Looming megadrought poses massive threat to Australia's food bowl

Food supply, mental health and the environment could be severely impacted by a 20-year drought.

Australia is facing fresh misery at the supermarket with a predicted 20-year ‘megadrought’ putting food prices at risk.

The phenomena, not seen since records began in 1910, would see lower crop yields resulting in surging grocery prices and farms going out of business. Wildlife would also be impacted by water shortages and localised extinctions could occur.

Megadroughts are part of the country’s natural weather cycle, but not enough time has passed since records began for one of these “worst-case scenario” droughts to be documented.

“One hundred years isn't long enough to fully understand the possible range of droughts that we could get… just because we haven't had one recently, it doesn't mean that we might not get one soon,” co-lead author Dr Georgy Falster told Yahoo News Australia of the research which focuses on the Murray-Darling Basin.

Left - empty shelves. Right - the back of a man looking at meat in a supermarket.
Supply chains could be impacted by a severe megadrought. Source: Getty (File)

Falster was part of an Australian National University (ANU) Research School of Earth Sciences investigation into the range of droughts that could impact the country over a longer period. They found natural changes in rainfall have produced rare megadroughts that are decades or even centuries long, and Australia could soon experience one.

Megadrought fast facts

  • A megadrought could occur every 150 to 1000 years.

  • The Great Salt Lake in Utah is drying up due to a megadrought.

  • ANU reachers used several models to examine droughts between the year 850 to 2000.

Evidence megadroughts have occurred before

While there aren’t any megadroughts on record in Australia, there are signs in nature that they’ve occurred in recent years. A 2021 study that examined the rings on trees concluded megadroughts occurred in the southwest between 1828–1859 and 1755–1785.

The southwest of the United States has been experiencing a megadrought for the last 24 years, which experts believe is the driest the region has been in 1200 years.

Concerningly climate change appears to be a driver of rainfall declines, meaning megadroughts of the future could be worse than previously experienced. “What climate change does is worsen the severity and impacts of droughts, and it is also showing a tendency to drive longer droughts,” Falster said.

This prediction is in line with a 2022 warning from the Climate Council's Dr Tim Flannery who said the impact of global warming could cause more disruption to Australia's food supply lines than the Covid-19 pandemic.

Warning to prepare for megadrought

A megadrought would be far worse than anything the nation has experienced in living memory, including the Millennium Drought which stretched from 2001 to 2009. During that time farmers were unable to plant crops, and tourism nosedived in hard-hit regions like Tamworth in northeast NSW.

Falster hopes the ANU research will spur authorities to prepare to mitigate the problems it would cause by securing water supplies and ensuring mental health support services are in place. “Droughts put huge financial and emotional stress on people, particularly farmers, so it’s super important to get community support in place in advance of these big droughts occurring,” she said.

After releasing the new research, co-author Professor Nerilie Abram stressed the importance of reducing greenhouse gas emissions to help lessen the potential impact of a megadrought.

“It is likely that changes to drought intensity could still arise as climate change continues to worsen,” Professor Abram said. “One example of this is the 21st century ‘Tinderbox Drought’, which was only three years long but was exceptionally intense and set the conditions for the Black Summer bushfires. The Tinderbox Drought was likely made more severe by climate change.”

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