Article Excerpt: Australia’s summers are getting longer and winters have become shorter as a result of global heating, according to a new report from the Australia Institute.
The discussion paper, to be released on Monday, said that trend was “highly likely” to continue and would bring with it longer and hotter bushfire seasons, more heatwaves, while agricultural crops will be damaged, livestock will suffer and entire ecosystems will be placed at risk.
“If it feels like Australian summers are getting longer and hotter, that is probably because they are,” the report said. “The summers many Australians grew up with no longer exist.”
They found that between 1999 and 2018 Australia experienced summer temperatures for a full 31 days longer, compared to a benchmark between 1950 and 1969, while winter temperatures lasted 23 fewer days over the same comparative periods.
Over the past two decades, summer was on average a month longer than it was in the mid-20th century. The report said temperatures that “marked the start of summer now come around two weeks earlier”, and “temperatures that marked the end of summer now come around two weeks later”.
Last month, the Bureau of Meteorology confirmed 2019 was Australia’s hottest year on record, although the Australia Institute report was unable to include 2019 data in its analysis.
The researchers also narrowed in on temperatures over the past five years, measured against that same 1950-1969 benchmark, and found that summers were now on average close to 50% longer. “These most recent summers were twice as long as the most recent winters,” the report added.
Although they say that “caution is needed extrapolating to the future from past observations, especially over short time frames”, the researchers said it is “highly likely over the medium and longer them that summers will continue to get longer and hotter”.
“These trends are likely to continue indefinitely unless greenhouse gas emissions are decisively reduced, ultimately to net-zero,” the report said.