Areas of the Canadian Arctic permafrost are thawing rapidly, 70 years ahead of when scientists previously believed, as the climate crisis continues to push the planet towards dangerous tipping points.

Reuters reported on the change Tuesday citing the June 10 research of University of Alaska Fairbanks scientists like geophysics professor Vladimir E. Romanovsky. In an interview, Romanovsky told the news agency that the change in the Arctic permafrost was “amazing” to witness and “an indication that the climate is now warmer than at any time in the last 5,000 or more years.”

Melting permafrost could release potentially catastrophic levels of methane and other gases trapped for millennia into the atmosphere, adding to a feedback loop that could accelerate the climate crisis and lead to more warming. As Common Dreams reported in April, the permafrost is already emitting more gasses than previously thought; the new research indicates that this is part of a larger issue.

The scientists found the change as they visited the Arctic region. According to Reuters:

Diving through a lucky break in the clouds, Romanovsky and his colleagues said they were confronted with a landscape that was unrecognizable from the pristine Arctic terrain they had encountered during initial visits a decade or so earlier. The vista had dissolved into an undulating sea of hummocks—waist-high depressions and ponds known as thermokarst. Vegetation, once sparse, had begun to flourish in the shelter provided from the constant wind.

Jennifer Morgan, executive director of Greenpeace International, characterized the rapidly thawing permafrost as “one of the tipping points for climate breakdown” that is “happening before our very eyes,” and another “clear signal that we must decarbonize our economies” without further delay.

One of Romanovsky’s co-authors described the melting permafrost as the “canary in the coal mine.”

“It’s very likely that this phenomenon is affecting a much more extensive region and that’s what we’re going to look at next,” said researcher Louise Farquharson.