Intensifying droughts brought on by climate change, pose alarming threats to Australia’s food and water security, according to a Climate Council report to be launched today at parliament house.
The report warns that the nation’s agricultural yields may suffer if climate action is not taken, and raises the prospect of serious water insecurity in major cities.
Perth is likely to be hard-hit, with research showing an already precarious water supply could diminish with rapidly.
Annual stream-flow into the city’s dams has dropped by 80 per cent since the mid-1970s, and demand for water is projected to outstrip supply by as much as 85 billion litres – or around 34,000 Olympic sized swimming pools – by 2030.
Professor Will Steffen, who authored the report, told New Matilda that Perth is already looking at desalination, which is “expensive to do and requires a lot of energy”,
According Professor Steffen’s findings, Western Australia could face reductions in Autumn and Winter precipitation of around 50 per cent in the next 80 years.
The changes are largely brought on by fronts from the Southern Ocean – which trigger rain during Winter and Spring – shifting southwards and increasing the risk of drought across southern Australia.
Southeast Australia has already experienced a 15 per cent decline in late autumn and early winter rainfall since the mid-1990s, and a 25 per cent decline in average rainfall in April and May.
In Sydney, water inflows for key dams like Warragamba and Shoalhaven could decrease by as much as 25 per cent by 2070 if greenhouse gas emissions continue on their current trajectory, according to the report.
Melbourne could see annual stream flows lower water harvesting storages by seven per cent by the end of this decade, and 18 per cent by mid-century.
With Australia’s population growing faster than comparable developed countries, Professor Steffen said, “the challenge now is how do you over the next coming decades transform away from carbon reliant energy systems”.
It’s a task he says needs to be largely complete by mid-century to mitigate the serious impacts detailed in the report.
The findings outlined in the Climate Council report show that the already serious economic consequences of drought will become a greater challenge in the future.
Between 2002 and 2003, the report found, a severe drought led to a one per cent drop in GDP, equivalent to half of Australia’s decline in annual GDP following the global financial crisis in 2009.
In the same 2002-2003 period, gross added value for the agricultural industry was down 28.5 per cent on the previous year, and by my mid-2010 the Australian government had paid out $4.4 billion in direct drought assistance to farmers.
Australia is known for its agricultural exports, but Professor Stephen said that as drought stifles agricultural productivity and the population continues to grow, Australia could become a food-importer by 2050. As Australia and the world prepare for the Paris climate talks later this year, today’s Climate Council report brings into focus the material impacts climate change will have.
Last week, the Abbott government released an issues paper which canvassed some of the considerations that will influence the post-2020 target, due to be announced mid-year.
The paper reiterated the government’s argument that Australia’s contribution should take strong account of the nation’s structural dependence on coal exports, but Professor Stephen said that argument “doesn’t have much merit at all”.
“As economic and technological change occurs elsewhere, we’re not going to be able to advantage of opportunities,” he said.
The focus, Professor Steffen argues, needs to be on decarbonising the economy by mid-century; a task that will require deep cuts to carbon emissions from all nations.