Bushfires ravaging Australia have provided a foretaste of the kinds of conditions that could become normal unless the world moves rapidly to curb emissions of the greenhouse gases driving global warming, scientists have warned.
Although Australia’s government and parts of its media have attempted to downplay the role of man-made climate change in making the country more vulnerable to wildfires, a review of 57 scientific papers published since 2013 suggested clear links.
“We’re not going to reverse climate change on any conceivable timescale. So the conditions that are happening now, they won’t go away,” Richard Betts, Head of Climate Impacts Research at Britain’s Met Office Hadley Centre, who co-authored the review, told a news conference in London on Monday.
The review found that climate change had led to an increase in the frequency and severity of what scientists call “fire weather” - periods with a high fire risk due to some combination of hotter temperatures, low humidity, low rainfall and strong winds.
The effects had not only been observed in Australia, but from the western United States and Canada, to southern Europe, Scandinavia, the Amazon and Siberia, the review found.
Globally, fire weather seasons have lengthened across about 25% of the Earth’s vegetated surface, resulting in about a 20% increase in the mean length of the fire weather season, according to observational data.
Betts said Australia was particularly vulnerable to fires since its land area had warmed by more than the rise in average global temperature of about 1 degree Celsius since pre-industrial times.
The World Meteorological Organization says the global temperature increase could hit 3-5 C this century - more than three times limits agreed in the 2015 Paris Climate Agreement - if nothing is done to stop rising emissions.
“Temperature conditions in Australia are extreme at the moment but they are what we expect to happen on average in a world of three degrees of global warming,” Betts said. “It brings it home to you what climate change means.”
The review was carried out using https://sciencebrief.org, a new online research platform set up by Britain’s University of East Anglia and Tyndall Centre for Climate Change Research.
At least 28 people have been killed in the Australian fires that have destroyed 2,000 homes and razed 11.2 million hectares (27.7 million acres), nearly half the area of the United Kingdom.
After weeks of criticism over his handling of the crisis, Prime Minister Scott Morrison said on Sunday he would propose a high-powered inquiry into the disaster, including the impact of climate change.