The dystopian images of wildfires ravaging vast swathes of woodland around the globe belie a rare positive signal for the Earth’s climate — the amount of carbon dioxide emitted by burning forests actually fell in 2020.
That’s the conclusion of atmospheric scientists at the European Union’s Copernicus Climate Change Service. They use satellites to take pictures and collect air-quality data from hotspots around the world. Despite this year’s widely-shared images of the raging infernos, which disrupted economies from Australia to the US west coast to Siberia, the amount of land that went up in flames declined.
“While areas such as the Arctic Circle and western United States suffered wildfires of unprecedented intensity and emissions, 2020 was one of the lowest years for active fires at the global scale,” the Copernicus Atmosphere Monitoring Service reported. “This has led to a further decline in emissions, following a continuing trend of the past 17 years. “
To reach their conclusions, the scientists used satellites to measure the amount of heat that was radiated by fire hotspots around the globe. Near-real-time data and observations are used to calculate the amount of carbon emitted globally. About 10% less carbon dioxide, some 1,690 million metric tons, was discharged from burning forest fires in 2020 compared to the year before.
“While 2020 has certainly been a devastating year for wildfires in the most badly-affected hotspots, emissions across the world have been lower due to better fire management and mitigation measures,” said Mark Parrington, a senior scientist and wildfire expert at Copernicus.
Fires emitted an estimated 79.6 million metric tons of carbon dioxide in California this year through 14 September. Wildfire emissions in 2020 for the whole of the US reached 200 million metric tons, almost a third higher than all of 2019.
Blazes in the Arctic Circle, which experienced the worst-ever fire season this year, emitted 244 million metric tons of carbon dioxide during the first six months of the year.
“Wildfires in the worse affected areas were of record intensity as a result of warmer, drier conditions,” Parrington said. “This resulted in increased pollutants being carried thousands of miles, affecting air quality for millions of people.”