Read time: 3 mins
Based on Potential for historically unprecedented Australian droughts from natural variability and climate change, published March 2024
Droughts are a naturally occurring feature of Australia’s climate. But evidence suggests that our future worst droughts could be much longer than we’ve seen since 1900. With droughts also likely to become more severe due to climate change, Australia must prepare a water policy that can handle these so-called ‘megadroughts’.
Read time: 3 mins
Based on Potential for historically unprecedented Australian droughts from natural variability and climate change, published March 2024
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In 1150-year-long climate model simulations, ANU researchers found that Australia’s longest natural droughts can last more than 20 years – much longer than those observed in the 20th century.
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The evidence suggests that such ‘megadroughts’ are a natural feature of the Australian environment.
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If a megadrought happened now, it would combine with higher temperatures due to climate change, and massively disrupt Australian society. Water management authorities should plan for longer, more intense droughts than Australian governments have dealt with before.
Living in Australia means dealing with drought. But lessons from new analysis of 1150-year simulations by ANU researchers suggest governments need to prepare for longer and more severe droughts than ever before.
The researchers used climate models that reliably match known data observed in the environment.
Having confirmed the accuracy of the models, the researchers then analysed simulations of Australia’s pre-industrial environment. This allowed them to build up a previously unseen picture of the climate from the previous millennium.
The simulations showed that long droughts have a long history.
The longest droughts observed in the 20th century are much shorter than the longest droughts of the pre-industrial past millennium, according to the models. These simulations showed the Murray-Darling Basin may have experienced droughts lasting up to 34 years, during the past millennium.
If a ‘megadrought’ like this happened now, it would be highly disruptive to Australian society.
Authorities should consider this possibility when making long-term decisions about water management across Australia, and especially in the Murray-Darling Basin.
“Living in Australia means dealing with drought. But new evidence from ANU shows that governments must prepare much longer and more severe droughts than they’ve dealt with before.”
