La Niña fails to cool planet as 2025 ranks among warmest years: WMO

The World Meteorological Organization (WMO) on Wednesday confirmed.

That 2025 ranked among the three warmest years ever recorded, underlining the persistence of exceptional global temperatures driven by climate change.

After analysing eight major international climate datasets, the UN-backed agency said the global average surface temperature in 2025 was around 1.44°C above pre-industrial levels (1850–1900). Two datasets ranked 2025 as the second warmest year in the 176-year global temperature record, while the remaining six placed it third, indicating strong scientific consensus.

Warm year despite La Niña

Unusually, 2025 recorded such high temperatures despite the influence of La Niña, a climate pattern that typically brings cooler global conditions. The WMO said the year was slightly cooler than the 2023–25 three-year average, partly due to La Niña’s moderating effect.

However, the organisation stressed that this short-term cooling failed to offset the long-term warming trend.

“The year 2025 started and ended with a cooling La Niña and yet it was still one of the warmest years on record globally because of the accumulation of heat-trapping greenhouse gases in our atmosphere,” WMO Secretary-General Celeste Saulo said.

Extreme weather intensified

According to the WMO, persistently high land and ocean temperatures in 2025 fuelled an increase in extreme weather events worldwide, including prolonged heatwaves, intense rainfall, floods and deadly tropical cyclones. The agency said the trend reinforced the need for stronger early-warning systems and improved climate preparedness.

Oceans continue to absorb heat

The WMO also warned that ocean temperatures last year were among the highest ever recorded, reflecting the long-term accumulation of heat in the world’s oceans, a key regulator of Earth’s climate.

Around 33 per cent of the global ocean area experienced conditions ranking among their three warmest years since records began in 1958, while nearly 57 per cent fell within their top five warmest. Affected regions included the tropical and South Atlantic, the Mediterranean Sea, the North Indian Ocean, and the Southern Ocean.

Detailed report due in March

The WMO said its full findings—covering greenhouse gas concentrations, surface temperatures, ocean heat content and long-term climate trends—will be published in the State of the Global Climate 2025 report, scheduled for release in March.

The latest assessment adds to growing evidence that global warming is continuing unabated, even in years when natural climate patterns such as La Niña would normally bring temporary cooling.