Senior government climatologist Simon Grainger said the rolling 12-month period between April 2024 and March 2025 was 1.61 degrees Celsius (34.9 degrees Fahrenheit) above average -- the hottest since records began more than a century ago.

"This is certainly part of a sustained global pattern," he told AFP.

"We've been seeing temperatures since about April 2023 that were globally much warmer than anything we have seen in the global historical record."

The previous hottest period was in 2019, Grainger said, when temperatures were 1.51 degrees Celsius above average.

"That is a pretty significant difference," Grainger said.

"It's well above what we would expect just from uncertainties due to rounding. The difference is much larger than that."

The record was measured on a rolling 12-month basis -- rather than as a calendar year.

Australia has also recorded its hottest-ever March, Grainger said, with temperatures more than two degrees above what would normally be seen.

"There has basically been sustained warmth through pretty much all of Australia," he said.

"We saw a lot of heatwave conditions, particularly in Western Australia. And we didn't really see many periods of cool weather -- we didn't see many cold fronts come through."

- Sickly white coral -

From the arid outback to the tropical coast, swaths of Australia have been pummelled by wild weather in recent months.

Unusually warm waters in the Coral Sea stoked a tropical cyclone that pummelled densely populated seaside hamlets on the country's eastern coast in March.

Whole herds of cattle have drowned in vast inland floods still flowing across outback Queensland.

And a celebrated coral reef off Western Australia has turned a sickly shade of white as hotter seas fuel an unfolding mass bleaching event.

The average sea surface temperature around Australia was the "highest on record" in 2024, according to a recent study by Australian National University.

This record run looked to have continued throughout January and February, said Grainger.

"We haven't seen much cooling in sea surface temperatures."

Moisture collects in the atmosphere as oceans evaporate in hotter temperatures -- eventually leading to more intense downpours and storms.

Australia follows a slew of heat records that have been toppling across the planet.

Six major international datasets confirmed that 2024 was the hottest year on record.

Scientists are unanimous that burning fossil fuels has largely driven long-term global warming.

Australia sits on bulging deposits of coal, gas, metals and minerals, with mining and fossil fuels stoking decades of near-unbroken economic growth.

But it is increasingly suffering from more intense heatwaves, bushfires and drought, which scientists have linked to climate change.