Last year's devastating wildfires in the Amazon, Australia, Indonesia, and the Arctic Circle brought the environmental and economic impacts of climate change to the forefront of global discussion. These massive fires, some the size of a small country, destroyed primary forests and vulnerable wildlife, releasing billions of tons of greenhouse gases into the atmosphere, potentially accelerating global warming and triggering more fires. While carbon dioxide emissions from wildfires had declined in recent years, they increased again in 2019. Compared to previous years, the total carbon emissions from wildfires in 2019 were not particularly high. A Bloomberg report, based on data from the Global Fire Emissions Database (GFED), indicated that fire-related carbon emissions increased by 26% last year, reaching 7.8 billion tons, the highest level since 2002. However, overall, fire-related carbon emissions have been declining since the beginning of this century. While fire-related carbon emissions have been decreasing, total carbon emissions from human activities have grown even faster. Last year, fires accounted for one-fifth of the 36.8 billion tons of carbon released from burning fossil fuels, compared to one-quarter at the beginning of this century. Thick smoke from Australian bushfires spreads across Sydney. Photo credit: Nick-D (CC BY-SA 4.0) The location of the fires warrants attention. Is global warming causing a new trend in bushfires? Mark Parrington, a senior scientist at the Copernicus Climate Change Service, the EU's Earth Watch agency, pointed out in a Bloomberg report that carbon emissions from fires in 2019 were higher than in 2018 and 2017, "but still not far from the average. It is noteworthy that fires are starting to occur or increase in places where they were rare in the past." Overall, scientists believe that global warming will lead to an increase in bushfires. The biggest question now is whether last year's peak was a one-off event or the beginning of a new trend. In Australia, sparse grasslands, grasslands, and woodlands burn every year. However, last year's bushfires were unprecedentedly severe, especially in the temperate forests of the southeast, which normally do not ignite; the damage far exceeded normal levels. Researchers at the University of Frieze Amsterdam say that about half of Australia's carbon emissions this fire season came from the southeast. Rebecca Buchholz, a scientist at the National Center for Atmospheric Research in Boulder, Colorado, says that normally, fire carbon emissions are reabsorbed when the grass grows back a few years later. But this year, this cycle "may be pushed into an imbalance." Fires also occur regularly in the Arctic Circle. However, warming and reduced rainfall are making these fires more severe, more frequent, and more difficult to extinguish. What's special about the 2019 fires isn't the total number or emissions, but the location and intensity. Scientists have found that fires in some parts of Siberia and Alaska have burned longer than ever before. Wildfires in Indonesia and South American countries are often related to agriculture, burning not only forests but also peat. The Amazon rainforest, which spans several South American countries including Brazil, Bolivia, and Peru, sometimes has seasonal wildfires linked to agricultural activities. Although South American countries experienced more fires last year than in 2018, carbon emissions from these fires in 2019 were less than half the levels seen in 2004, 2005, 2007, and 2010. Indonesia's situation was unique, with fires becoming particularly intense in September, midway through the traditional fire season. Copernicus pointed out that this indicated many fires were deliberately started to clear land for agricultural conversion, especially in the paper and palm oil industries. What particularly worries scientists is that Indonesia is burning not only forests but also peat. Peat can burn at extremely low temperatures, making fires difficult to extinguish and almost undetectable in satellite imagery, thus hindering accurate calculations of carbon dioxide emissions. Worse still, peat fires release carbon stored underground for tens of thousands of years. While people and governments worldwide are aware of the urgency of climate change, greenhouse gas emissions from human activities such as transportation and industry remain at historically high levels. On January 8th, Copernicus announced that 2019 was the second hottest year on record, 0.1°F cooler than 2016. Scientists say this makes favorable fire-prone conditions—high temperatures, strong winds, and low humidity—more frequent. "We predicted this before," Parrington said. "Based on our research, if the Arctic becomes hotter and drier, the fires could be larger than previously observed." Source: Bloomberg report (February 10, 2020), Measuring the Carbon-Dioxide Cost of Last Year’s Worldwide Wildfires
