A new World Meteorological Organisation (WMO) report reveals that the Indian coastal region is fast submerging compared with other parts of the world, as heat content in the Indian Ocean in the Asia region has increased since the 1990s and reached a new record in 2025.
According to the WMO State of the Climate in Asia 2025 report, Sea level in the Asia region reached its highest level since satellite records began in 1999.
The rates of sea-level rise from 1999-2025 along much of the northern Indian Ocean coast exceeded the global average of approximately 3.6 mm per year, reaching around 4.9 mm per year along the Indian coast and more than 6 mm per year in the Kuroshio Current region.
As a result of the record increase in ocean heat, marine heat wave frequency has also risen in Asia. Marine heatwaves affected almost the entire ocean area of Asia, with over 10 million km2 impacted during July–September, more than the size of the People’s Republic of China or the United States of America.
Continued ocean warming and acidification pose increasing risks to marine ecosystems and coastal communities.
Further, rising temperatures in the region result in mass loss across all 23 monitored glaciers. The melting of glaciers threatens long-term water security in the world’s most heavily populated region and leads to an increase in hazards – with multiple glacial lake outburst floods and glacier collapses recorded in 2025.
The melting of glaciers affects sea level, regional water cycles and the occurrence of local hazards such as glacial lake outburst floods.
Not only the ocean temperature, but overall Asia has also warmed faster than the global average in recent decades, with the warming trend during 1991–2025 approximately twice that observed during 1961–1990. The year 2025 was between the second and fourth warmest year on record depending on the dataset used.
The annual mean temperature over Asia in 2025 was 0.96 °C + 0.08 above the 1991–2020 average and ranked between the second and fourth warmest year on record, depending on the dataset used.
The report highlights the significant impact of too much or too little rainfall.
Most of southern Asia received above-average precipitation in 2025, with the monsoon delivering exceptionally heavy rainfall. In Pakistan, monsoon flooding was associated with more than 1,000 deaths and left over 3 million people requiring assistance.
The report highlights the growing importance of impact-based forecasting and early action. Tropical Cyclone Ditwah brought extreme rainfall to Sri Lanka, with approximately 10% of the typical annual rainfall total falling within 24 hours. The event resulted in more than 640 deaths, displaced over 200,000 people and with economic losses estimated at around 4% of GDP.
In China, heavy rainfall in Liangshan, Sichuan Province, demonstrated the value of timely warnings and coordinated action. Early evacuation helped reduce disaster impacts and save lives.
“Asia is impacted by rising temperatures, warming ocean waters, higher sea levels and retreating glaciers. The importance of observations, early warning systems and impact-based forecasting to adapt to our changing climate,” said WMO Secretary-General Celeste Saulo.
