Saturday, December 16, 2006

Lfe in a parched land.

Here in Queensland’s ‘Western Downs’ with temperatures hovering around the mid 90's (35c) the first distant cracks of thunder were welcome for the relief a storm might bring in. Out to the west we could see sheets of rain falling, but the storm itself appeared to be wandering a bit.

When the storm finally hit it was with a sort of clichéd Hollywood effect, a violent clap of thunder followed seconds after by torrential downpour. The downpour eased off quickly, followed twice by the cliché thunder clap, until the rain settled in.

As the storm hit the wind came in violently from the south west, but quickly turned and drove the squalls from the west, horizontal rain squalls. I missed a few minutes of the storm and came back to a howling east wind which eventually moved to a south wind.

So in a half hour of dramatic electrical storm we also experienced a sort of mini tornado – or cyclone here. There were a few more storm cells around the horizon as well, with lightning flashes into the night. In that half hour we received 44 points of rain – that is 11 mm or just under half an inch. There was just one mm added overnight.

According to the rain book in this house here the rainfall for the year to date is 375 mm or 15 inches.

Agriculturalists say; areas in southern Queensland have only half full moisture profiles, while some areas of the Western Downs and south west are down to 30 per cent of the potential soil moisture profile.

In this area, an average dry soil requires about 600 mm a year. In yesterdays storm the water sat on the dry surface for nearly an hour before eventually soaking in. Had it kept raining at that rate we would have experienced flooding as the surface water just ran off.

More rain today, after the surface wetting, would start to build some ground storage, but it is unlikely to happen.

Australia is suffering a worst in 100 years drought, some make that figure 1000 years. Whether it is global warming or just cyclic is open to debate, but there have been some interesting approaches, in the past few years, to mitigating the effects of drought and flood. One I heard of would even help in the ever present bush fire danger.

The exact details I don’t recall, but I farmer or perhaps horse breeder in the Hunter Valley on the central coast of NSW discovered the benefits of reverting his land to its natural tendencies. In part that meant doing away with ditches and dykes and allowing natural wetlands to develop.

Sure he lost pasture land, but his argument was, if the soil is too dry to support decent pasture then it was no real loss. By reintroducing wetlands to the property the water tables are coming back to proper balance and remaining pastures are lush. Somehow the wetlands also cut out the dangers of serious flooding, presumably because the soil is damp enough to allow for soakage.

I notice here in this inland Queensland town, the local creek isn’t much more than a string of water holes at present. I expect much of it is flowing underground. But I have also noted that parts of the creek are being encouraged to develop back into wetlands. That is obviously great news for the abundant birdlife out here, though I can’t see it helping broad acre farmers.

Apart fro a few straggly cattle I haven’t seen many signs of agriculture. I’m told there are cotton and ranching operations nearby. All I’ve seen are mobs of kangaroos.

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