In the first report on the global situation of CO2 removal, the researchers call for the expansion of new technologies, since it has not yet been possible to significantly reduce greenhouse gas emissions.
Global warming can only be limited to a tolerable level if significantly more carbon dioxide is removed from the atmosphere. This is the conclusion of the authors of the first report on the global state of CO2 removal, published on Thursday. The more than two dozen scientists involved recommend a mixture of different options – from reforestation to technical filtration systems.
As it has not yet been possible to significantly reduce greenhouse gas emissions, the options for removing carbon dioxide (Carbon Dioxide Removal, abbreviated as CDR) must now be massively expanded, according to the Oxford University report. So far, the CDR has only played a marginal role; just two billion tonnes of CO2 are captured each year – with emissions of nearly 40 billion tonnes.
Currently, CDR is mainly practiced through conventional methods, such as the expansion of forests or wetlands that absorb CO2. Only a small part – about 0.1 percent – is linked to new technologies such as direct air capture or converting organic waste into biochar, according to the report.
Emissions expected to drop 45% by 2030
According to the Intergovernmental Panel on Climate Change, global warming must be limited to 1.5 degrees Celsius compared to the pre-industrial era in order to avoid catastrophic consequences. To achieve this goal, CO2 emissions must drop by around 45% by the end of the decade compared to 2020 levels and be reduced to zero by mid-century.
In 2022, however, emissions remained at very high levels, making CDR technologies even more important. But they just might be part of the solution, the researchers explain. “Regardless of whether we remove a little or a lot of carbon dioxide, we need to massively reduce greenhouse gas emissions,” Gregory Nemet, a professor at the University of Wisconsin-Madison and one of the authors of the inventory, told AFP.
According to the report, between 450 billion and 1.1 trillion tons of CO2 need to be removed by CDR by the end of the century. Conventional projects such as reforestation must therefore be doubled by 2050 to reach the 1.5 degree target. “Many policy makers don’t know and probably don’t want to know how much meeting the 1.5 degree target actually depends on removing carbon dioxide,” said co-author Oliver Geden of the AFP Science and Politics Foundation.
First certified CO2 capture and storage
One new CDR technology has received more attention and money than others: direct capture of carbon dioxide from the air combined with carbon storage (DACCS). Three-quarters of the US$200m (€185m) invested in new CDR capacity from 2020 to 2022 went to DACCS, with a large portion going to Swiss company Climeworks.
The company last week announced the world’s first certified carbon capture and storage on behalf of paying customers including Microsoft and software service provider Stripe. “These investments are based on the assumption that direct air capture can increase from around 10,000 tons today to a billion tons by 2050,” said Nemet.
Many carbon capture methods are currently being researched. For example, researchers are experimenting with ways to increase the ability of oceans and soils to hold carbon dioxide. The report’s authors advocate not just focusing on one technology, but a portfolio of solutions.