(CN) — This year's catastrophic wildfire season in Canada has released a record amount of carbon emissions and pollutants into the atmosphere, amounting to about three times more than the last Canadian record, set in 2014, according to a new report.
Canada's wildfires emitted 410 megatons of carbon emissions, or about 27% of the 1,520 megatons of carbon discharged by wildfires so far this year around the world, according to Copernicus, the European Union's climate change service. In 2014, Canadian wildfires emitted 138 megatons of carbon.
Copernicus uses satellites to monitor the atmosphere and calculates emissions caused by wildfires through its atmospheric observations. Global wildfire carbon emissions have been tracked by satellites since 2002.
Huge amounts of carbon get into the atmosphere when wildfires rage, and in years like this the levels surpass the annual amount of carbon big industrial countries such as Germany release by burning fossil fuels. However, scientists say fire emissions only contribute a small amount to global warming because burnt areas remove carbon from the atmosphere as they grow back.
More than 900 wildfires continue to burn in Canada, though the worst of the season is over, according to Canadian news reports. The boreal wildfire season typically runs from May to October.
Since March, more than 6,267 fires have erupted across Canada, burning about 42.7 million acres of land, or more than 66,000 square miles, according to the Canadian Interagency Forest Fire Centre. That amounts to about 5% of Canada's forest area and more than double a previous record set in 1989.
Smoke from the fires choked numerous northern U.S. cities this summer with dangerously polluted air and reached parts of the Southeast in the United States. Plumes even drifted all the way to Europe, Copernicus said.
Copernicus said Canada's fires continue to give off carbon emissions, though the amount is leveling off and not increasing.
Mark Parrington, a Copernicus senior scientist, said global warming is behind a spike in wildfires around the planet in recent years.
“As temperatures keep increasing and dry conditions become more long term, the chances of experiencing devastating wildfires like those in Canada are increasing,” Parrington said in a statement.
Major wildfires broke out elsewhere in the Northern Hemisphere, including in the boreal regions of Russia, Maui, Hawaii, and around the Mediterranean. The worst fires in Europe spread in Greece between July and August with a massive wildfire in the northeast of the country scorching a record amount of land in the EU.
Although wildfires contribute to global warming, Parrington said they are a much smaller factor than the burning of fossil fuels. Mostly, this is because of the new growth in previously burnt areas, where vegetation removes carbon from the atmosphere.
"Generally, fire emissions are a small part of land-use change and are fairly insignificant compared to fossil fuel emissions globally," he said in a telephone interview Thursday.
But wildfires emit many harmful pollutants other than carbon, fouling the air and seeping into drinking water. Also, some areas may not grow back after severe wildfires, and that means there isn't new growth to suck carbon back out of the atmosphere, he added. Wildfires are contributing to climate change in more subtle ways, too, such as leaving layers of soot on top of Arctic sea ice and on Greenland's ice sheets, possibly accelerating ice melt, he said.
While massively destructive wildfires in North America, Australia, Europe, Russia and elsewhere have become an ominous development as the world's temperature rises, the amount of carbon emissions from wildfires each year has actually been decreasing for the past three decades, Parrington said.
The reason for the downward trend relates to farmers in tropical regions of Africa burning less and less land, he said.
"There are changes of practices," he said. "Fire is not being used in agriculture; they used fire to clear vegetation to plant crops, and vegetation would grow back in the wet season, and then they would burn again."
What is troubling, he said, is seeing Canada burn for so long. "What we don't typically see is five months of non-stop fires in Canada."
Courthouse News reporter Cain Burdeau is based in the European Union.Follow @https://twitter.com/cainburdeau
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