Mankind is constantly blowing climate-damaging CO2 into the atmosphere – and thus heating up the planet. There is a broad consensus that emissions must be reduced to contain the climate crisis.
But can the harmful greenhouse gas also be effectively removed from the atmosphere? A recent report confirms that the international community has a lot of catching up to do.
“CO2 removals are a necessity. They will not fall out of the sky, we have to take care of them,” said Jan Minx of the Mercator Research Institute on Global Commons and Climate Change (MCC), one of the study authors, in an online briefing to journalists .
First report of its kind
Together with other climate researchers from Germany, Great Britain and the USA, Minx published a scientific inventory of the extent to which methods of removing climate-damaging CO2 from the atmosphere are already being used and how they would have to be used in order to achieve international climate goals. According to the team, the report is the first comprehensive of its kind and is intended to be the first in a series.
The main conclusion: Although the removal of CO2 from the atmosphere is essential for compliance with the Paris goals, states hardly or not at all provide for the further development of novel forms in their climate protection plans. Although CO2 is already being removed from the atmosphere today, it is almost exclusively through conventional methods such as afforestation.
Various CO2 removal methods
The scientists distinguish between novel methods such as direct CO2 removal from the air with subsequent storage (DACCS) or carbon capture and storage (BECCS). Roughly speaking, energy is obtained from plants and the resulting CO2 is then stored. Since the plants keep growing back, they can use this to remove CO2 from the atmosphere. According to the authors of the report, nothing would work without these innovative methods.
According to the report, the new methods currently bind just 0.002 gigatonnes (billion tons) of CO2 per year. In order to achieve the climate goals – averaged over various scenarios – 30 times as much would have to be removed by 2030, and by the middle of the century even 1300 times as much.
“We’re really still at the beginning, we’re almost at zero,” says expert Minx. For comparison: According to estimates, global CO2 emissions in 2022 were 40.6 gigatonnes.
Reducing emissions is still necessary
The scientists warn against seeing the removal of CO2 from the atmosphere as an alternative to ambitious climate protection. A rapid and far-reaching reduction in emissions is urgently needed.
“It’s not about either/or. We need both,” said co-author Oliver Geden from the Science and Politics Foundation. In all realistic scenarios that are available for achieving the Paris climate goals, the removal of CO2 from the atmosphere is planned. However, there is a big gap between the goal and the current status of what the countries are implementing or specifically planning.
In Paris, the world community agreed to keep global warming well below two degrees compared to pre-industrial levels, but if possible to stop it at 1.5 degrees. This is to avoid crossing dangerous tipping points with irreversible consequences and averting the most catastrophic consequences of climate change. However, the measures planned so far by the states are far from ambitious enough for this.
According to the report, no country is presenting a plan with its national climate goals for how new extraction methods are to be scaled up by 2030. Even with the long-term climate goals up to 2050, this has hardly been planned so far.
Residual emissions must be offset
At the same time, the researchers point out that any country or company that has set itself a net-zero emissions target – commonly referred to as carbon neutrality – has already priced in the removal of CO2. Because there will always be residual emissions that have to be offset.
Politics and science must therefore clarify which methods they want to use to remove CO2, to what extent these are used and who should pay for them. “If you don’t have an answer to this, you can’t really take your net zero goal seriously,” says Geden.
The coming years are crucial
According to the authors, the coming years will be crucial for the further development of novel methods for CO2 removal and for creating the political framework for their scaling. Only if this happens is it realistic that they will be used on a large scale as needed in the second half of the century.
Whether this happens also depends on the public perception of the topic, emphasized Christine Merk from the Institute for the World Economy at the University of Kiel, who reviewed the report.
Another decisive factor is who is discussing the topic and how, for example in politics. “So far, this has been discussed so little that it is hardly known to the public and is not viewed in a differentiated manner.” Approval for conventional, natural methods such as afforestation tends to be higher than for less well-known extraction methods. But the conventional measures have their limits: Expert Geden noted that rising temperatures could also affect trees, making them more vulnerable as reliable CO2 stores.
