AT THE POINT
Location: Degree Confluence 26°S 143°E is located in western Queensland, on the property ‘Raymore'. The closest settlement is Windorah, approximately 73 km to the north-west. The exact confluence was not reached, and instead data was taken at a site approximately 4.5 km to the north (25°73'S, 143°E). The site was visited in the early afternoon by a party of RGSQ members travelling in 4WD vehicles from Brisbane in November 2009.
Landscape: Elevation at the substitute site is 151 m, and the landscape is characterised by a flat plain with numerous drainage gullies. Surface material consists of small gibbers on top of sandy/clay loam. There is little vegetation at the site, excepting sparse, scrubby bushes, with only a few scattered mulga and other small trees. There were no animals at the site, although there is sheep and cattle of the property in the area. Human features include a property track and boundary fence, as well as other infrastructure nearby.
Kyabra Creek is the closest watercourse to both the confluence and the substitute site, which eventually drains into the Eyre Basin. Geology of the point is Winton Formation chemically altered sedimentaries such as sandstone, mudstone and siltstone (Upper to Lower Cretaceous in age, 145.5-65.5 million years ago).
Point Photos By: Paul Feeney
Point Information By: Paul Feeney, Jo Grant
IN THE DEGREE SQUARE
Climate: The closest representative weather station is at the Windorah Post Office, which is located 73 km north-west of the confluence, and has an elevation of 126 m. The station has been collecting data since 1887.
The highest temperature recorded was 47.1°C in December 1990, and the lowest was -1.8°C in July 1977. The greatest rainfall recorded in a year was 990.1 mm in 2000, and the least was 66.8 mm in 2002. These and other climate statistics for Windorah can be found at on the Australian Bureau of Meteorology website, http://www.bom.gov.au/climate/averages/tables/cw_038024_All.shtml
Extremes of Nature: The area is subject to the impact of some cyclones. The database maintained by the Bureau of Meteorology shows that since 1906 only 5 cyclones have tracked within 200 km of the confluence, none of which have passed within 50 km. These cyclones bring with them potentially destructive winds and intense rainfall. 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.
Cyclone tracks within 200 km of point 1906 to 2006 (Bureau of Meteorology web site)
Extreme heat and drought are also serious issues. Records show that Windorah experiences 124 days annually with temperatures over 35°C, 36 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 relatively little rainfall and only 36 days a year on average with any rain, the area is also among the driest in Australia.
Today: The population of the degree square is probably less than 50.
Edited by: Hayley Freemantle
Geoscience Australia, NATMAP Raster
Geoscience Australia, Scanned 250 K Geology Maps