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For the 9 and 18-month periods ending 30th November 2008
Rainfall deficiencies ease over much of Australia
LINKS:
rainfall deficiencies definition
9-month rainfall deficiencies
18-month rainfall deficiencies
Above to very much above average November 2008 rainfall over much of Australia
largely cleared short-term rainfall deficiencies, especially over the NT, SA and WA. However, average to
below average falls in western Victoria into southeastern SA maintained deficiencies in these areas.
For the 9-month period from March to November 2008, above to very much above average rainfall during November has resulted in a general easing of short-term rainfall deficiencies. This was especially evident over southern parts of NSW, northern NT into western Queensland and the southwestern corner of the NT into southern WA and central to southern SA. Below average falls in western Victoria into southeastern SA have maintained deficiencies in these areas. Above to very much above average rainfall fell in eastern Victoria, however, the previous severity of deficiencies in these areas means that they are still present for the period, although they have eased in severity and spatial extent. Generally, areas of serious to severe rainfall deficiencies have persisted over much of southern Victoria (extending into southeastern NSW and the far southeast of SA) and eastern Tasmania. However, there has been a marked decrease in the size and severity of these deficiencies. Small patches of rainfall deficiencies persist in southern SA, northern NT and western Queensland.
Rainfall deficiencies for the 18-month period from June 2007 to November 2008 have also eased over large areas, corresponding to the regions that recorded above average rainfall during November. This general easing of long term rainfall deficiencies is not as extensive as was seen for the short-term. Large areas of deficiencies still persist across southern SA into western Victoria. Areas of severe deficiencies have eased somewhat over these areas, although areas of lowest on record still persist in southern SA and have expanded to small patches in southeastern SA. The large area of lowest on record has cleared over eastern Tasmania, although severe deficiencies still persist in eastern and northern Tasmania. Following the very much above average November falls in the southern NT and southern WA deficiencies have largely eased in these areas, however, an area of serious to severe deficiencies still persists in southern parts of the NT.
The deficiencies discussed above have occurred against a backdrop of decade-long rainfall deficits and record
high temperatures that have severely stressed water supplies in the east and southwest of the country.
The combination of record heat and widespread drought during the past five to ten years over large parts
of southern and eastern Australia is without historical precedent and is, at least partly, a result of climate change.
For more information go to a recent
Special Climate
Statement on the long-term drought in southern Australia "Long-term rainfall deficiencies continue in southern Australia while wet conditions dominate the south",
issued 10 October 2008. A dry October over much of southeastern Australia has, in many cases, increased the magnitude of the three and seven year records
at the stations identified in the statement, and more stations have set three-year records, especially in Tasmania.
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:
Lynette Bettio on (03) 9669 4165
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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