CLIMATE change could see less-reliable water supply from the Great Artesian Basin within 75 years, according to a new study.

Central and southern regions drawing water from the GAB face the greatest risks under future climate change, according to the study authors, Surat Basin expert Dr Ben Lyons and his University of Southern Queensland colleague Dr Mahdiyeh Razeghi.

South Australia and areas around Broken Hill in western NSW and Weipa at the tip of Cape York could face up to 30 percent reduction in rain by 2099, while places like Birdsville in far western Queensland could see warming by up to 4 degrees C – a 15-20pc increase.

Dr Mahdiyeh Razeghi

Dr Ben Lyons

The pair delivered their findings at a recent international rangeland conference in Adelaide, warning that the GAB – Australia’s most-critical freshwater resource – faces possible dewatering.

Set to a historical baseline of 1975–2005, their climate model simulations coupled 20 years of satellite data with climate projections to 2099, using both low- and high-emission scenarios.

Dr Razeghi said even low-emission scenarios showed a gradual increase in drought intensity, particularly in areas like Broken Hill and Weipa.

“Temperature increases exacerbate evapotranspiration, which could increase by 10-15,” she said.

Dr Razeghi said it was crucial to start adopting adaptive water management strategies, such as managed aquifer recharge (MAR) and improved irrigation. MAR involves injecting water into aquifers for subsequent use or environmental benefit.

She explained that water levels in the GAB fluctuated.

“For example, from 2002 to 2022 positive anomalies are observed in the northern regions, such as Weipa, while negative anomalies dominated southern areas like Coober Pedy.”

Dr Lyons explained the science behind the findings.

“Recent advancements in remote sensing have greatly improved monitoring of drought conditions. Satellite data plots changes in the Earth’s gravity field, which is directly influenced by changes in water mass, giving more accurate insights than traditional ground-based methods such as streamflow measurements or groundwater monitoring,” he said.

He noted some of the positive possibilities arising from the study.

“We found that transitioning to low-emission pathways can reduce the risks of extreme droughts by approximately 10-20pc and support long-term resilience in the GAB.

“Also, integrating satellite-based monitoring into decision-making will enhance drought mitigation and water resource management, ensuring sustainable water use in the region under future climate change scenarios.”