(AU ABC) Is Climate Change Behind Record-Breaking Temperatures In The Pilbara?

ABC Pilbara - Laura Birch

The Bureau of Meteorology says there has been an increase in the frequency of extreme heat events in Australia due in part to climate change.

The temperature soared to 50.7C at Onslow, in the Pilbara, on Thursday. (ABC Pilbara: Laura Birch)

Key Points Three towns in the Pilbara surpassed 50C this week The Bureau of Meteorology says a build-up of hot air led to the extreme weather event, but climate change could also be a factor Climate expert Jatin Kala says it is alarming how many record weather events are occurring

This week Onslow, 1,377 kilometres north of Perth, reached 50.7 degrees Celsius.

It equalled the hottest temperature ever recorded in Australia and the Southern Hemisphere.

Also in the Pilbara region, the mercury soared to 50.5C in Roebourne and Mardie.

Previously, temperatures had only exceeded 50C three times in Australia's history.

BOM duty forecaster Jessica Lingard said while it was hard to pin climate change as the sole reason for temperatures spiking in the Pilbara this week, it could be a factor.

"If we look back at the 2019 climate report which was published by the bureau and the CSIRO, that showed there has been an increase in the frequency of extreme heat events and record high temperatures," Ms Lingard said.

She said the Pilbara could experience these high temperatures more often.

Freja Harmer cools off as Onslow experiences record-breaking temperatures. (Supplied: Shane Harmer )

What caused the hot weather in Onslow? Ms Lingard said it was unexpected a town on the coast of Australia would reach 50.7C.

"We normally expect to see our hotter temperatures further inland because they don't have the coastal, cooling effects of having an ocean nearby," she said.

Australia's hottest day

Onslow, around 1,400 kilometres north of Perth, joins Oodnadatta in outback South Australia, which hit 50.7C in January 1960. Read more

"What happened was we had a very hot air mass over WA and then we had really strong offshore winds.

"Winds blowing from the centre of Australia out over the ocean, and they blocked the usual arrival of [the] cooler sea breeze."

This allowed the temperatures to continue to increase.

"Looking forward in the next year or two, or even in the next decade we may start to see these hotter temperatures becoming more frequent as I say due to the implications of climate change," Ms Lingard said.

Is climate change a factor? Murdoch University senior lecturer in atmospheric science Jatin Kala said he was concerned about the frequency of these record-breaking temperatures.

"If you look at the past decade, I think about seven of the hottest years on record have happened in the last decade," he said.

"Out in the Pilbara it does get very hot, that's not unusual.

"What is really concerning is the rate at which these records are being broken."

Dr Kala said it showed the global climate was warming rapidly. Curtin University climate change expert Ashraf Dewan said it was difficult to say whether the record-breaking temperatures in the Pilbara were the result of climate change.

"That might be an indirect effect of climate change because that region is experiencing low rainfall," he said.

But Dr Dewan said extreme and random weather patterns would become more common in the future.

'If we can't control the emissions that may actually lead to new temperature records every year, we don't know," he said.

Dr Kala said there needed to be concerted action globally.

"As we increase the concentration of greenhouse gases in the Earth's atmosphere we generate more warming and as we warm the mean global temperature we're going to get more regional extremes," he said.

"We need politicians to listen to the science and we really need to curb down our emissions of greenhouse gases to net zero as soon as we can."

The WA Minister for Climate Change has been contacted for comment.

Links

• (AU The Conversation) This WA Town Just Topped 50℃ – A Dangerous Temperature Many Australians Will Have To Get Used To
• (AU ABC News) Why WA's South-West Is Drying Out At One Of The Worst Rates In The World
• (The Conversation) Ocean Heat Is At Record Levels, With Major Consequences
• (Common Dreams) The Climate Emergency Is 'Now': Over 400 Weather Stations Set New Heat Records In 2021
• (AU The Guardian) ‘Extreme Marine Heatwave’: Waters Off Sydney Set To Break January Temperature Records
• Small beachside town in WA equals Australia's hottest day on record
• Extreme heatwave threatens to deliver December scorcher like no other
• Impending heatwave could turn 'Australia's hottest town' into the hottest place on Earth