Sunday, 4 March 2012

More on Rain

Click on the following URL to get a good impression of where rain has fallen in the last week:


The most amazing things are:
1      The 300mm (12 inches) of rain around Alice Springs in the centre. The Alice wouldn't get that much in a normal year;
2      The > 200mm (8 inches) in and around Canberra in the southeast;
3      The band of heavy rain diagonally across the country;
4      Our dry spot in Northern NSW;
5      The torrential rain in a slim band along the rainforest coast of North Queensland (near Cairns);
6      The active monsoon conditions across the northern third of the continent; and
7      The mostly dry conditions in the southwest corner of WA.

In NSW, something like 2/3rds of the state is flood affected in some way or other - a vast area. Our corner of the state has had heavy rain for months and all that water is still making its way down the Darling river system. Southern Queensland was flooded a few weeks ago and that water is also heading downstream. To repeat earlier postings, all this water can take 3-4 months to reach the sea because the rivers are graded so gently. Moree's altitude is 212m (c. 650 feet). A lot of places in the UK with that altitude might be 30 km from the sea. Moree is 750km from the sea in a straight line and perhaps 1500 km after allowing from bends and deviations. Simple arithmetic reveals that the land falls on average 1 meter (or > half my height) every 7km. That's flat.

I was told about a flood that hit the town of Hay in the SW of this state along time ago. It was so strong it tore quite a large vessel from its mooring on the river bank. After the flood peak had passed by residents went looking for the craft and eventually found it 20km (12.5 miles) from the river.

AS

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