Australia could face “mega-droughts” lasting more than 20 years in the future, a new study has warned.
The latest study paints a worrying picture of future droughts in Australia, which researchers say could be far worse than anything experienced in the recent past.
Mega-droughts are extremely severe, prolonged and widespread drought events that can last for decades or even centuries.
Researchers from the Australian National University (ANU) and the Center of Excellence for Climate Extremes say their findings reflect the situation since the Industrial Revolution, before accounting for human-induced impacts on climate.
Co-lead author Dr. Georgy Falster from the ANU Research School of Earth Sciences said that if a mega-drought were to occur in Australia today, the consequences would be exacerbated by the climate crisis because any drought would occur with warmer weather conditions already in place.
“Adding naturally occurring mega-droughts that can last 20 years on top of climate change means that in the future Australia could face droughts worse than anything experienced in the recent past,” Dr. Falster said.
We need to consider and prepare for the possibility that one of these multi-decade mega-droughts could occur in the near future.
The study focused extensively on the Murray-Darling Basin, Australia’s largest agricultural region, to assess the potential severity of future droughts. The study found that the basin, which is already vulnerable to water scarcity, could face droughts that occur every 150 to 1,000 years and last for centuries.
The researchers used multiple climate models to simulate droughts over the past millennia (from 850 to 2000) and determine how they might change in the future.
This research includes estimates of the duration and level of droughts in Australia.
“One of the striking findings of our study is that droughts in Australia are likely to last much longer than the droughts we have experienced recently. Droughts lasting 20 years or more could become something we expect to happen,” the scientists said.
Researchers say mega-droughts are part of natural variations in Australia’s climate. But what’s now worrying, Dr. Falster said, is that “we’re adding human-induced climate change into the mix, and that’s probably increasing the likelihood of the next mega-drought.”
Co-author Nerilie Abram, who like the researchers in the study is a lecturer at ANU, said:
One thing we can do to reduce the potential severity and duration of future droughts is to rapidly reduce greenhouse gas emissions. For example, this could be a rapid transition to renewable energy sources.
