The Future of Water Supply: Climate Change Impacts on the Great Artesian Basin

CLIMATE CHANGE could threaten the reliability of water supply from the Great Artesian Basin (GAB) within the next 75 years, according to a comprehensive new study.

Regional Impacts Predicted

Experts Dr. Ben Lyons from the Surat Basin and Dr. Mahdiyeh Razeghi from the University of Southern Queensland have identified central and southern regions drawing water from the GAB as holding the highest risks associated with future climate changes.

Regions in South Australia, Broken Hill in western New South Wales, and Weipa at the tip of Cape York may encounter reductions in rainfall of up to 30 percent by 2099. Similarly, locations like Birdsville in far-west Queensland could experience an increase in temperatures of up to 4 degrees Celsius, which may translate to a 15-20% rise in evaporation rates.

Dr. Mahdiyeh Razeghi

Dr. Ben Lyons

Study Findings Presented at Rangeland Conference

The researchers shared their findings at an international rangeland conference in Adelaide, emphasizing that the GAB, Australia’s most important freshwater resource, could be at risk of dewatering.

Using climate model simulations based on a historical baseline from 1975 to 2005, the researchers combined 20 years of satellite data with projections up to 2099, considering both low and high-emission scenarios.

Drought Intensity on the Rise

Dr. Razeghi highlighted that even in low-emission scenarios, there is likely to be a gradual increase in drought intensity, particularly for regions like Broken Hill and Weipa.

“Temperature increases exacerbate evapotranspiration, potentially increasing by 10-15%,” she stated.

Adaptive Water Management Strategies Needed

Dr. Razeghi stressed the importance of implementing adaptive water management strategies such as Managed Aquifer Recharge (MAR) and improved irrigation techniques. MAR involves injecting water into aquifers for later use or for environmental benefits.

She clarified that the GAB exhibits fluctuations in water levels. For instance, from 2002 to 2022, positive anomalies were noted in northern regions like Weipa, while negative anomalies were prevalent in southern areas such as Coober Pedy.

Scientific Innovations in Monitoring

Dr. Lyons elaborated on how advancements in remote sensing technologies have significantly improved the monitoring of drought conditions. Satellite data enables the mapping of changes in the Earth’s gravity field, which is intrinsically tied to alterations in water mass, providing more accurate insights than conventional ground-based assessment methods.

Possibilities for the Future

Despite the challenges, Dr. Lyons found some encouraging prospects stemming from the study. “Transitioning to low-emission pathways can diminish the risks of extreme droughts by about 10-20%, promoting long-term resilience in the GAB,” he said.

Furthermore, the integration of satellite-based monitoring into decision-making processes could enhance drought mitigation efforts and streamline water resource management strategies, ensuring sustainable water use in the region amid future climate changes.