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Statement on Drought for the 4, 7, and 11-month
periods ending 30th November 2006
Drought intensifies over eastern and southern Australia
Rainfall deficiencies have
been gradually spreading over eastern and southern Australia during
2006, but the situation has taken a distinct turn for the worse from
August, with a near total failure of the late-winter and spring rains.
In the historical record dating from 1900, it was the driest August
to November period averaged across SA, the second driest averaged over
the Murray Darling Basin, the third driest across Australia and the
fourth driest for Victoria. Rainfall deficits have also developed over
parts of the tropics as evidence of a poor start to the northern wet
season.
It has also been remarkably warm over this period as well, with mean
maximum temperatures being the highest on record (for the post-1950
era) averaged over Australia, Victoria, SA, WA and the Murray Darling
Basin. Over NSW and the NT maximum temperatures were the second highest
on record.
Rainfall deficits are also evident over other agriculturally sensitive
periods during 2006: the period since May has been very dry across much
of southern and western WA (as well as in the southeast of the country),
while for the period beginning in January, southeastern Australia
(including Tasmania), southeast Queensland and a coastal strip in
southwest WA are affected by severe rainfall deficiencies .
For the 4-month period from August to November,
generally severe rainfall deficiencies covered most of the southern
two-thirds of SA, all of Victoria, northern and eastern Tasmania, most
of NSW west of a line from Bega to Tamworth to Bourke, much of
Queensland’s western half, pockets along the south coast of WA and
large areas in the northern half of the NT. Significant regions have
had their driest August to November on record - especially over central
SA extending into the far northwest of NSW and far southwest of
Queensland, and also the tablelands and western slopes between the ACT
and Dubbo in NSW. Record low totals also occurred around Esperance in
southern WA.
For the 7-month period from May to November,
severe rainfall deficiencies cover most of western and southern WA,
although average to above average rainfall during November caused a
modest decrease in the extent and intensity of the deficits in
comparison with the situation at the end of October. Also experiencing
deficits for this period are SA southeast of a line from Ceduna to
Marree, Victoria (apart from East Gippsland), much of NSW west of the
Divide and south of about Tamworth, the southeast inland of Queensland
centred on about Miles, and northern and eastern Tasmania. Numerous
small regions, mainly near the coast, have registered record low totals
for this period.
Since the start of the year, i.e. the 11-month period from
January to November, serious to severe rainfall
deficiencies affect southeast Queensland away from the coast, much of
the southern half of NSW west of the ranges, Victoria (apart from far
East Gippsland), northern and eastern Tasmania, southeastern SA and a
coastal strip in WA from Carnarvon to Albany. In addition, parts of
the interior between Bourke and Alice Springs also have deficiencies
for this period. Record low falls are analysed along Tasmania’s north
coast and in the mountainous regions of northeast Victoria and southeast
NSW, extending into parts of the southwest slopes.
The deficiencies discussed above have occurred against a backdrop of
multi-year rainfall deficits that have severely stressed water supplies
in the east and southwest of the country.
Rainfall
deficiency maps for standard periods out to three years are
available.
Note: The terms used to describe rainfall in these
Drought Statements have the following meanings -
Serious deficiency
- rainfalls in the lowest 10% of historical totals,
but not in the lowest 5%
Severe deficiency
- rainfalls in the lowest 5% of historical totals
Lowest on record
- lowest since at least 1900 when the data analysed begin
Very much below average
- rainfalls in the lowest 10% of historical totals
Below average
- rainfalls in the lowest 30% of historical totals,
but not in the lowest 10%
Average
- rainfalls in the middle 40% of historical totals
Above average
- rainfalls in the highest 30% of historical totals,
but not in the highest 10%
Very much above average
- rainfalls in the highest 10% of historical totals
For more information regarding this rainfall
deficiencies statement, please contact the following
climate meteorologists in the National Climate Centre:
Grant Beard on (03) 9669 4527
Blair Trewin on (03) 9669 4623
David Jones on (03) 9669 4085
External Sites Relating to Drought
The Bureau of Meteorology does not make formal drought declarations
as these are done by either the relevant State Governments or by the
Australian Government. The Australian Government Program is called
Exceptional Circumstances
and it is administered by the Federal Department of Agriculture,
Fisheries and Forestry (DAFF). General information about Australian
Government drought assistance is available at
http://www.daff.gov.au/droughtassist.
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