What is causing the extreme warming in the North Pacific?

The article suggests that changes to shipping fuels and efforts to reduce air pollution in China may be contributing factors, as they have reduced the cooling effect of atmospheric particles.

How could the North Pacific heatwave affect the UK's weather?

The article states that the unusual warming in the "warm blob" may have the opposite effect in the UK, potentially leading to a colder start to winter.

What is the La Niña weather pattern, and how might it interact with the North Pacific heatwave?

The article explains that La Niña, a natural weather pattern, is expected to persist in the coming months, which generally increases the risk of a cold start to winter in the UK, but also brings a higher chance of a mild end.

Home / Weather / Mysterious North Pacific Heatwave Shatters Temperature Records

Mysterious North Pacific Heatwave Shatters Temperature Records

18 Oct, 2025

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Summary

North Pacific sees warmest summer on record in 2025
Temperatures over 0.25°C above previous high, across vast area
Unusual warming may impact UK weather, potentially leading to colder winters

Mysterious North Pacific Heatwave Shatters Temperature Records

In 2025, the north Pacific has seen its warmest summer on record, according to a BBC analysis of the region's mysterious marine heatwave. Sea surface temperatures between July and September were more than 0.25°C above the previous high, across an area roughly ten times the size of the Mediterranean.

While climate change is known to make marine heatwaves more likely, scientists are puzzled by the scale and duration of the current event. Some researchers believe the unusual warming in the so-called "warm blob" may have the opposite effect in the UK, potentially leading to a colder start to winter.

"There's definitely something unusual going on in the north Pacific," said Zeke Hausfather, a climate scientist at Berkeley Earth. The jump in temperatures across such a large region is "quite remarkable," he added.