warm ocean waters toward ice shelves.

However, this method could pose significant risks, such as changes in regional precipitation patterns or the risk of “termination shock,” a rapid warming of the overall temperature to its original level if the intervention over long periods were suddenly suspended. Ben Kravitz also cautions that before considering the actual deployment of such techniques, the scientific community must address numerous gaps regarding the risks and regional effects related to solar radiation management, both for Antarctica and the rest of the planet.