(Photo: Ice researchers say that some of the geoengineering concepts aimed at trying to slow polar ice melt are unaffordable and unrealistic. Credit: Sean Gallup/Getty Images)
A team of the world’s best ice and climate researchers studied a handful of recently publicized engineering concepts for protecting Earth’s polar ice caps and found that none of them are likely to work.
Their peer-reviewed research, published Tuesday, shows some of the untested ideas, such as dispersing particles in the atmosphere to dim sunlight or trying to refreeze ice sheets with pumped water, could have unintended and dangerous consequences.
The various speculative notions that have been floated, mainly via public relations efforts, include things such as spreading reflective particles over newly formed sea ice to promote its persistence and growth; building giant ocean-bottom sea walls or curtains to deflect warmer streams of water away from ice shelves; pumping water from the base of glaciers to the surface to refreeze it, and even intentionally polluting the upper atmosphere with sulfur-based or other reflective particles to dim sunlight.
Research shows the particle-based sunlight-dimming concept could shift rainfall patterns like seasonal monsoons critical for agriculture in some areas, and also intensify regional heat, precipitation and drought extremes. And the authors of the new paper wrote that some of the mechanical interventions to preserve ice would likely disrupt regional ocean ecosystems, including the marine food chain, from tiny krill to giant whales.
Lead author Martin Siegert, a glaciologist at the University of Exeter, said that to provide a comprehensive view of the challenges, the new paper included 40 authors with expertise in fields including oceanography, marine biology, glaciology and atmospheric science.
The paper counters a promotional geo-engineering narrative with science-based evidence showing the difficulties and unintended consequences of some of the aspirational ventures, he said. Most
geoengineering ideas are climate Band-Aids at best. They only address symptoms, he added, but don’t tackle the root cause of the problem—greenhouse gas emissions.
“I think it’s fair to say that the promotion of some of these ideas have not provided a sense of just how difficult it would be,” Siegert said. “So what you get is the maximizing of the potential of doing it and minimizing the challenge of it ever happening. It becomes a sort of distorted, one-sided proposition.”
To assess the feasibility of five specific concepts, he said they developed a set of questions that could also apply to geoengineering proposals in areas other than the poles. In nearly every case, they found that the costs and logistics are prohibitive, and that there’s no reason to think they would be effective in protecting ice or reducing the impacts of global warming in other ways.
The first question, he said, is whether the idea would even work in practice. Then, it’s important to think about risks, both the obvious ones and the unexpected side effects that might come with any intervention large enough to affect the climate. Money is an obvious factor, since these kinds of projects could cost tens or even hundreds of billions of dollars.
Size and timing matter, he continued. Any plan must be able to grow to a scale that truly helps within the next few decades to help reach global climate goals.
“We have to avoid giving people false hope by suggesting that climate change can be fixed without cutting carbon emissions, which is the only real solution,” he said, adding that special care is also needed in the polar regions because of their harsh conditions, logistical hurdles and delicate ecosystems. In places such as Antarctica, he added, international treaties meant to protect the environment would make large-scale interventions very difficult, if not impossible.
“It’s not that we wanted to do this study, but there is a very small minority that is really pushing this,” said co-author James Kirkham, chief science advisor for a group of more than 20 countries that first joined together at the 2022 COP27 U.N. climate talks in Egypt to focus more attention on the threat of melting ice and rising sea levels.
The following year at COP28 in Dubai, he noted that numerous events promoted concepts that are generally grouped under the term “geoengineering,” which refers to artificially and intentionally intervening with parts of the climate system. Many climate scientists were alarmed that some of the geoengineering ideas, no matter how far-fetched, seemed to be gaining traction with a few policymakers.
In some cases, the presentations were designed to look like they were sponsored by national pavilions, “even though at least the people we’ve talked to within these administrations don’t want anything to do with this at all,” Kirkham said. “The thing that really wound us up was that they were pitching these fringe ideas as if they had the backing of the entire research community.”
The assessment shows that “no current geoengineering idea passes an objective and comprehensive test regarding its use in the coming decades,” he said.
In an email, Kirkham wrote that most geoengineering ideas had long been “dismissed and ignored” by the mainstream climate science community. But in recent years, “there seems to have been a shift … with a lot more money flowing into these sorts of projects and the hiring of experienced and slick PR people to get these ideas out there into the media,” he said.
Ren Ecosystem