ARTICLES
Stimulus Material for depth studies, courtesy of Macquarie University (continued)
How the rivers run cancers
Rivers within the Murray-Darling Basin have significantly declined in size and flow over the last 100,000 years,
according to new research from Macquarie University’s Department of Environmental Sciences.
“We found that some rivers had channels up to 12 times wider, and carrying up to 270 times the flood discharge
of their modern equivalents,” says lead author Paul Hesse.
“And for the first time we’ve demonstrated that temperature is a principal driver of river flow, rather than changes
in precipitation.”
The researchers used modern rainfall and river flow data to examine the climatic drivers of river flow and the
size of the river channels, and derived an equation to best describe the relationship between rainfall and river
flow.
They used this to predict hydrology for ancient rivers across the Murray-Darling Basin from the large ancient
channels still visible on the surface of the alluvial plains.
“This research is impactful as it uses knowledge of the past as a window for the future,” says study co-author
Tim Ralph.
“The Murray-Darling Basin is Australia’s food bowl, and so understanding the key drivers of river hydrology is
imperative now and into the future.
“Our work suggests that the Murray-Darling Basin river system is likely to be highly sensitive to future
temperature change.”
The research was published in Quaternary Science Reviews.
Find out more
Syllabus link: E
arth and Environmental Science. Module 4: Human Impacts
FACULTY OF SCIENCE
AND ENGINEERING
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SCIENCE EDUCATIONAL NEWS VOL 68 NO 1