Ocean warming, rising seas threaten South-West Pacific, WMO warns

The World Meteorological Organization (WMO) warned Tuesday that warming oceans, rising sea levels and increasingly frequent marine heat waves are posing growing risks to livelihoods, ecosystems and vulnerable coastal communities across the South-West Pacific as the region recorded its second warmest year on record in 2025.

In its latest State of the Climate in the South-West Pacific report, the UN weather agency said 2025 was the region’s second warmest year since records began, behind only 2024, with extreme weather causing widespread economic losses and loss of life.

“For many countries and territories in the South-West Pacific, the ocean is central to livelihoods, economies and resilience,” WMO Secretary-General Celeste Saulo said in a statement.

She said the region experienced warming oceans, rising sea levels, marine heat waves, ocean acidification, tropical cyclones and continued tropical glacier loss during the year.

The report said marine heat waves affected almost the entire South-West Pacific in 2025, making it the most extensive year on record without an El Nino event. It warned that this was particularly concerning as a potentially strong El Nino is now developing, raising the prospect of even more widespread marine heat waves in 2026.

According to the report, record ocean heat content was observed south of Australia, in the southern Tasman Sea and parts of the tropical North Pacific, contributing to widespread coral bleaching, fish deaths and disruptions to fisheries and aquaculture.

The report also warned that Indonesia’s last remaining tropical glacier had shrunk to about 2% of its 1988 extent and is expected to disappear by the end of 2026 or early 2027.

Sea levels across the region rose by an average of 3.7 millimeters (0.14 inches) per year between 1999 and 2025, threatening low-lying island nations and coastal communities.

The deadliest weather event of the year was Cyclone Senyar, the first known tropical cyclone to reach cyclone intensity in the Strait of Malacca. It affected more than 10 million people in Indonesia and Malaysia and killed more than 1,200.

The report said early warnings and local coordination helped reduce casualties during the storm but highlighted persistent gaps in last-mile warning delivery, particularly for coastal communities and fishers.

“Early warning and early action save lives when alerts are timely, messages are trusted and last-mile delivery reaches the vulnerable,” said Armida Salsiah Alisjahbana, executive secretary of the UN Economic and Social Commission for Asia and the Pacific.

ANEWS wp:paragraph