Australia has started 2013 with a record-breaking heat wave that has lasted more than two weeks across many parts of the country. Temperatures have regularly gone above 48°C, with the highest recorded maximum of 49.6°C at Moomba in South Australia. The extreme conditions have been associated with a delayed onset of the Australian monsoon, and slow moving weather systems over the continent.
What is causing Australia's heatwave?Does the country's record-breaking heatwave have something to do with climate change?
Australia has always experienced heat waves, and they are a normal part of most summers. However, the current event affecting much of inland Australia has definitely not been typical.
The most significant thing about the recent heat has been its coverage across the continent, and its persistence.
It is very unusual to have such widespread extreme temperatures — and have them persist for so long. On those two metrics alone, spatial extent and duration, the last two weeks surpasses the only previous analogue in the historical record (since 1910) – a two-week country-wide hot spell during the summer of 1972-1973.
A good measure of the spatial extent of the heat is the Australian-averaged maximum daily temperature. This is the average of the highest daily temperature of the air just above the surface of the Australian continent, including Tasmania. The national average is calculated using a three-dimensional interpolation (including topography) of over 700 observing sites each day.
On Monday and Tuesday last week (January 7 and 8) that temperature rose to over 40°C. Monday's temperature of 40.33°C set a new record, beating the previous highest Australian daily maximum of 40.17°C set in 1972. Tuesday's temperature came in as the 3rd highest on record at 40.11°C.
Tuesday, January 29, 2013
Australia on the Front Line
Fascinating overview of Australia's record breaking temperatures. From The Guardian: