Over long, geologic time scales, carbonic acid weathering is an important control on atmospheric CO2 levels and climate, but under the right conditions, weathering by sulfuric acid can release substantial CO2.

Ph.D. candidate Scott Zolkos and his supervisor, U of A biologist Suzanne Tank, found that these conditions are prevalent in the western Canadian Arctic.

“We found that rapidly thawing permafrost on the Peel Plateau in the Northwest Territories is greatly enhancing mineral weathering,” explained Zolkos, the lead author on the study. “Because weathering is largely driven by sulfuric acid in this region, intensifying permafrost thaw could be an additional source of CO2 to the atmosphere.”

The researchers worked with scientists from the Northwest Territories Geoscience Office to examine long-term records of river chemistry from the Peel River.

They found that weathering driven by sulfuric acid has intensified with regional permafrost thaw in recent decades, and likely increased the amount of CO2 released into the surrounding water and air.

Source: Thawing permafrost may release more CO2 than previously thought, study suggests