The new year is off to a record-hot start in Australia, where blistering heat and wildfires
have torched southern and eastern parts of the country. Along
Australia’s southern coast, temperatures as high as 48ºC (119ºF) were
recorded last week. Yesterday, Australia’s average high temperature set
an all-time record of 40.33ºC (104.6ºF), according to the Australian Associated Press.
In a newly released climate statement,
Australia’s Bureau of Meteorology reports that this is the first time
Australia has ever recorded five consecutive days of temperatures above
39ºC (102ºF). Nationwide average temperatures on each of the first six
days of 2013 were among the top 20 hottest days on record.
The combination of heat and gusty winds has sparked deadly wildfires across southern and eastern Australia. The Associated Press reported
yesterday that officials were searching for 100 missing residents in
Tasmania, where fires engulfed several dozen homes. An island-wide ban
on all open-air fires is in effect for Jan. 8.
On the mainland authorities in New South Wales and Sydney have issued catastrophic fire warnings, as westerly winds of up to 50 mph blow toward the coast. The BBC reports that all national and state parks in New South Wales are closed to the public due to elevated fire danger.
Australia’s Bureau of Meteorology has said
that the current heat wave is a culmination of abnormally warm
temperatures seen in late 2012. In the most recent September-December
climate period, the nationwide average maximum temperatures were 1.61ºC
above normal. This is slightly higher than the previous record
temperature anomaly of +1.6ºC set in 2002 (with records dating back to
1910).
The bureau also writes that the current heat wave is unique for its “exceptional spatial extent of high temperatures.”
How did the heat wave start? During the final week of
2012, a high pressure system developed in the state of Western
Australia. The sprawling heat dome then expanded eastward, which
directed extremely hot air out of the Australian interior into coastal
areas less accustomed to high temperatures.
Eucla, along Australia’s southern coast, reached 119ºF on Jan. 3, its
hottest day since records began in 1957. For perspective, the average
high in this coastal town in January is only about 79ºF (26ºC).
A sampling of other high temperature records (previous record in parentheses):
* 48.2 ºC / 119 ºF in Eucla, Western Australia (47.9ºC on Jan. 3, 1979)
* 46.3 ºC / 115 ºF at Leigh Creek Airport, S. Australia (46.1ºC on Jan. 25, 2011)
* 44.1 ºC / 111 ºF in Adelaide, S. Australia (44.0ºC on Jan. 28, 2009)
* 41.8 ºC / 107 ºF in Hobart, Tasmania (40.8ºC on Jan. 4, 1976)
* 46.3 ºC / 115 ºF at Leigh Creek Airport, S. Australia (46.1ºC on Jan. 25, 2011)
* 44.1 ºC / 111 ºF in Adelaide, S. Australia (44.0ºC on Jan. 28, 2009)
* 41.8 ºC / 107 ºF in Hobart, Tasmania (40.8ºC on Jan. 4, 1976)
Several record-high minimum temperatures were also recorded, including 27.5ºC (81.5ºF) in the western city of Perth on Dec. 29 and 23.4ºC (74ºF) in Hobart, Tasmania on Jan. 4.
As the heat expands eastward, temperatures will soar along the
usually temperate southern and eastern coasts. In Sydney, temperatures
climbed to at least 42ºC (107ºF) on Tuesday. While Sydney’s all-time record high
of 45.3ºC (113.5ºF) remained safe for now, temperatures have eclipsed
43ºC (109ºF) on only three days of Sydney’s 150 years of weather
records.
Fortunately, the heat will retreat from the eastern
coast on Wednesday, bringing temperatures down to more seasonable
levels. But temperatures may spike again this weekend. And in the Australian interior, hot, dry conditions will make bushfires an ongoing threat.