"Safely Storing Carbon Underground: New Research Reveals Limitations"

How much carbon can we safely store underground? Much less than previously thought

Drawing down carbon from the air and stashing it in underground rock formations has been framed as an essential way to slow and reverse global warming. But new research published Wednesday in the journal Nature finds there are far fewer suitable places to do this than previously thought.

After analyzing geologic formations across the United States, scientists have discovered that only a fraction of regions once considered suitable for carbon storage actually meet the criteria needed to ensure the carbon remains underground permanently. This revelation is a significant blow to efforts aimed at carbon sequestration, a key strategy in combating climate change.

The study's findings suggest that there are limited geological conditions that can safely host carbon storage projects. Factors such as rock permeability, porosity, and proximity to faults play a critical role in determining the effectiveness of underground carbon storage. Many previously identified sites are now deemed unsuitable, leaving policymakers and researchers with fewer options for scaling up carbon capture and storage initiatives.

The challenges of underground carbon storage

One of the main challenges associated with underground carbon storage is the risk of carbon leakage. If the stored carbon were to escape back into the atmosphere, it would undermine the very purpose of sequestration efforts. In addition, the potential for induced seismicity, or human-induced earthquakes, poses a significant risk in regions where carbon injection activities are taking place.

Furthermore, the long-term stability of stored carbon remains a concern. Changes in pressure and temperature underground can lead to the re-release of carbon dioxide, complicating efforts to maintain secure storage over time. These challenges highlight the need for thorough risk assessments and monitoring protocols to ensure the safety and effectiveness of carbon storage projects.

Implications for climate action

The limitations identified in the study have significant implications for global efforts to address climate change. Carbon capture and storage technologies have been heralded as a crucial tool in reducing greenhouse gas emissions and achieving carbon neutrality. However, the newfound constraints on underground storage capacity suggest that reliance on this method alone may not be sufficient to meet climate targets.

As countries around the world strive to decarbonize their economies and transition to renewable energy sources, the need for alternative carbon mitigation strategies becomes even more pressing. From reforestation and soil carbon sequestration to innovative technologies that capture carbon directly from the air, a diverse portfolio of solutions will be essential in addressing the complexities of climate change.

Conclusion

While the prospect of underground carbon storage offers a potentially valuable avenue for reducing atmospheric carbon levels, the latest research indicates that the capacity for such storage is more limited than previously believed. This underscores the importance of a multi-faceted approach to climate action, one that combines carbon capture and storage with other mitigation strategies to achieve meaningful and lasting results in the fight against climate change.