Parts of the Arctic were an average of 11 degrees Celsius warmer than they were in the late 20th century as the region experienced “extreme record temperature anomalies”, the US National Oceanic and Atmospheric Administration (NOAA) has said.
Scientists who produced the annual Arctic Report Card warned the situation was changing so quickly it was “outpacing our ability to understand and explain” what they were witnessing.
They even suggested the word glacial could no longer be used to mean a slow pace and should be redefined to refer to something that was “rapidly diminishing”.
The report found the average annual air temperature over land areas was the “highest in the observational record” at 3.5C above 1900. Sea ice levels also fell to the lowest since satellite records began in 1979.
These are both likely to indicate the warmest Arctic weather for tens of thousands of years.
The Arctic has a considerable effect on the northern hemisphere’s weather with some experts saying the rapid warming of the region – more than twice the global average – could produce “catastrophic” extreme weather events for much of the planet.
As climate science denier Donald Trump prepares to move into the White House next month, the NOAA report said the situation was “increasing the pressure” to communicate the importance of the “scientific observations”.
Jeremy Mathis, director of NOAA’s Arctic research programme, said: “Rarely have we seen the Arctic show a clearer, stronger or more pronounced signal of persistent warming and its cascading effects on the environment than this year.
“While the science is becoming clearer, we need to improve and extend sustained observations of the Arctic that can inform sound decisions on environmental health and food security as well as emerging opportunities for commerce.”
“Arctic temperatures continue to increase at double the rate of the global temperature increase,” it added.
Amid the 3.5C increase on land, there were some particularly “extreme record warm temperature anomalies”.
“The warmest temperature anomalies were centred on Alaska, Svalbard in the Atlantic sector and the central Arctic,” the report said.
“In the Spitsbergen area, the three-month winter mean temperatures were 8 to 11C above the 1961-90 average.”
The levels of ice on both land and sea have been shrinking dramatically.
“For Arctic researchers, communicating the impacts of our discoveries has taken on an unprecedented urgency in the face of environmental change that – in many instances – is outpacing our ability to understand and explain the changes we are witnessing,” the report said.
“Accustomed to advancing our scientific disciplines at what is often called a ‘glacial’ pace, we recognise that glaciers are not so slow anymore.
“Before long, we may need to redefine ‘glacial’ to mean something that is rapidly diminishing or employ a different adjective.”
Sea ice grows and shrinks with the seasons hitting a low point in October or November. This year the sea ice minimum was the lowest since satellite records began in 1979.
Scientists expect the Arctic to be effectively free of sea ice for the first time in about 100,000 years within the next few decades, but some have argued this could happen much sooner.
“Sea ice extent has decreasing trends in all months and virtually all regions, the exception being the Bering Sea during winter,” the NOAA report said.
It said the changes in the Arctic could lead to a number of “trillion dollar impacts – both positive and negative”.
On one hand, new shipping lanes are already opening up and, ironically, less ice also means oil exploration is not as risky.
But, on the other, the warming Arctic could have “major implications” for our economic welfare and life as we know it, the report said.
“As is amply demonstrated in each annual instalment of the Arctic Report Card, the domain is collectively experiencing rapid and amplified signatures of global climate change,” it said.
“The Arctic system’s response to this broader forcing has become a central research topic, given its potential as a critical throttle on future planetary dynamics.
“Changes are already impacting life systems, cultures and economic prosperity and continued change is expected to bear major implications far outside the region.”
Professor Peter Wadhams, the head of the Polar Ocean Physics Group at Cambridge University and author of the book, A Farewell to Ice, warned the loss of snow cover, which has hit a record low, and sea ice was speeding up global warming.
"I calculate that between them they are causing the effective heating of the planet to be 50 per cent higher than would be caused by the added greenhouse gases alone – entirely due to snow and ice retreat," he told the Independent in an email.
Professor Wadhams suggested that Arctic sea ice was "well and truly set on a collapse".
And this, he warned, could have a dramatic and sudden effect on global temperatures.
"The warm sea water melts the offshore permafrost, which releases methane trapped in the sediments below," Professor Wadhams said.
"There is potential for a catastrophic methane pulse which cause immediate warming of up to 0.6C, according some calculations which we did in [the journal] Nature a couple of years back."
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies