Australia is experiencing longer fire seasons and more frequent extreme heat, plus more intense rainfall, scientists say.

Last year produced one of the biggest bushfire seasons in terms of area burnt, due to increased fuel loads, according to the latest State of the Climate report, prepared every two years by CSIRO and the Bureau of Meteorology.  

“Across large parts of Australia, there has been an increase in extreme fire weather and in the length of the fire season,” the report says. “There has been a shift towards drier conditions across the south, with more frequent years of below average rainfall. In contrast, northern Australia has been wetter than average over the last 30 years.”  

The risk of coastal inundation and damage to infrastructure and communities is increasing with rising sea levels, and extreme heat has caused more deaths than any other natural hazard. It also affects infrastructure and ecosystems. 

The scientists say there is a shift toward drier conditions between April and October across the southwest and southeast, and reduced rainfall in the southwest “now seems to be a permanent feature of the climate”.  

The nation “must plan for and adapt to the changing nature of climate risk now for future generations”, they say. 

Australia’s climate has warmed by 1.51 degrees since 1910, while sea surface temperatures are up 1.08 degrees on average. Eight of the nine warmest years on record have occurred since 2013, and 2019 was Australia’s warmest year, followed by fewer heat extremes during an extended La Nina phase. 

The mean global sea level is up 22cm since 1900, increasing the risk of inundation and damage to coastal infrastructure and communities. 

Australia is projected to have more extremely hot days and fewer extremely cool ones over coming decades, and bureau climate services manager Karl Braganza says droughts this century have been “significantly hotter” than in the past. 

“Lower rainfall in the cooler months is leading to lower average streamflow in those regions, which can impact soil moisture and water storage levels and increase the risk of drought,” he said. 

Heavy rainfall events are becoming more intense, he says, with levels up 10% or more in some regions. 

Changes in the weather and climate are coming at an increasing pace, the report says, and the past decade has brought record-breaking extremes, contributing to natural disasters that are “exacerbated by anthropogenic (human-caused) climate change, including ‘compound events’, where multiple hazards and/or drivers occur together, which intensifies their impacts. These changes have a growing effect on the lives and livelihoods of all Australians.” 

The severity of impacts on Australians and the environment will depend on the speed at which global greenhouse gas emissions can be reduced, the experts say. 

See the report here. 

For in-depth analysis, features and opinion, read the latest Insurance News magazine