26°S 140°E Lake Cooninnie – Queensland by Degrees

AT THE POINT

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Degree confluence 26°S 140°E, Google Earth

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n

Looking north

e

Looking east

s

Looking south

w

Looking west

Location: The site is in south-western Queensland, adjacent to the Qld-SA border. The area is in a strip of low-lying land made up of usually dry creeks, lake beds and flats that trends towards the Diamantina River in the south-west. The wider region is part of Queensland's Channel Country.

The degree confluence (with no official marking) is found on the eastern margin of a small dune field, and north-east of Lake Teetatobie and Lake Coninnie. Several hundred metres to the north of the confluence the remains of an old east-west fence can be found (perhaps the old border fence or rabbit fence). Sand is piled up along the old fence line to a height of about half a metre to a metre. Like Queensland's other borders, there is a discrepancy between the specified latitude or longitude and the officially mapped border. Access to the point is by a property track (about two-thirds km to the north), and then by going 'cross-country'. The nearest settlement is Birdsville (Qld), about 66 km in a straight line to the west (and slightly north). The site was visited by a party of RGSQ members travelling in four 4WD vehicles from Brisbane in May, 2008.

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Degree Confluence 26S 140E from a nearby dune

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(Looking south-west) (People at confluence) Remains of old fence line - border or rabbit fence (running east-west to the north of confluence).

Landscape: The point is located on a small salt lake of 200m length (along its greatest axis), on the south-east edge of a relatively small dune field. The larger Lake Teetatobie is visible to the south-west. Between tussocks growing on the dune nearest the lake (100 m west) are bare parts that are subject to wind action. Numerous other small and larger salt lakes are nearby. Scattered low trees (up to 4 - 5m) are dotted around the lake shore and on the dune. Natmap (250K Raster Maps) indicates that the adjacent area subject to inundation contains a low spot height of 48m (this lies 2.6km to the east). The nearby dune field indicates heights of several metres higher. Geological features around the confluence point include Cainzoic sand, and underlying Cretaceous sedimentary rocks (marine environment) (Scanned 250K Geology Maps, Geoscience Australia).

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Google Image: dry lake and nearby linear dune, Degree Confluence 26°S 140°E

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Google Image: Lake Teetatobie and linear dunefield adjacent to Degree Confluence 26°S 140°E
Fence line visible in northern part of image

Point Photos: Paul Feeney, Mary Comer

Point Information By: Col & Jo Grant

 IN THE DEGREE SQUARE

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Climate: The closest representative weather station to the confluence is at the Birdsville Police Station. It has an elevation of 47m, and has been recording data since 1892.

 

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

Mean max
(ºC)

38.8

37.8

35.1

30.3

24.8

21.6

20.8

23.5

28.1

32.1

35.5

37.7

30.5

Mean min
(ºC)

24.2

24.1

21.1

16.2

11.3

7.9

6.6

8.3

12.2

16.1

19.7

22.5

15.8

Mean rain
(mm)

24.7

29.0

16.4

9.5

11.8

10.4

10.9

6.4

5.7

12.1

13.7

16.0

167.2

The highest temperature recorded was 49.5°C in December 1972, and the lowest was -1.7°C in June and July 1965. The greatest rainfall recorded in a year was 541.8 mm in 1916, and the least was 33.2 mm in 1913. These and other climate statistics for Birdsville can be found at: Australian Bureau of Meteorology, http://www.bom.gov.au/climate/averages/tables/cw_038002_All.shtml

Extremes of Nature: Since 1906 there have been no cyclones to pass within 50 km of the degree confluence, but 3 within 200 km (1964, 1976, 1995). Cyclone information for this area and all of Australia can be found at the Australian Bureau of Meteorology website, http://www.bom.gov.au/cgi-bin/silo/cyclones.cgi

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Cyclone tracks within 200 km of the confluence, 1906 to 2006 (Bureau of Meteorology web site)

Extreme heat and drought are also serious issues. Records show that Birdsville experiences 113 days annually with temperatures over 35°C, 45 of which typically reach 40°C or warmer. Such extreme temperatures can cause heat stroke and death if appropriate measures are not taken such as avoiding strenuous physical effort, keeping as cool as possible and drinking lots of water. Heat waves kill more people in Australia than all other natural hazards combined. In addition, with very little rainfall and only 23 days a year on average with any rain, the area is also among the driest in Australia.

Today:

The total population of the degree square at the 2011 national Census was probably less than 50. The fluctuation in population numbers is largely due to changes in census boundaries rather than actual shifts in population numbers.

MEASURE

1996

2001

2006

2011

Total population

274

206

115

<50?

Total males

149

103

60

?

Total females

125

103

55

?

Under 5 years

16

15

9

?

65 years and over

29

28

7

?

Indigenous

61

37

38

?

Edited by:  Hayley Freemantle

REFERENCES

Geoscience Australia, NATMAP Raster

Geoscience Australia, Scanned 250 K Geology Maps