Extract from ABC News
Nearly all of Australia was warmer than normal in 2023 despite starting the year under the La Niña climate pattern, according to the Bureau of Meteorology (BOM).
Key points:
- Last year was Australia's equal eighth warmest on record
- WA had the highest temperatures and strongest rainfall deficiencies
- Australia's overall rainfall was close to average during 2023
But the country's ranking for warmth was relatively subdued in comparison to the extreme temperatures experienced around the globe in 2023, which was Earth's hottest year on record.
The bureau published its annual climate summary key points for 2023 on Friday, with a subsequent, detailed summary due in early February.
It found Australia equalled its eighth warmest year on record, with the national mean temperature just shy of 1 degree Celsius warmer than the 1961-1990 average.
"Equal eighth highest in over 110 years of record is pretty high up there," BOM climatologist Caitlin Minney said.
"I think the fact that the year is coming in in the top 10 warmest years on record for mean national temperature is something to be aware of."
WA takes title for hottest towns
All bar one of the top 10 highest temperatures in Australia in 2023 were in Western Australia, where the two highest were recorded on the final days of the year.
This included Roebourne and Marble Bar, in WA's Pilbara region, where the mercury hit 49.5C and 49.3C, respectively.
Temperatures nearing 50C are well known to the region.
In 1923 and 1924, Marble Bar earned the title of Australia's hottest town when it recorded the longest heatwave — 160 days over 37.7 degrees, which is still listed in the Guinness Book of Records.
But it was not just the Pilbara that was hot this year.
A look at the temperature anomaly's for the country shows nearly all of Australia experienced higher-than-normal temperatures in 2023.
The warmest areas, compared to normal, were spread across central WA, southern Queensland and northern New South Wales, where temperatures were on average between 1.5C and 2.5C warmer than normal for the year.
"Two to three degrees is quite significant over a whole year," Ms Minney said.
"It's definitely seeing the impacts of the El Niño this year, and especially having quite a warm winter and into spring in those areas."
The only region with lower-than-average temperature was a pocket of inland Northern Territory.
Ms Minney said a "significant factor" in the warmer temperatures, overall, was winter, which was Australia's warmest since records began in 1910.
Rain pours in deluges
Rainfall, on the other hand, was mixed across the country.
Overall, the country finished slightly above its average rainfall, but there were severe deficiencies in some states.
Western Australia's south-west corner experienced the most notable rainfall shortages, with some parts of the coast near Exmouth recording their lowest rainfall on record.
Parts of northern New South Wales and southern Queensland also finished 2023 drier than normal.
But deluges over the region from November and December helped take some of the sting out of the severe deficiencies experienced during winter and spring.
Meanwhile, northern Australia experienced higher than normal rainfall, particularly though inland Northern Territory and Cape York Peninsula.
For the Cape York Peninsula, much of this came in the final weeks of 2023 when Tropical Cyclone Jasper delivered over 2 metres of rain to some gauges in the Mossman Gorge region, and 1.9m of rainfall at the Kuranda Railway Station.
Parts of inland northern Australia were also given an unexpected boost to their annual rainfall totals in June when a unusual stream of tropical moisture dropped significant rain across the north of the country in the middle of its dry season.
Snapshot of the cities
Below is a snapshot of the highest and lowest temperatures in each of the capital cities main sites, based on BOM's weather station data for the year.
Did 2023 live up to its forecasts?
While the year started off under the influence of La Niña, attention quickly turned to the brewing El Niño in the Pacific Ocean, which was declared officially underway by Australia's BOM during September.
The climate driver is known to bring hot, dry weather to the country, particularly during spring and early summer.
Combined with the background warming of climate change, climate scientists warned Australia could be in for severe heat through spring and summer.
But Ms Minney noted they were not the only drivers at play.
"We're definitely seeing the impacts of a changing climate as well as the global ocean temperatures and the waters to the east of Australia being very warm," she said.
"And yes, there was the establishment of El Niño and the positive Indian Ocean Dipole, which were declared in early spring this year.
"There's also the Southern Annual Mode, which has been pretty consistently positive across November and December, which generally increases rainfall across eastern Australia."
Ms Minney said the warmer-than-average temperatures experienced across the country, overall, did fall in line with expectations, given those drivers at play.
"Also understanding that every climate driver event, particularly this El Niño, does behave differently," she said.
She said the average rainfall signal, overall, was not wholly unexpected either, given the year started with a La Niña climate pattern, and El Niño did not have much of an influence on rainfall during summer.
"It has been quite a year of change in terms of climate drivers," Ms Minney said.
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