Uncovering the Climate Feedback Loop of Fool’s Gold in the Canadian Arctic: A Disturbing Discovery
A new study has found that the erosion of rocks like pyrite, also known as fool’s gold, in the Canadian Arctic could be driving a disturbing climate feedback loop. The weathering of sulfide minerals like pyrite releases carbon dioxide, and as more Arctic permafrost thaws due to warming temperatures, more rocks are exposed to the atmosphere and weathered, leading to increased CO2 emissions.
According to the study published in Science Advances, CO2 emissions from Canada’s Mackenzie River Basin could double by 2100, which is equivalent to half of the current annual emissions from the country’s aviation industry. The researchers, led by Professor Robert Hilton from the University of Oxford, found that the relationship between temperature and sulfide weathering appears to be exponential, meaning it accelerates as the region warms.
To investigate this climate feedback loop, the researchers collected data on sulfate concentrations and temperatures from 23 locations across the Mackenzie River Basin. They found that sulfide weathering increased by 45% between 1960 and 2020 as temperatures rose by 2.3 degrees Celsius. The chemical reactions were observed to occur at faster rates in mountain regions where rocks are broken open by frost cracking, while they were slower in lowland regions with a protective layer of peat.
While the exact extent of the problem remains unclear, the researchers are exploring ways to mitigate this process. Hilton mentioned that similar reactions are also occurring in other regions where rocks have been exposed by deforestation and land use change, such as the European Alps. Solutions like reforestation could help lower rock mineral reactions and CO2 release while building tree biomass and soil carbon stocks.
However, Hilton emphasized that while the weathering feedback loop is an important source of emissions in the Arctic, it is likely a smaller issue compared to the release of methane and carbon dioxide from thawing permafrost. He cautioned against being too alarmist about the findings and highlighted the need for further research to better understand and address this climate feedback loop.