World Has Record Hot January Despite Outlook for La Niña Cooling

(Bloomberg) -- Last month was the hottest January on record, with global average temperatures climbing 1.75C above pre-industrial levels.

The temperature in January averaged 13.2C (55.8F), according to preliminary data from the European Centre for Medium-Range Weather Forecasts, a UK-based research institute supported by 35 states. The ECMWF data was published by the Climate Change Institute at the University of Maine.

In a post detailing the new data, climate scientist Zeke Hausfather said he was surprised to see another all-time high, given expectations that La Niña would make 2025 cooler than a record-hot 2024. “This means that January 2025 stands out as anomalous, even by the standards of the last two years,” he wrote.

After back-to-back record years in 2023 and 2024, the world has been holding onto heat even as the new year began. December was the second-warmest on record, both on land and in the ocean, the US National Centers for Environmental Information said. Despite a weak La Niña cooling the equatorial Pacific from that month, records are being set in the Caribbean Sea, as well the Indian Ocean and other parts of the Pacific. 

Record warm temperatures covered 6.6% of the world’s surface in December, the agency said.

If the record is confirmed, it bolsters research showing warming across the planet is not just increasing, it’s accelerating. 

New research led by James Hansen, director of the climate program at Columbia University and the former NASA scientist who first brought the concept of climate change to the attention of Congress in the 1980s, suggests governments have underestimated how much warming is accelerating. That in turn is magnifying natural climate cycles and intensifying extreme weather events.

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