Temperatures in some areas of the Arctic were six degrees or more above average in February.
It is difficult to predict with certainty how quickly climate change will transform our planet’s north polar region. But researchers are already seeing the ice retreat rapidly. And models predict ice-free Arctic summers to come.
Fifth hottest February on record
Data from the Copernicus Climate Change Service show that globally, February 2023 was the fifth warmest on record, with temperatures 0.3° Celsius above the 1991-2020 average.
If we look at the map of temperature anomalies around the world, we can see some prominent features.
First, in northern Canada and parts of the western United States, temperatures were several degrees below average:
In Europe, in general, it was warmer: February temperatures were 1.2° Celsius above the average for the month:
And then, in deep red, above Norway and Russia, temperatures were six degrees or more above average in February.
And those higher temperatures in the Arctic last month come at a time of year when sea ice should be plentiful in late winter.
Sea ice extent was at its second lowest level on record in February, and sea ice concentration was below average in areas shaded red on the map around Western Siberia and Svalbard.
The Arctic is warming much faster than the global average
At the Norwegian Polar Institute in Tromsø, located inside the Arctic Circle, researchers study the impact of climate change on the region.
The Arctic is warming three to four times faster than the global average, and sea ice scientist Mats Granskog has witnessed the changes with his own eyes.
“When I first went out about 20 years ago, there was a lot of thick, heavy ice,” he explains. “Today, in some years, we have difficulty finding a piece of ice, a block of ice to work with. So, a lot has changed in the last few decades.”
Every year, scientists sail to northeast Greenland to collect samples on their way to the North Pole and then bring them back to Tromsø for study.
The ice is getting thinner
Arctic sea ice cores are stored at -24° in the freezer, so special thermal protection equipment is needed to examine them. Each ice core represents a snapshot of the Arctic at the time the samples were collected.
“This was taken at the end of July last summer, when we reached the North Pole”, says Mats. “Last summer there was about 1.5 meters of sea ice at the North Pole. It was normal to have about 3 meters of ice 20 years ago.”
In the ice lab next door, Dimitry Divine studies how ice came to be. The main changes he observes relate to the age and thickness of the ice.
There is something called first-year ice and multiyear ice. The Arctic tends to have a mixture of both, but the central Arctic and areas north of Canada tend to have more multi-year ice. But as it warms, the oldest ice is disappearing. We do not use the term “young ice” as it is scientifically distinct from “first year ice”.
“The ice is getting thinner,” he explains. “It won’t be able to survive the summer thaw.”
Older types of ice are disappearing
It also affects the overall ice age. The researchers distinguish between first-year ice and multiyear ice. The Arctic tends to have a mixture of both, but the central Arctic and areas north of Canada tend to have more multi-year ice. But as it warms, the oldest ice is disappearing.
“Most Arctic ice is now dominated by first-year ice forms,” explains Dimitry. The oldest types of ice, which would have predominated 20 to 30 years ago in the central Arctic, have all but disappeared.”
“We see, especially in the western Arctic, increasing amounts of snow and ice precipitation over the last decade,” he adds. “And this is related to a warmer and wetter Arctic in general.”
Warming in the Arctic is due in part to what are known as feedback loops: for example, open ocean water is darker than ice, so it heats up faster and accelerates melting.
However, there are still many things we have not mastered about this polar region.
“Sea ice depends on the atmosphere and the ocean below. And it’s quite a complex system to understand. And I think the big questions are what will the Arctic look like in the future? how it works today”, says Mats.
“Forecasts or our climate models tell us that there will certainly come a time when we can consider the Arctic ice-free in the summer. But we don’t know exactly when that will happen and we don’t know all the reactions of the system. And I don’t think we know if it will just be gradual or we’re going to have some kind of abrupt shift that puts the system in a whole new state. And that’s an active field of research to understand all this feedback mechanism in the system that could really accelerate warming.”