During a winter field mission in February 2025, an international team of researchers was confronted with above-freezing temperatures, persistent rainfall, and widespread melting across the Svalbard archipelago. An anomaly that has become routine in an Arctic where winter, once reliably harsh, is giving way to an unstable and worrying climate regime.
At 78° north latitude, in the heart of February, scientists waded through meltwater at the foot of a glacier. The scene could be mistaken for a fever dream. Yet it was all too real. “Standing in pools of water at the snout of the glacier, or on bare, green tundra, was shocking and surreal,” said James Bradley, Reader in Environmental Science at Queen Mary University of London, in a press release published by the university. His team, there to study freshly fallen snow, was able to collect it only once in two weeks of fieldwork. In a commentary published on July 21 in Nature Communications, the scientists reported striking observations.
Svalbard, a Norwegian archipelago located a thousand kilometers from the North Pole, is warming at a rate six to seven times higher than the global average. In winter, this amplification is even more pronounced. In February 2025, temperatures in Ny-Ålesund, one of the northernmost inhabited places on Earth, averaged -3.3 °C, compared to a historical average of -15 °C (1961–2001). Fourteen days of the month recorded temperatures above 0 °C, a critical threshold which, once crossed, fundamentally alters Arctic ecosystems.
Sampling with a spoon
The researchers describe a landscape turned into a “melting ice rink“. The soil, normally frozen solid, had thawed enough to be sampled with a spoon. Vegetation, awakened by the unusual warmth, was emerging through the melting snow. “[…] we witnessed premature plant emergence and thawing of surface soils,” they observed, underscoring the disruption of seasonal timing.
This early thaw, aggravated by rainfall events, is altering the soil at depth. Water pooling in the frozen ground’s pores refreezes into dense ice crusts. These crusts hinder gas exchange between the soil and atmosphere, promote methane production, and deprive reindeer of their winter forage. Such processes create feedback loops: the warmer the soil, the more microbial activity increases, accelerating organic matter breakdown and the release of greenhouse gases.
“Irreversible changes to the Arctic climate are happening in front of our own eyes,” warns Donato Giovannelli, geomicrobiologist at the University of Naples Federico II and co-author of the study. The impact is systemic: hydrology, permafrost dynamics, infrastructure stability, travel safety, and species survival are all affected simultaneously.
On the ground, the consequences are immediate. Snowmobiles get bogged down in slushy snow. Research plans must be adjusted. The risk posed by polar bears does not diminish, but options for a rapid retreat to the safety of research stations are reduced. “The gear I packed felt like a relic from another climate,” says Bradley.
‘This is the new Arctic’
The researchers are calling for a shift in perspective. Long seen as a silent season, unsuitable for expeditions and poorly documented, Arctic winter is becoming a key period in the unfolding climate upheaval. And yet, data remains scarce. The Nature Communications commentary calls for increased winter fieldwork, enhanced permafrost monitoring, and a move toward anticipatory policymaking. “Climate policy must catch up to the reality that the Arctic is changing much faster than expected, and winter is at the heart of that shift ,” insists Dr Bradley.
Far from an isolated event, the winter of 2025 appears to mark a new baseline. “These winter warming events are seen by many as anomalies, but this is the new Arctic,” the authors conclude. In Ny-Ålesund and beyond, what was once temporary is becoming structural, disrupting the very logic of polar seasons.