Tuesday, June 24, 2008

Fiddling and Burning: the corrosive death of the Murray

Imagine Brazil without the Amazon, Egypt without the delta, and a Mississippi missing more than just its four ‘i’s. As implausible as these ideas seem, that seems to be exactly the fate of Australia as a slow truth emerges that the Murray-Darling Basin is almost beyond salvage. The loss would be profound. This astonishing network of water drains one seventh of an arid continent, is over 3,000 kms long, meanders through four states, houses ten percent of the nation’s population; and is the dairy, grain and fruit bowl to half the country. The Murray-Darling Basin is an effective food provider but is a thirsty consumer of water. 70 percent of all Australia’s irrigation takes place in the shadow of Murray floodlands. But now the party is coming to an end. The Murray rivermouth is dying and the nearby lakes are turning acidic.

An acidic river is not a happy specimen. The acid is sulphuric, caused when underwater soils become exposed to the sun. You would not want to wade in a sulphuric acid river, because it is capable of burning flesh. Acidity is also the last stage before a river dies and and there is no known cure. Today, a briefing of scientists was told that if the Council of Australian Government (COAG) didn’t act on the problems in their meeting next week, “we're going to confront an environmental and human catastrophe the like that which we have not seen or even imagined possible 20 years ago.”

The speaker was Peter Cosier of the Wentworth Group of Concerned Scientists. Cosier is concerned and he is a passionate campaigner on water. Two weeks ago Cosier was a home town key-note speaker at a Conservation Council of South Australia water policy summit. In his speech (pdf) he described himself as someone who spent much of his professional career fighting for a healthy Murray. He called his audience a “preselected group of people” who were a rare antidote to the bewildering silence elsewhere in Adelaide at the nature of the disaster that lies ahead.

Cosier believes that the current strategy for dealing with drought-related problems is best described as “praying for rain”. He says this autumn has been the fourth-driest on record for the Murray-Darling basis while the river system is in serious decline. Some dairy farmers in NSW are facing a zero water allocation in the irrigation season for the fourth year in a row. This will mean many farms will go under as they have no water to use for irrigation.

But lack of rainfall is not a new problem for a continent prey to the El Nino Southern Oscillation (ENSO) weather patterns. Rainfalls have been this low in the past but the river has never been this low. What is new is global warming, as even the usually sceptical The Australian admits. Murray Darling Basin Commission head Wendy Craik told the paper’s rural writer Asa Wahlquist that the higher than average temperatures were causing higher evaporation. Craik says that a rise in temperature of just 1 Celsius each year causes a 15 percent reduction in the river flow. The past three years in the basin were the warmest on record, with last year the warmest yet at 1.1C above average. If Craik’s calculations are correct, there’s almost half the river gone in the last three years alone.

The health of the river affects doesn't just affect humans. The Coorong wetland at the very bottom of the Murray Darling Basin is so hyper saline, that organisms can no longer live in it. Migratory bird numbers are also in freefall. The river system is home to one million shorebirds who begin their 10,000km migration to Siberia from the bottom end of Australia. But a new large scale aerial survey study covering the eastern third of the continent by researchers at the University of New South Wales shows the population has plunged by 75 per cent since 1983. That’s three-quarters of all birds that have disappeared in one generation. Co-author of the study Professor Richard Kingsford says loss of wetlands due to river regulation is a main contributor to the mystery. “But it appears,” he said, “such a threat is largely unrecognised in Australia's conservation plans and international agreements.”

It is unsurprising that birds, like humans, would not thrive in a corrosive environment. Evidently, praying for rain is no substitute for good policy. This will not be easy problem to solve, as witnessed by a century of inaction and almost wilful neglect. And science is not yet agreed on an answer to the problem of southeast rainfall decline. Chris Mitchell would know more than most. He is the director of the Centre for Australian Weather and Climate Research, a partnership between CSIRO and the Bureau of Meteorology. Mitchell's advice is simple. He says we must simply adapt to a drier climate and manage the system according to that downturn.

But as Peter Cosier insists, that means acknowledging the anthropic involvement in global warming. Its extremely likely if the current level of inaction and lack of global political will continues, temperatures will increase by an average four degrees worldwide by the year 2100. This would be the warmest average temperatures on Earth in 40 million years. Even if the world agrees to IPCC’s hopes of cutting global greenhouse emissions by 70 percent in 2050, Cosier says the planet will still be a drastically different place thanks to climate change. Fellow South Australian Gary Sauer-Thompson says the river is dying from the mouth up and the combination of salt and acid will move upstream and progressively contaminate the lower Murray. Cosier says solutions are available, but the pace of political reform is too slow. “We need a long term solution for the lower lakes and we need it before this summer, he said. But he warned his audience they would have to take action themselves to make it happen. “There is no “they”, there is only us,” he said.

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