A new study casts light on the vulnerability of global freshwater resources to climate change.

The research emphasises the dramatic changes in terrestrial water storage, with repercussions for extreme weather events like floods and droughts.

Dr Adeyeri Oluwafemi from the Australian Rivers Institute, the study's lead author, highlights the disruption of water's natural cycle. 

“Water from groundwater, rivers and rainfall is undergoing disruption in its natural cycle due to climate and land use changes,” he explained. 

These changes affect rainfall patterns and the movement of water across landscapes, with far-reaching implications for human well-being, including potential severe water shortages, food insecurity, and habitat degradation.

The study examined three future scenarios: a balanced economic growth model, a regional rivalry model with high energy use and moderate environmental concerns, and a fossil-fuel-driven development model. 

Each scenario paints a different picture of future water storage patterns and their impacts on global ecosystems.

However, Dr Oluwafemi noted the challenge in accessing long-term datasets necessary for understanding these patterns, due to limitations in monitoring infrastructure and financial constraints. 

Despite these challenges, climate models have emerged as vital tools in understanding the global water budget, although they are not without their limitations.

Dr Christopher Ndehedehe, a co-author and ARC Fellow at the Australian Rivers Institute, pointed out the limitations of climate models. 

“The limitations in climate models for capturing fine-scale details and microphysical processes due to oversimplification of real-world features magnify their biases,” he said. 

Correcting these biases is essential for accurate projections of future freshwater availability.

The study's findings reveal how seasonal changes in climate factors, such as shifting winds, affect water storage. These changes can lead to more frequent droughts or heavy rainfall, posing challenges for communities and ecosystems. 

Importantly, the research underscores the need for policymakers to consider the effects of water storage changes in their climate adaptation and mitigation strategies. 

The full study is accessible here.