Climate change has driven a significant increase in Australia’s forest fire activity over the past three decades, according to new research from the Commonwealth Scientific and Industrial Research Organisation (CSIRO).
Chief Research Scientist in the Climate Science Centre at CSIRO, Pep Canadell said the research also identified a lengthening of the fire season towards Autumn and Winter, along with an increase in fire activity in cooler and warmer regions, including alpine forests in Tasmania and tropical rainforests in Queensland.
Dr Canadell said the research was the first of its kind and combined analysis of previous forest fire sites with eight drivers of fire activity, such as climate; fuel accumulation; ignition; and management.
“While all eight drivers of fire activity played varying roles in influencing forest fires, climate was the overwhelming factor driving fire activity,” Dr Canadell said.
“The results also suggest the frequency of forest megafires are likely to continue under future projected climate change,” he said.
“Over the last 90 years, three of the four mega fire years occurred after the year 2000.”
Dr Canadell said a mega fire year was defined as the cumulative burned area of forest over one year of more than one million hectares.
The Chief Research Scientist said globally, fire activity was decreasing, however, the extent of forest fires in Australia was increasing.
“When comparing the first half (1988-2001) with the second half (2002-2018) of the record studied, the research showed that the average annual forest burned area in Australia increased 350 per cent, and 800 per cent when including 2019,” he said.
“Comparing the same time period, the research showed a five-fold increase in annual average burned area in winter and a three-fold increase in Autumn, with Spring and Summer seeing a 10-fold increase.”
Dr Canadell said fire frequency had increased rapidly in some areas and there were now regions in the southeast and south with fire intervals shorter than 20 years.
“This is significant because it means some types of vegetation won’t reach maturity and this could put ecosystems at risk,” he said.
Dr Canadell said understanding the trends would help to inform emergency management, health, infrastructure, natural resource management and conservation.
