SINGAPORE - Unprecedented heat waves in the Southwest Pacific affected more than 10 percent of the global ocean surface in 2024, damaging coral reefs and putting the region's last remaining tropical glacier at risk of extinction, the UN's weather body said on Thursday.

Average 2024 temperatures in the region - which covers Australia and New Zealand as well as southeast Asian island states like Indonesia and the Philippines - were nearly half a degree Celsius (0.9 Fahrenheit) higher than the 1991-2020 mean, the World Meteorological Organization said in an annual report.

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"Much of the region saw at least severe marine heat wave conditions at some point during the course of 2024, particularly in areas near and south of the equator," said the WMO's Blair Trewin, one of the report's authors.

Extreme heat over the year affected 40 million square kilometers (15.4 million square miles) of ocean, and new temperature highs were set in the Philippines and Australia, the report said. Ocean surface temperatures also broke records, while total ocean heat content was the second-highest annual average, behind 2022.

An unprecedented number of cyclones, which experts have attributed to climate change, also caused havoc in the Philippines in October and November.

Sea levels continue to rise more quickly than the global average, an urgent problem in a region where more than half the population live within 500 meters (547 yards) of the coast, the report added.

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The report also cited satellite data showing that the region's sole tropical glacier, located in Indonesia on the western part of the island of New Guinea, shrank by up to 50 percent last year.

"Unfortunately, if this rate of loss continues, this glacier could be gone by 2026 or shortly thereafter," said the WMO's Thea Turkington, another of the report's authors.

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