August 2024 temperature record in Svalbard exceeds climate warming trend

A record-high monthly mean temperature of 11.0°C was measured in August 2024 in Longyearbyen, the capital of the Svalbard Archipelago, located more than a thousand kilometers north of the Arctic Circle.

Not only was this a striking 2.6°C warmer than the previous record for August mean temperature set just a year earlier, but it was also 1.0°C above the record for July – traditionally the warmest month in Svalbard. This made August 2024 the warmest month since the start of the records in 1899. The summer (June, July, August) of 2024 also was the warmest on record, and the margin by which the record was broken was itself record-breaking.

To study the extremity of these records, the long-term warming trend was removed from the August and summer temperature observations in Longyearbyen. From this followed that even though the summer temperature exceeded previous records by an extreme margin, the value fits within the expected range of temperature observations. The August temperature fell, however, far outside of previously observed temperature variability – even after accounting for climate change. The research was published in Geophysical Research Letters.

Extreme temperatures were caused by southerly winds and warm sea surfaces

It is generally recognized that Svalbard is one of the fastest warming places on Earth. But what brings additional interest to these records, is the fact that traditionally the most extreme temperature increases have been observed in wintertime, not in summer. Therefore, the causes behind these temperature extremes were also examined.

The research revealed that the extreme temperatures were caused by an unprecedented combination of persistent, southerly winds over the Svalbard and Barents Sea region and extremely warm sea surface temperatures around the Archipelago. Together, these factors enabled efficient transport of warm air to Svalbard.

Summer temperatures strongly affect the Arctic environment

Summer temperatures play a major role in Arctic environment, as it strongly affects the ecology in the region. Extremely high summer temperatures are also one of the dominant drivers in glacier and permafrost melt.

It is not yet clear whether this kind of persistent weather patterns in the Svalbard and Barents Sea region will become more common in the future. It is however likely, that sea surface temperatures in the area will keep rising. This means that such temperature extremes may also become more common, with large impacts on the local environment.

The research was a combined effort between the Polar Meteorology and Climate Group and the Extreme Weather and Climate Change Group of the Finnish Meteorological Institute.

Further information

Researcher Daan van den Broek, Finnish Meteorological Institute, daan.van.den.broek@fmi.fi

Scientific article is available in Geophysical Research Letters.

Reference: van den Broek, D., Urbancic, G. H., Rantanen, M., & Vihma, T. (2025). Svalbard's Record-Breaking Arctic Summer 2024: Anomalies Beyond Climatological Warming Trends. Geophysical Research Letters, 52(8), https://doi.org/10.1029/2025GL115015.