'Deadly and destructive': Australia's nearest glaciers are about to vanish

In a little over two years the total ice area on the Sudirman Range north of Australia - home to the highest island peak in the world - shrank by up to 50 per cent.

"If this rate persists, total ice loss is expected in 2026 or very soon thereafter," the World Meteorological Organisation (WMO) revealed in its 2024 State of the Climate in the South-West Pacific report.

Released on June 5 - World Environment Day - the climate report card confirmed 2024 was the warmest on record for the region, punctuated by record-breaking rain, temperatures and marine heat waves.

From Australia's hottest-ever summer temperature recorded at 49.9°C in Western Australia's Carnarvon to 315mm of rainfall over just four days in the Northern Territory, 2024 was a year of extremes.

It was also the first year to top the critical 1.5 degrees of warming above pre-industrial levels, though an individual year with that temperature rise is not alone enough to declare Earth has passed the threshold.

"It's absolutely true that we're already starting to see individual years with global temperatures more than 1.5 degrees above pre-industrial [levels]; 2024 was likely the first of those," one of the report's lead authors, Dr Blair Trewin, said.

"It's clear that we're getting quite close to warming at that 1.5 degree level," he said.

"At current warming trends that level will be reached within the next five to 10 years."

Flooding on the scale seen across the NSW mid north coast and Hunter region in May - which claimed five lives, left 800 homes uninhabitable and stranded tens of thousands of people - was likely to continue.

WMO regional director Ben Churchill said this was because a warmer atmosphere held more moisture.

"For every one degree of warming in the atmosphere the atmosphere can hold an extra seven per cent of moisture," he said.

"And so we're seeing these extreme situations both in terms of rainfall, but also on the other end of the scale - we're seeing extreme drought."

The report identified the southern coast of Australia as particularly hard hit by low rainfall.

"Global warming is actually changing the water cycle quite significantly," Mr Churchill said.

But unprecedented marine heatwaves were also a feature of 2024, affecting nearly 40 million square kilometres of ocean - the largest area since 1993.

Severe hotspots were recorded off Australia's east coast and southern parts of the Tasman Sea.

"Averaged over the region as a whole, sea surface temperatures reached record highs in 2024 by a substantial margin," Dr Blair Trewin said.

"That has significant implications for marine ecosystems and, in particular, corals which are very sensitive to excess heat were quite significantly stressed by the marine heat waves in various parts of the region."

The World Heritage-listed Great Barrier Reef suffered widespread and severe coral bleaching in 2024.

"We have seen some quite significant impacts of marine heatwaves on fisheries in Tasmania, for example," he said.

Ocean warming helps sea levels rise and changes ocean currents, storm paths and marine ecosystems.

And the sea is rising faster around Australia than in other parts of the world.

"Sea level is rising, in general, faster in this region over the last 30 years [than] the global average," Dr Trewin said.

"That increase in sea level has been reflected by an increase in the frequency of coastal flooding and inundation."

Warming temperatures were also affecting Australia's snow seasons, which were ending earlier than in the past.

Spencers Creek near Perisher Valley in NSW reached a peak depth of 1.23 metres in late July 2024 - 35 per cent below average.

WMO regional director Ben Churchill said the latest climate snapshot was another wake up call.

"We keep talking about things that we've never seen before, and this just continues that trend," he said.

"Widespread extreme rainfall and flooding caused deadly and destructive impacts in Australia, New Zealand, and also countries in the Pacific, and also in south-east Asia," Mr Churchill said.

"This has been driven by carbon emissions which are continuing unabated, so this is a message for stronger climate action, not just in this region, but globally.

"It's an alarming report, but it is really - again - a wake-up call for stronger climate action."

The World Meteorological Organisation is the United Nations' agency for weather, climate and water.

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