ACT News

No heatwaves, but Canberra summer has still been hotter than average

A lack of extreme temperatures in Canberra has led many to question where our summer has disappeared to, despite official records showing this season has been hotter-than-average.

Sean Carson from the Bureau of Meteorology said lack of extreme heat in Canberra this summer was due to a couple of tropical weather systems, which moved through the interior of the country brining rain in the second week of January.

"This has eroded the large mass of heat that was building up across inland Australia," he said.

Despite the lack of heatwaves, Mr Carson said temperatures in Canberra have been 1.1 degree above the summer average at 28.1 degrees.

"So far December 2nd was 33 degrees and January 2nd was 35 degrees. But that's compared to last summer where we had four consecutive days of 40 degrees and three consecutive days of 39 degrees in February," he said.

Mr Carson said it would take a few weeks of clear conditions in central Australia before temperatures would begin to increase to more extreme levels.

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"We are seeing signs that this is occurring with temperatures in the high 40's through the Gascoyne area of Western Australia this week, it is very unlikely however that this mass of hot air will affect the southeast of the continent before the end of January."

According to the Bureau of Meteorology, temperatures are expected to reach 32 degrees on Friday and remain around 30 degrees until Sunday with scattered showers.  

While conditions have been warm this summer they've also been wet.

"Currently Canberra has seen 196mm of rain for the summer so far and the summer average is 169mm, so we have already exceeded this with 37 days still to go," Mr Carson said.

Mr Carson said the tropical conditions in early January had increase soil moisture and humidity, which resulted in a favourable environment for thunderstorm activity

"El Nino thresholds were approached in spring and this was reflected with a very hot and dry spring locally, and the hottest on Australian record," he said.

"However with the Pacific Ocean showing that the ENSO cycle is trending back to neutral values, we can expect the 3 monthly outlooks for temperature and rainfall to be closer to long term climatological averages."

Earlier this month the Bureau of Meteorology declared 2014 the third hottest year on record just 12 months after 2013 smashed annual highs.

Mean temperatures across the country last year came in 0.91 degrees above the 1961-1990 average, behind only 2013 and 2005.

"A number of prolonged and geographically extensive warm spells affected Australia during 2014, resulting in monthly records for highest temperature being set at numerous locations," the bureau said in its annual climate statement.

Climatologists say background conditions are warming as a build-up of greenhouse gases traps more of the sun's heat in the atmosphere, making it increasingly likely that heat rather than cold records get broken.

"Global warming is contributing to these heat records, and it's very unlikely that we would have seen the proliferation or the frequency of these heat records around the world without the influence of global warming," Karl Braganza, head of climate monitoring at the bureau, said.

"The climate system we live in...that's all about 1 degree warmer than it used to be," Dr Braganza said.

With Peter Hannam

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