Researchers reject geo-engineering as a climate-warming response

Researchers reject geo-engineering as a climate-warming response

Proposals to reduce climate warming in the polar regions through geo-engineering rather than carbon emission cutbacks would be dangerous and ineffective, according to an international team of scientists that includes two from the University of Alaska Fairbanks.

The 42-person team also said the geo-engineering proposals would distract from efforts to reach the 2015 Paris Agreement's goals of limiting global warming to well below 3.6 degrees Fahrenheit above pre-industrial levels.

Geo-engineering is defined as large-scale technological or environmental interventions to deliberately alter Earth's climate system to counteract global warming. Proponents have directed their ideas toward the Arctic and Antarctic because those regions are warming faster than elsewhere.

The team's findings were announced today in Frontiers of Science.

"The proposed geo-engineering methods are not more than a Band-Aid on a serious injury," said professor Regine Hock of the UAF Geophysical Institute and University of Oslo.

Hock is one of the scientists who initiated the research paper.

"They do not address the underlying causes of the climate crisis but may cause serious damage and are extremely costly," she said. "The only effective way to reduce further global warming is rapid decarbonization."

UAF professor Martin Truffer of the UAF Geophysical Institute and College of Natural Science and Mathematics is also a co-author of the paper. Both he and Hock are veteran glaciologists.

Martin Siegert of University of Exeter is the lead author. Other co-authors are from Norway, Belgium, Australia, Italy, Argentina, Sweden, France, Denmark, New Zealand, Austria and Canada. Several others are from the United States.

The concepts

The international team analyzed five ideas that have received attention in recent years:

• Increasing solar reflectivity by injecting aerosols such as sodium dioxide and titanium oxide into the atmosphere.

• Reducing sea-level rise by blocking warm, deep ocean currents from reaching key areas of Antarctica and Greenland to slow melting. This would be done by installing underwater barriers, so-called sea curtains.

• Increasing sea ice albedo and thickness by scattering hollow glass beads over first-year ice. Recent loss of sea ice has made Earth less reflective.

• Slowing glacier sliding and ice flow. Concepts include drilling holes to the glacial bed to pump out water, thereby increasing a glacier's drag on its bed; introducing coolants to the glacier bed; and placing obstacles in the glacier's path.

• Reducing atmospheric carbon dioxide by increasing ocean absorption of the gas. This would be done by fertilizing the ocean with iron to increase blooms of phytoplankton, which would draw in carbon dioxide.

"Any large-scale interventions in the Earth system carry a risk of large-scale unforeseen negative consequences," Hock said. "The Earth system is complex with many linkages between human, natural and biological systems."

Of the five concepts, Truffer says he is most concerned about solar radiation management.

"I find that really worrisome, because if you're going to start putting things into the stratosphere, you're going to affect climate everywhere," he said. "And there's a lot in the climate system that we simply do not understand."

Multiple concerns

The authors warn that geoengineering proposals give "a false hope that the effects of global warming can be avoided by means other than rapid, deep cuts to greenhouse gas emissions."

They write that the ideas proposed by engineers and other scientists are far too expensive. Also, the Arctic and Antarcticregions have complex environmental protection and governance systems that will likely reject polar geo-engineering.

And they write about "predatory delay, in which powerful actors" promote geo-engineering to justify continued emissions and preserve their own financial or political interests under a pretense of climate action.

"The 'bad actors' are not necessarily the scientists who are advocating geo-engineering research," Truffer said. "The people I know often acknowledge that this is very early in the research."

The research paper is a response to recent attention on the proposals and to proponents' use of phrases such as "climate repair" to suggest that the climate can be fixed without seriously reducing fossil fuel use.

"I was surprised by how quickly ideas that were long deemed undesirable, or even ridiculous, suddenly have gained traction," Hock said. "So it was time for us to take a stand and highlight the dangers and problems associated with large-scale geo-engineering."

ADDITIONAL CONTACTS: Regine Hock, [email protected]; Martin Truffer, [email protected]

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