A new study published in Geophysical Research Letters finds that about 76 percent of carbon emissions from Canada's record 2023 wildfires came from burning peat and soil, not trees. The research, led by McMaster University, used a machine learning model trained on NASA field data to estimate that the fires released roughly three times Canada's total annual reported greenhouse gas emissions. Peatlands alone accounted for about 33 percent of those emissions. The findings have major implications for climate policy. As climate change dries out peatlands, long term carbon stores that took millennia to accumulate can be released in a single fire season. The study's co author says better forest management alone cannot solve the problem, only steep cuts to global emissions can. This challenges recent political narratives blaming forest management for cross border smoke. Canada holds about one fifth of the world's soil organic carbon, making its northern peatlands a critical but increasingly vulnerable carbon sink. The study notes limitations in field data from Eastern Canada and calls for more ground measurements to improve estimates. For carbon markets and climate accounting, this research underscores the need to account for soil and peat emissions, not just aboveground biomass.
