Climate threatsGeoengineering, other technologies won’t solve climate woes

The countries of the world still need to cut their carbon dioxide emissions to reach the Paris Agreement’s climate targets. Relying on tree planting and alternative technological solutions such as geoengineering will not make enough of a difference.

“We can’t rely on geoengineering to meet the goals of the Paris Agreement,” says Helene Muri, a researcher from NTNU’s Industrial Ecology Program. She was also one of the lead authors of a recent article in Nature Communications that looked at different climate geoengineering projects in the context of limiting global warming.

The average temperature on Earth is rising. The UN Intergovernmental Panel on Climate Change (IPCC) has recommended limiting this warming to less than 2 degrees Celsius, and better yet to less than 1.5 degrees. These targets were set in the 2015 Paris Agreement, which was ratified by nearly all nations.

Various geoengineering options are among the solutions being considered. They involve intervening directly in the Earth’s climate system to prevent temperatures from rising as much as would otherwise happen due to the increasing amount of greenhouse gases in the atmosphere. Geoengineering comprises reducing atmospheric CO₂ levels, or reducing the effect of the Sun.

Untested, uncertain, and risky
Can we remove greenhouse gases from the atmosphere with the help of technology or capture more CO₂ by planting millions of trees? Can we reflect more of the Sun’s radiation by injecting particles into the atmosphere?

“Several techniques could help to limit climate change. But they’re still untested, uncertain and risky technologies that present a lot of ethical and practical feasibility problems,” say Muri and her colleagues.

In short, we just don’t know enough about these technologies and the consequences of putting them to use, the researchers say.