Saturday, January 15, 2011

Floods in Australia

A Photo Survey
Some examples:


__________________________A masive plume of muddy water flows from the Brisbane River mouth into Moreton Bay. Photo: Bruce Long

From Germaine Greer:
Australian floods: Why were we so surprised?
...So, yeah, as Australians say, the problem is rain. The ground is swollen with months of it. The new downpours have nowhere to go but sideways, across the vast floodplains of this ancient continent. We all learned the poem at school, about how ours is "a sunburnt country . . . of droughts and flooding rains". Groggy TV presenters who have been on extended shifts, talking floods for endless hours, will repeat the mantra, so hard is it wired into the heads of Australian kids. And yet we still don't get it. After 10 years of drought, we are having the inevitable flooding rains. The pattern is repeated regularly and yet Australians are still taken by surprise.

The meteorologists will tell you that the current deluge is a product of La Niña. At fairly regular intervals, atmospheric pressure on the western side of the Pacific falls; the trade winds blow from the cooler east side towards the trough, pushing warm surface water westwards towards the bordering land masses. As the water-laden air is driven over the land it cools and drops its load. In June last year the bureau of meteorology issued a warning that La Niña was about "to dump buckets" on Australia. In 1989-90 La Niña brought flooding to New South Wales and Victoria, in 1998 to New South Wales and Queensland. Dr Andrew Watkins, manager of the bureau's climate prediction services, told the assembled media: "Computer model forecasts show a significant likelihood of a La Niña in 2010." In Brisbane the benchmark was the flood of 1974; most Queenslanders are unaware that the worst flood in Brisbane's history happened in 1893. Six months ago the meteorologists thought it was worthwhile to warn people to "get ready for a wet, late winter and a soaked spring and summer". So what did the people do? Nothing. They said, "She'll be right, mate". She wasn't....

One of the penalties of living on the east coast, as most Australians do, is that all the rain that falls on the mountains known as the Dividing Range heads your way. Up here, at the top of the watershed, I have only to fear a landslide, which will happen if slopes now bulging with water actually burst. At sea level, it's anybody's guess. Meteorologists and hydrologists try to predict peak levels and peak times, and have to revise their estimates up and down like yo-yos.

The world is aware of what has been happening in Australia because so much of Queensland's capital city, Brisbane, the "most livable city in Australia", is now submerged in dirty brown water. Smaller towns in Australia have been flooded for months; some have been flooded five times since the beginning of December. What the rest of the world must be asking is why Australians don't take steps to minimise the destruction? In the southern US you could take your Chevy to the levee; Australians rarely build them. An eight-metre levee has kept the town of Grafton dry, though the Clarence river is in massive spate, but Yamba, further downstream has no levee and is under water. Goondiwindi has an 11-metre levee to protect it from the Macintyre river, but hydrologists have predicted a peak of 10.85 metres – far too close for comfort. Evacuations have begun....

In the case of Toowoomba, Grantham and Murphy's creek, there was nothing to be done. The Lockyer valley suffered a flash flood, in which a sudden deluge generated an eight-metre wave of water that ripped through the towns, drowning people in their cars, popping houses off their stumps, and whirling them down stream. The resulting TV footage has been seen by Australians hundreds of times. It is the stuff of nightmares, with cars and buses bouncing end over end down streets full of people clutching at anything they can find to avoid being swept away. The army is now involved in searching for the bodies of the 61 people still missing; there is no more talk of rescue. The total dead to date is 26....

The colour of the water reveals a terrible truth. What is being washed downstream is topsoil. The water moves so rapidly because so much of the land has been cleared....When the settlers first arrived on the coast of northern New South Wales and southern Queensland, the rivers were navigable. As the "scrubs" (the settlers' way of referring to rainforest) were ripped out, the seasonal rains carried the topsoil into the rivers, which silted up and then began to flood.

The fresh water now entering the seas off Australia is expected to drift northwards to where the Great Barrier Reef is already struggling with rising sea temperatures. In ecological terms, worse, perhaps very much worse, is on the way. Australia owes it to the rest of the world to get a handle on its regular floods. Or she won't be right, mate.

The creatures of the rainforest are used to rain. After gorging on the treefrogs that are mating in a rainpool by the house, a night tiger snake has come up to sleep the day away on my verandah. A rufous fly-catcher is hunting for his breakfast under the verandah roof because there are no insects out in the rain. The regent bowerbird is enjoying his morning shower 50 metres up in the top of the quandong, meticulously grooming each gleaming feather.

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