Researchers from the Scottish Universities Environmental Research Centre (SUERC) found a new way to determine the outcome of stored carbon dioxide (CO2) emissions. The increasing levels of global warming continue to pose risks such as massive wildfires and extensive droughts.

CO2 byproduct from coal burning and other energy generation processes add to the accumulative global warming rate and its effects. Carbon capture and storage (CCS) refers to the process of storing CO2 in abandoned gas and oil fields. Deep aquifers - water-bearing rocks found underground - were also identified as an alternative storage unit.

Trapping CO2 emissions underground will help prevent the greenhouse gas from getting to the atmosphere. Scientists claim that a general usage of CCS in the next few years will help in the reduction of CO2 emission levels and, ultimately, slow down global warming.

The research team used gas samples from the wells at the Cranfield enhanced oil recovery field in Mississippi in southern America. They focused on samples taken in 2009 and 2012. A 'fingerprinting' process enables the scientists to study 'unique signatures' from noble gasses such as neon, helium and argon to monitor potential CO2 movement.

The paper's co-author, Professor Finlay Stuart from SUERC University of Glasgow, expressed that the research proved how the noble gases in the injected CO2 can be used as fingerprints. The finding is first of its kind. By looking at the gases' unique signatures, scientists can then monitor the CO2 and how it was disposed.

Stuart explained the huge potentials of CCS as a CO2 mitigation method. However, before CCS can develop into a widespread CO2 storage process, further research is needed to determine the effectivity of stowing the greenhouse gas underground. Noble gases such as neon, helium and argon are chemically inactive. Its interaction with water and rocks will have no effect in its activity. This level of inactivity can help identify the physical procedures that altered CO2 and determine its fate.

The study's co-author Dr. Stuart Gilfillan from the University of Edinburgh, expressed that the findings is beneficial to large-scale fingerprints in future CCS projects.

"This study now shows that these fingerprints can be used to track the movement and fate of injected CO₂ over much shorter periods relevant to CCS," said Gilfillan.

The research was funded by the Engineering and Physical Sciences Research Council in the United Kingdom. Researchers published their paper in the International Journal of Greenhouse Gas Control on Sep. 29, 2015. The University of Glasgow released the study findings online on Oct. 5, 2015.

Photo: Rebecca Humann