The researchers tested carbon dioxide removal techniques

Annual carbon dioxide emissions continue to rise globally. Could removing carbon dioxide from the air be a climate solution? Researchers have examined the state of the technologies.

Carbon dioxide emissions continue to rise. Many countries have begun removing greenhouse gases from the atmosphere. But according to a major report, this is not enough to provide adequate climate protection. The most important thing in climate protection remains reducing carbon dioxide emissions, says the State of Carbon Dioxide Removal report team led by lead author Stephen Smith from the University of Oxford.

But by mid-century, CO2 extraction and storage must increase to seven to nine billion tons of carbon dioxide per year, the report says. Only then will it be possible to limit global warming to no more than 1.5 degrees, if possible, or at least well below 2 degrees, as agreed in Paris.

How successful are carbon dioxide extraction methods?

According to the report, if we do not want to exceed the potential CO2 budget of the 1.5 degree target, the CO2 must also be taken out of the atmosphere using different extraction methods – traditional and new – and deposited permanently on Earth for decades to thousands of years. Stored in oceans and geological formations. In the global report, scientists conducting research around the world in the field of carbon dioxide recovery present the new figures.

Reforestation of new forests

Currently, 2.2 gigatonnes of carbon dioxide are removed from the atmosphere each year worldwide. According to the researchers, this can be achieved almost exclusively through traditional carbon dioxide extraction methods. Above all, 99 percent comes from forests: reforestation of old forests and reforestation of new forests. Scientists expect annual absorption of carbon dioxide through these traditional extraction methods to increase slightly by mid-century.

By 2050, the amount of carbon dioxide removed will increase to seven to nine gigatonnes per year worldwide. According to the report, this can only be achieved if new CO2 extraction methods are further researched and expanded on an industrial scale. This involves, for example, capturing carbon dioxide directly from the air and subsequently storing it. However, these new methods are currently in laboratories or in pilot plants in individual countries. Currently, they represent only 0.1 percent of current CO2 extraction.

National Long term strategy

Germany has stipulated in its climate protection law that greenhouse gas neutrality – or, in short, the net zero goal – must be achieved by 2045. This means that although residual emissions – for example from cement production – cannot be avoided, they must be completely eliminated. From the atmosphere.

The coalition agreement stipulates the need for a “long-term negative emissions strategy.” “To do this, we in Germany have to be clear about the remaining emissions we want to bear.”, says Julia Pongratz, professor of physical geography and land use systems at Ludwig Maximilian University in Munich.. “It is currently assumed that in 2045 CO2 removal will be in the range of 60 to 130 million tons.

Recommendations for action To politics

Pongratz is a spokesperson for the CDRterra research program, in which about 100 scientists work together. Among other things, they studied the feasibility and risks of promising CO2 extraction operations on Earth and developed an evaluation framework.

From here, they developed recommendations for action to design the long-term national strategy. Its purpose is to determine which of the various carbon dioxide extraction operations on Earth should be launched and how to finance them.

The risks of removal procedures also need to be evaluated and weighed, Pongratz says: “If Germany succeeds in creating a reasonable set of carbon dioxide removal measures on the right scale, this means that we will in fact become among the leading countries in the European Union. The goals of the long-term national strategy must also be economics, politics and civil society.

Storage of industrially produced carbon dioxide

In Germany it was previously prohibited to store carbon dioxide in the soil. It has been allowed since last week. The Cabinet approves the law on carbon dioxide storage. Thus, Economy Minister Robert Habeck paved the way for storing artificially produced carbon dioxide underground. For the most part, the deep layers of rock in the upper North Sea are said to act as a reservoir.

The cement, chemical and steel industries are particularly affected. It is difficult for them to be able to produce their products with green electricity or hydrogen in the future. Therefore, they will continue to emit large amounts of carbon dioxide in the future.

Criticism of the report

The report itself points out a shortcoming in its numbers: it does not take into account the fact that some activities can be short-lived – for example due to unexpected disruptions or poor management.

Just maintaining carbon dioxide stores like forests will be a major challenge, the team wrote, pointing to the growing impacts of climate change such as changes in rainfall, wildfires, and bark beetle spread. This is likely to increase the gap needed to achieve the necessary CO2 removal.