23/08/2017

Climate Change Sets The World On Fire

Deutsche Welle

Southern Europe and British Columbia have been devastated by wildfires this summer. And they're not the only ones - it seems like much of the world is ablaze right now, and this could be the new normal.

There have been many wildfires aound the world this summer. Canada has seen the worst season for fires since records began, with 894,941 hectares burned, the British Columbia Wildfire Service has confirmed. Large areas of the Western United States have also been affected.
Meanwhile in Portugal, 2,000 people were recently cut off by flames and smoke encircling the town of Macao. And earlier this summer, 64 people were killed by a blaze in the country.
Like Canada, southern Europe has seen a record heatwave this year, creating hot, dry conditions that saw Italy, France, Croatia, Spain and Greece all swept by wildfires. As a result, Europe has reportedly seen three times the average number of wildfires this summer.
But it's not just Canada and southern Europe that have been affected. In Siberia, wildfire destroyed hundreds of homes, and around 700 hectares of Armenian forest have also been destroyed by fire. Earlier this year, Chile saw wildfires that were unparalleled in the country's history, according to the President.
Even Greenland, not known for its hot dry conditions, suffered an unprecedented blaze this summer.
Central Portugal has been one of the areas hardest hit by fires this summer
The big picture
"A lot of these things are happening locally, but people don't always connect them to climate change," said Kevin Trenberth, a scientist at the Climate Analysis Section of the National Center for Atmospheric Research in the US. "But there is a real climate change component to this and the risk is going up because of climate change."
With global temperatures rising, scientists say wildfires are likely to become increasingly frequent and widespread. "What's really happening is that there is extra heat available," Trenberth told DW. "That heat has to go somewhere and some of it goes into raising temperatures. But the first thing that happens is that it goes into drying - it dries out plants and increases the risk of wildfires."
The map above, compiling NASA satellite data on fires from the beginning of 2017 until mid-August makes it looks as if the whole world is on fire.
So is 2017 a record year of wildfires?
Wildfire rages in British Colombia, on July 8. It has now been confirmed the state's biggest in more than 50 years
Tough competition
It certainly looks like it's been a big year for fires in southern Europe and North America. But Martin Wooster, professor of earth observation science at King's College London, says other parts of the world have seen worse in recent years.
"For example, this year, fires across Southeast Asia are extremely unlikely to be anything like as severe as they were in 2015," he told DW.
Two years ago, drought caused by El Nino created lethal conditions for Indonesian forests and peatlands that were already degraded by draining and logging. The smoldering peat - ancient, decayed vegetable matter condensed into a carbon-heavy fuel - kept fires burning for months on end.
"This led to huge fires, far bigger than any seen in Europe, and some of the worst air pollution ever experienced," Wooster said.
NASA imagery shows a large wildfire burning in Sweden in early August
Longer fire seasons - longer recovery
But there does appear to be a distinct trend for fire seasons to be longer and more harsh. "In the western United States, the general perception is that there is no wildfire season any more, but that it's continuous all year round," Trenberth told DW.
In many parts of the world, wildfires are part of a natural cycle. Savannahs, for example, are maintained by fire. Some trees not only survive fires, but need them to release their seeds. Human intervention can disrupt these cycles, the scientific discipline of fire ecology has found. Putting out small fires can allow flammable debris to accumulate until a colossal fire starts that cannot be controlled.
But global warming is resulting in hotter, drier conditions that mean such infernos are becoming more common, even with careful forest management. And the changed climatic conditions can mean forests take far longer to recover. Meanwhile, fires are also starting in habitats in areas like the tropics that have no natural fire ecology.
A wildfire smolders near Nice in the south of France in July
Human fingerprints
Climate change isn't the only manmade factor. Fires can also be started by careless humans dropping cigarettes or letting campfires get out of control.
And in regions like the Amazon, where the annual fire season increased by 19 percent between 1979 and 2013, fire is deliberately used to clear forest to make way for agriculture. "Farmers light fires to clear an area and what happens in drought conditions is that these fires become wild because the vegetation is so dry, it gets out of control," Trenberth said.
And all this can have a feedback effect - more fires mean more carbon released into the atmosphere, which in turn drives climate change.
Wildfires rage through Southeast Europe: Too close for comfort
Smoke and flames rise from a fire in the Croatian village of Podstrana, near the Adriatic coastal town of Split, on July 18, 2017. In Croatia, the blazes have spread over several locations along the coast and onto the islands, engulfing pine forests and low shrubbery in extremely dry and windy weather.

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