Recent research reveals that the Earth's underground capacity to store CO2 is significantly lower than previously estimated, decreasing from around 13 billion to just 1.6 billion tonnes.

A study published in Nature indicates that the global capacity for underground carbon storage is roughly ten times less than earlier projections, which greatly limits its potential as a climate mitigation tool.

This limited storage capacity constrains how much we can reduce global temperatures through carbon sequestration, underscoring the urgent need for drastic emission cuts.

The study suggests that this capacity could only effectively lower global temperatures by about 0.7°C, far below the 1.5°C target of the Paris Agreement, with projections showing the planet warming up to 3.1°C by the century's end.

Scientists agree that human emissions must decrease rapidly because underground storage cannot indefinitely accommodate the volume of CO2 produced by ongoing fossil fuel consumption.

Many geological formations previously deemed suitable for storage could pose risks such as leaks, earthquakes, or groundwater contamination, reducing the practical potential of underground CO2 storage.

The research emphasizes that relying solely on carbon storage is insufficient; it should be a supplementary measure mainly for sectors that are hard to decarbonize, like cement, aviation, and agriculture.

Experts warn that the high costs and limited capacity of geological storage make it a problematic primary solution, reinforcing the need for immediate emission reductions.

While some scientists believe advances in engineering could address issues like induced earthquakes and water contamination, the overall capacity remains finite and cannot replace the need for cleaner energy.

Current practices such as CO2 injection in oil and gas extraction face limitations, making emission reduction at the source a more sustainable strategy.

Although alternative rocks like basalt could store more CO2, the study's focus on sedimentary formations likely underestimates the true potential, which remains limited.

The article warns against using geological storage as an excuse to continue polluting, emphasizing the importance of transitioning to cleaner energy sources.

Financial and political barriers, including reduced climate funding in the US, further hinder the deployment of effective carbon storage and emission reduction strategies.