Now That The Bushfires Are Out, It's Time To Discuss What Caused Them
For the first time in eight months, all the NSW fires are out. Now, a ground-breaking report has ruled climate change was a massive factor in the extreme fire conditions that devastated Australia this summer.
According to some official fire danger ratings, Australia's risk of having a fire season as bad as this years has increased by nine times, compared to 1900.
"Climate change contributed to the fires and extreme heat we lived through in southeastern Australia," Canberra climate scientist Dr Sophie Lewis said.
"(It) is now part of Australia’s landscape. Extreme heat is clearly influenced by human-caused climate change, which can influence fire conditions."
Lewis is part of the World Weather Attribution team of academics which, on Thursday, published a detailed report on extreme weather and the bushfire season.
In no uncertain terms, the study's authors -- including leading scientists from the University of Oxford, Columbia University and the Global Disaster Preparedness Center -- lay out evidence that climate change played a large role in Australia's months-long bushfire crisis.
More than 30 people died, and thousands of homes and buildings were destroyed, with more than 11 million hectares burnt.
The report found human-caused climate change increased the chances of Australia experiencing extreme fire weather by at least 30 per cent, and potentially up to 80 per cent.
It comes just days after the NSW Rural Fire Service said all active fires in the state had finally been extinguished -- the first time since July 2019.
"Facing fires like this, the question is not just 'is climate change having an effect on fire', but 'how is climate change affecting what I’ve just experienced'," one of the study's authors, Oxford University's Dr Friederike Otto said.
The study noted 2019 was Australia's warmest and driest year since observations began in the early 1900s.
Combined with the long-term Indian Ocean Dipole weather effect, this "led to weather conditions conducive to bushfires across the continent and so the annual bushfires were more widespread and intense and started earlier in the season than usual", the authors wrote.
The study found heatwave conditions of the severity of that experienced during Australia's 2019/20 summer would have been several degrees cooler, and far less likely, in the year 1900.
"We can therefore only conclude that anthropogenic climate change has made a hot week like the one in December 2019 more likely by at least a factor of two," the study noted, adding this may even be an underestimate.
"We find that the probability of extreme heat has increased by at least a factor of two."
Looking at official fire risk indices -- which analyses temperature, humidity and wind to calculate the risk of extreme fires -- the report found Australia's risk of having fires as extreme as this season has quadrupled since 1900.
On an index called the Monthly Severity Rating, which calculates how difficult a fire is to fight, the risk of a season as bad as 2019 in Australia has increased "by more than a factor of nine".
If global temperatures rise by two degrees celsius or more -- which is predicted by climate models, unless radical industrial and technological change is rapidly enacted -- the risks will become even higher, the experts have warned.
"There is evidence that Australian fire seasons have lengthened and become more intense, and extreme temperatures have played a role in this," Lewis said.
Climate change is now part of Australia’s landscape.
The report's authors have claimed current climate models may not accurately represent extreme heat or fire danger and stress the true picture may be even more startling than their findings indicate.
The study noted the damage of this season, but praised Australia's response.
"Australia is one of the most prepared countries in the world to manage bushfires and thus the impacts from this season’s bushfire outbreaks could have been dramatically worse if not for the systems in place," the report claimed.
"This underscores the urgent need to adapt to changing risks in all places, and especially the most vulnerable."
Dr Nikola Casule, Head of Research and Investigations at Greenpeace Australia Pacific, said the report should be a wake up call for governments worldwide, including Australia.
"Climate change is primarily driven by the burning of coal, oil and gas, so in order to keep Australian families safe from the worsening impacts of the climate crisis, the federal government must urgently commit Australia to 100 per cent renewable energy," he claimed.
"In the wake of one of the biggest climate disasters our country has ever seen, what Australian communities need now is strong leadership on phasing out coal, oil and gas: the primary cause of climate change."