While Australians are used to summer heat, most of us only have to endure the occasional day over 40℃.
Yesterday was much cooler. Peak at 50.7℃Onslow, a small Western Australian village located approximately 100km from Exmouth.
It is remarkable that the town is right next to an ocean, which can provide cooling. Marble Bar, a notoriously hot WA town, is the exception. Only 49.6℃Despite its inland location, this summer was amazing.
If confirmed, the Onslow temperature would equal Australia’s hottest on record Set in OodnadattaSouth Australia, January 1960. It would also mark only the fourth day over 50℃ for an Australian location since reliable observations began.
This extreme heat is becoming more frequent as the world heats. The number of days over 50℃ has The 1980s saw a doubled increase in the number of people who have gotten married.. These dangerous temperatures can be found now Recorded more often – not just in Australia but in cities in Pakistan, India and the Persian Gulf. These conditions pose serious health risks to those who are subject to them.
Where did the heat come?
To reach such extreme temperatures, heat must build up over several day.
Onslow’s temperatures had been Close to the averageSince the second half December, there have been a few heatwaves in the Pilbara. So where did this unusual heat originate?
In other words, from the desert’s baking heat. South-easterly winds carried very hot air from the interior to Onslow. The wind was from an area that had not received much rainfall since November. Therefore, the extremely hot air was extremely dry.
The sun beat at its maximum intensity when dry air was present. This prevented any storm formation or cloud cover. The result? The temperature rose and rose through the morning and early afternoon, and the temperature spiked at over 50℃ just before 2.30pm local time.
Aren’t we in a cooler La Niña period?
Australia’s weather is strongly linked to conditions in the Pacific Ocean. At the moment we’re in a La Niña eventThe central and east Pacific have cooler than normal ocean temperatures.
La Niña is typically associated with cooler, wetter conditions. However, its effects on Australian weather can be quite significant. Strongest in springWe had an unusually high number of guests. Wet and cool conditionsOver the east coast of the continent.
During summer the relationship between La Niña and Australian weather usually weakens, with its strongest impacts normally confined to the northeast of the continent.
During La Niña we typically see fewer and less intense heatwaves across much of eastern Australia, but the intensity of heat extremes in Western Australia is Not much different between La Niña and El Niño.
The pattern of extreme heat in Western Australia and flooding in parts of Queensland is fairly typical of a La Niña summer, although temperatures over 50℃ are extremely rare.
Climate change is increasing the heat
Northern Australia has summer-average temperatures. risen as muchBecause the Top End has seen its summers get wetter than other parts of the country, it’s also been more humid. That’s in line with climate change models.
However, heat can be much more extreme when the conditions are right in Pilbara. The region is experiencing more heat events. More frequent, more intense and for a longer timeJust like in all other regions.
Most of us have chosen not to live in Australia’s hottest areas. So you might think you don’t need to worry about 50℃ heatwaves. As the climate warms, heatwave conditions will become more frequent and more severe across the continent.
In urban areas, roads and concrete soak up the sun’s heat, raising maximum temperatures by several degrees and making for dangerous conditions.
Even if we keep global warming below 2℃ in line with the Paris Agreement, we can still expect to see our first 50℃ days in Sydney and MelbourneIn the coming years. Penrith, a suburb located in Western Sydney, was very near to being completed in January 2020. Reach 48.9℃.
As you know, it’s going to be very hard to achieve even keeping global warming below 2℃, given the need to urgently slash greenhouse gas emissions in the next decade.
We already know what to do to stop this terrifying future. The stronger the action to reduce greenhouse gas emissions globally – including by major carbon emitting countries such as Australia – the less the world will warm and the less Australian heat extremes will intensify. That’s because the relationships between greenhouse gas emissions, Global temperatures Australian heat extremesThey are almost linear.
You may believe that Australians can withstand heat. But the climate you were born in doesn’t exist any more. Unfortunately, our suburbs, wildlife, and farms will not be able to withstand the heat in the coming decades.
Let’s work to make this 50℃ record an outlier – and not the new normal.