Lack of data about conditions in the Russian Arctic is already hampering climate science, and will cause ever-growing gaps in our understanding of how climate change affects the fastest-warming region of the planet, scientists warn.

The Arctic is warming up to four times faster than the Earth as a whole. And Russia has more Arctic land than any other nation. But, since Russia invaded Ukraine, it's been increasingly difficult for climate scientists in Russia to collaborate or share data about conditions in the country's vast frozen areas.

That includes basic measurements of temperature and snowfall in the Russian Arctic, as well as more sophisticated details about greenhouse gas emissions and what's happening to plants and animals in the region.

Excluding such data from climate models makes them less accurate, and the problem will get worse over time, a new study warns. "By neglecting Russian sites, we decrease our chances to mitigate the negative consequences of climate change," says Efrén López-Blanco of Aarhus University in Denmark, who is one of the authors of the paper, published in the journal Nature Climate Change.

In order to build climate models that can accurately predict what will happen to the Arctic in the future, scientists need measurements from across the Arctic. If the available data is concentrated in a few places, like Alaska, Canada and Scandinavia, and excludes Russia's vast Arctic expanses, then the models will be increasingly inaccurate, the study finds.

"It's a huge landmass," says Ken Tape, an ecologist at the University of Alaska Fairbanks. "You can't ignore it."

Beaver access has been cut off for western scientists

Tape is already seeing the negative effects of the war on his area of research. He studies beavers, which are moving into the tundra and are often unpopular neighbors.

"It's like an intruder," he says. "The connotations are not positive, you know? Especially if fish is a big resource for you, you're going to be very skeptical of someone who comes in and dams up fish-bearing streams."

Scientists like Tape are studying where beavers are showing up, and trying to understand how far North the population will move, how quickly and at what scale. Such research can help local communities manage the animals: beavers are notorious for turning streams into bogs, for example, which can affect water quality for humans nearby.

The research is also important because when beavers build dams, they can disturb frozen ground, which can release trapped greenhouse gasses as it thaws.

A few years ago, Tape helped start the Arctic Beaver Observation Network, so scientists all around the Arctic could collaborate and share data. But with the invasion of Ukraine, the dream of Russian collaboration in the project stalled, he says. "We're having a meeting at the end of February," he says, "and it's basically Alaska, Canada and Scandinavia. There's no one from Russia coming."

On top of that, western scientists no longer have access to field sites in Russia, he says. Instead, they have to rely on what they can see from space, from satellite images of beaver dams. "You can do a lot from space, but you need to have some boots on the ground confirming what you're seeing," Tape explains.

For some, it's a reminder of Cold War science

For Russian climate scientists who started their careers in the Soviet Union, the current situation can feel eerily familiar.

"In the past – like, Soviet Union past – the data from this part of the world was also limited," says Vladimir Romanovsky, a permafrost expert at the University of Alaska Fairbanks who trained in Moscow. In the mid-1970s, young scientists had virtually no contact with western collaborators, he remembers.

But when things opened up in the 1990s, he says, his field exploded. "During that time, lots of data became available from the Russian permafrost regions," he remembers. International scientists started collaborating with Russian scientists to investigate how permafrost was changing.

And the research findings were explosive. Permafrost is the permanently frozen ground found across the Arctic. As it thaws, it creates massive problems for infrastructure built on top of it, causing roads to buckle, building foundations to crack and pipelines to break.

It can also release enormous amounts of planet-warming gasses that are trapped within the frozen earth. Scientists now warn that virtually all surface permafrost could be gone from the Arctic by the end of the century.

But now the data that is so crucial for permafrost science is drying up, Romanovsky says.

In the past, he and other western scientists received temperature and soil measurements from Russian research facilities. "This year, there may not be any data," he says. "If this will continue into the future, eventually it may have some impact on our understanding [of permafrost changes.]"

Romanovsky is also concerned about young Russian scientists who are important to the future of climate research in the region. "It's very discouraging," he says. "Eventually, I believe that we will be able to communicate openly again."