Wildfires more than double Australia’s annual carbon emissions

Record-breaking fires that have swept Australia have so far released the equivalent of the country's greenhouse-gas emissions from fossil-fuel use for an entire year, new research shows.

Australian bushfires likely contributed 900 million metric tons of carbon emissions, according to early estimates from scientists behind the Global Fire Emissions Database. In the 12 months prior to June 2019, Australia’s annual carbon emissions stood at 532 million metric tons.

The fires in Australia have decimated an area the size of England, with experts estimating that as many as 1 billion animals have been killed. At least 28 people have died and 3,000 homes have been destroyed in the country's worst-ever fire season. Fires typically burn between September and March, which is spring and summer months in the southern hemisphere. The economic consequences are expected to be long-lasting, with analysts expecting the gross domestic product to drop as much as 1.6% this year.

Measuring the emissions caused by wildfires comes with a large amount of uncertainty. The actual figure could fall between 650 million metric tons and 1.2 billion metric tons of carbon dioxide. Even on the lower bound, the 2019 fire emissions are likely to be the largest in the country’s history dating back to 1997, when satellites began monitoring fire emissions.

Australia is not alone in seeing its climate impact change dramatically by a disaster. In 2017, Chile suffered its worst wildfire season ever and produced emissions from the burning equivalent to 90% of the country’s annual greenhouse-gas output, according to Universidad de Chile’s Center for Climate and Resilience.

Fires have long been a part of Australian landscapes, where savannas, grasslands and open woodlands burn each year. Typically, it takes only a few years for the carbon released in such fires to be reabsorbed as grass and plants regrow, according to Rebecca Buchholz, a scientist at the U.S. National Center for Atmospheric Research. “But that may be being pushed out of balance.”

One of the factors that makes this an unprecedented fire season is the affected area across the southeast, which is made up of temperate forests that grow back much more slowly. About half the carbon emissions in this fire season have come from this region, said Guido van der Werf, a scientist at Vrije Universiteit Amsterdam. “Those emissions may be reabsorbed or may be not,” he said. “It depends on when the next fire arrives.”

While Australia's greenhouse-gas pollution makes up just 1% of the world's total, the country ranks second when it comes to per-capita emissions. Australia emitted 16.2 metric tons of carbon dioxide per person in 2016, just below Saudi Arabia (16.3 metric tons) and slightly more than the United States (15 metric tons).