This is according to the US National Oceanic and Atmospheric Administration's Arctic Report Card.
Director of the administration's Arctic Researcher Program, Dr Jeremy Mathis, said the region did a great service to the planet - acting as a refrigerator.
"We've now left that refrigerator door open," he added.
Dr Mathis was speaking at the annual American Geophysical Union meeting in New Orleans, where Noaa presented its annual summation of Arctic science.
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This is the 12th report the administration has produced. And although it pointed to "a few anomalies" in a recent pattern of warming in the Arctic region, Dr Mathis said: "We can confirm, it will not stay in its reliably frozen state."
"The thing I took that had the most resonance for me was we're able to use some really long-term records to put the Arctic change into context - going back more than 1,500 years.
"What's really alarming for me is that we're seeing the Arctic is changing faster than at any rate in recorded history."
The speed of change, Dr Mathis added, was making it very hard for people to adapt.
"Villages are being washed away, particularly in the North American Arctic - creating some of the first climate refugees," he said.
"And pace of sea level rise is increasing because the Arctic is warming faster than we anticipated even a decade ago."
Scientists say it is clear that human-induced climate change is contributing to making the Arctic a warmer and more dynamic place.
"When we look at the darkening of the Arctic," said Dr Mathis, "reflective, icy surfaces are melting to reveal darker surfaces that absorb more of the Sun's energy.
"So it probably only took a little bit of human-induced change to start the Arctic down this cascading pathway; a little bit of ice melting led to a little bit of warming, which led to more ice melting, which led to more warming.
"And now we're seeing an acceleration - a runaway effect that may eventually be a catastrophic runaway effect starting to take hold in the Arctic."
Oceanographer and retired US Navy Rear Admiral Timothy Gallaudet, who was appointed by the Trump Administration as acting administrator of Noaa, was asked during the Arctic report presentation about the response of the White House to the findings.
Many scientists viewed President Trump's recent decision to withdraw the US from the Paris Climate Agreement as clear evidence of his scepticism about human-induced climate change.
He said that the White House was "addressing and acknowledging it and factoring it in to their agenda".
Dr Mathis added that information coming from this report was "beyond reproach".
"They're facts. Facts weighted in thousands and thousands of scientific measurements that have been validated and peer reviewed by a community of experts working in the area for decades.