The year 2023 broke the record for the warmest summer in the Arctic, and people and ecosystems across the region felt the impact. Wildfires forced evacuations across Canada. Greenland was so warm that a research station at the top of the ice sheet recorded the melting in late June, only the fifth melting event on record. Sea surface temperatures in the Barents, Kara, Laptev and Beaufort Seas were 9 to 12 degrees Fahrenheit (5 to 7 degrees Celsius) above normal in August.
Although reliable instrument measurements only date back to around 1900, it is almost certain that this was the hottest summer in the Arctic in centuries.
The year started unusually wet and snow accumulation during the winter of 2022-2023 was above average across much of the Arctic. But by May, high spring temperatures had pushed North American snowpack to record lows, exposing soil that quickly warmed and dried, sparking lightning-triggered fires across Canada.
Temperatures in the Arctic have been rising more than three times faster than the global average, so it is not surprising that the Arctic has had its warmest summer and sixth warmest year on record.
In the Arctic Report Card 2023, released on December 12, we brought together 82 Arctic scientists from around the world to assess the vital signs of the Arctic, the coming changes and their impacts on lives in the region and around the world.
The cascading effects of heat across the Arctic
In an area the size of the Arctic, setting a new temperature record for a season with a warming of two-tenths of a degree Fahrenheit (0.1 degrees Celsius) would be significant. In the summer of 2023 – July, August and September – the previous record from 2016 was quadrupled. Temperatures were above normal almost everywhere in the Arctic.
A closer look at events in Canada’s Northwest Territories shows how rising air temperatures, declining sea ice and warming water temperatures are reinforcing each other in a warming climate.
Winter snow cover melted early in much of northern Canada, giving the sun an extra month to warm exposed ground. The heat and lack of moisture caused organic material to dry up and just below the surface; by November, 180,000 square kilometers had burned across Canada, with about a fifth of that in the Northwest Territories.
The very warm weather in May and June 2023 in the Northwest Territories also heated the mighty Mackenzie River, sending huge amounts of warm water to the Beaufort Sea to the north. The warm water melted sea ice early, and currents also carried it westward toward Alaska, where Mackenzie River waters contributed to the early loss of sea ice along most of Northeast Alaska and increased growth of the tundra vegetation.
Similar warmth in western Siberia also contributed to rapid sea ice melting and high sea surface temperatures in the Kara and Laptev seas north of Russia.
Declining sea ice in the Arctic has contributed greatly to the dramatic increase in average autumn temperatures across the region. Dark open water absorbs the sun’s rays during the summer and acts as a heating pad in the fall, releasing heat back into the atmosphere. Even thin sea ice can greatly limit this heat transfer and allow dramatic cooling of the air just above the surface, but the past 17 years have seen the lowest sea ice extent on record.
Submarine permafrost: a climate wildcard
The report contains twelve essays examining the effects of climate and ecosystem changes in the Arctic and how communities are adapting. One of these is a wake-up call about the risks of undersea permafrost, a potentially dangerous case of ‘out of sight, out of mind’.
Submarine permafrost is frozen soil in the ocean floor that is rich in organic matter. It has been gradually thawing since it was flooded after the Northern Hemisphere ice caps retreated thousands of years ago. Today, warmer ocean temperatures are likely accelerating the thawing of this hidden permafrost.
As with permafrost on land, when submarine permafrost thaws, the organic material it contains decays, releasing methane and carbon dioxide – greenhouse gases that contribute to global warming and worsen ocean acidification.
Scientists estimate that nearly 2.5 million square kilometers of submarine permafrost remains, but with little research beyond the Beaufort Sea and Kara Sea, no one knows how quickly it will release its greenhouse gases or how intense its warming effects will be. .
Salmon, reindeer and human lives
For many people in the Arctic, climate change is already disrupting people’s lives and livelihoods.
Indigenous observers describe changes in the sea ice that many people depend on for both subsistence hunting and coastal protection from storms. They have noticed shifts in wind patterns and increasingly intense ocean storms. On land, rising temperatures are making river ice less reliable for transportation, and thawing permafrost is causing roads to sink and homes to be destabilized.
There are clear and dramatic changes taking place within human lifetimes, and they are cutting to the core of indigenous cultures to the point that people must change the way they put food on the table.
Communities in Western Alaska that rely on Chinook salmon saw another year of extremely low numbers of returning adult salmon in 2023, a scarcity that is disrupting both cultural practices and food security. The Yukon River Chinook has declined in size by about 6% since the 1970s and is producing fewer offspring. Then in 2019, the year many of this year’s returning Chinook salmon were born, exceptionally warm river water killed many of the fry.
The returning population of Chinook salmon has been so small over the past two years that the fishery has been closed even for subsistence harvesting, which is the top priority, in the hope that the salmon population will recover.
The inability to fish or hunt seals because the sea ice has thinned is not just a food problem. Time spent at fishing camps is critical to many Alaska Native cultures and traditions, and children are increasingly missing out on that experience.
As indigenous communities adapt to changes in the ecosystem, people are also working to restore their landscapes.
In Finland, an effort to restore damaged reindeer habitat in collaboration with Sámi reindeer herders is helping preserve their way of life. For decades, commercial logging was allowed to destroy hundreds to thousands of square kilometers of reindeer peat habitat.
The Sámi and their partners are working to replant grass and replant 52,000 hectares of peatlands for reindeer grazing. Degraded peatlands also emit greenhouse gases, which contribute to climate change. Keeping them healthy captures and stores carbon from the atmosphere.
The Arctic Report Card 2023 reminds us of what is at stake: both the risks of planetary warming and the lives and cultures already being disrupted by climate change.
This article is republished from The Conversation, an independent nonprofit organization providing facts and trusted analysis to help you understand our complex world. Do you like this article? Subscribe to our weekly newsletter.
It was written by: Rick Thoman, University of Alaska Fairbanks; Matthew L. Druckenmiller, University of Colorado Boulderand Twila A. Moon, University of Colorado Boulder.
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Rick Thoman receives funding from the National Oceanic and Atmospheric Administration (NOAA) for his work as editor of the Arctic Report Card.
Matthew L. Druckenmiller receives funding from the National Oceanic and Atmospheric Administration (NOAA) for his work as editor of the Arctic Report Card.
Twila A. Moon receives funding from the National Oceanic and Atmospheric Administration (NOAA) for her work as editor of the Arctic Report Card.