January 2025 marked the hottest month on record, with global temperatures reaching 1.7°C above pre-industrial levels. Despite expectations that the natural La Niña phase of the El Niño–Southern Oscillation would bring slight cooling, the record heat indicates that human-driven ocean warming is overwhelming natural climate fluctuations. Typically, La Niña cools global temperatures by a few tenths of a degree, but this cycle proved too weak as surrounding ocean waters remained unusually warm. The diminished cooling effect is exacerbated by rising greenhouse gas levels and reduced aerosol pollution, which previously helped reflect sunlight. With major regions across Europe, Africa, and beyond experiencing above-average temperatures, the unprecedented heat of January underscores that natural cooling phases may no longer offset global warming. This alarming trend highlights the urgent need for significant emissions reductions and a shift toward more sustainable practices.
Source: The Conversation