by The year 2023 broke the record for the hottest Arctic summer, and people and ecosystems across the region felt the impact. Wildfires have forced evacuations across Canada. Greenland was so warm that a research station at the summit of the ice sheet recorded a melt in late June, only the fifth melt 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 go back to about 1900, it is almost certain that this was the warmest Arctic summer in centuries.
The year started off unusually wet, and snow accumulation during the winter of 2022-23 was above average across much of the Arctic. But by May, high spring temperatures left North America’s snowpack at record levels, exposing land that warmed and dried quickly and fueled lightning-triggered fires across Canada.
Temperatures in the Arctic are rising more than three times faster than the global average, so it’s no surprise that the Arctic has seen its hottest summer and sixth warmest year on record.
In the Arctic Report Card 2023, released on 12 December, we brought together 82 Arctic scientists from around the world to identify the vital signs of the Arctic, the changes taking place and their effects on lives across the region and around the world. to consider.
Cascading effects of warming across the Arctic
In an area as large as the Arctic, setting a new temperature record for a season of two tenths of a degree Fahrenheit (0.1 degree Celsius) would be significant. Summer 2023 – July, August and September – broke the previous record, set in 2016, by four times. 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 contribute to a warming climate.
The winter snow cover melted early across large parts of northern Canada, giving the Sun an extra month to warm the exposed ground. The heat and lack of moisture dried up organic matter on and just below the surface; by November, 70,000 square miles (180,000 square kilometers) had burned across Canada, about a fifth of it in the Northwest Territories.
The very hot weather in May and June 2023 in the Northwest Territories also contributed to the mighty Mackenzie River, which sent huge amounts of warm water into the Beaufort Sea from the north. The warm water soon melted the sea ice, and currents also carried it westward toward Alaska, where the Mackenzie River water contributed to early sea ice loss along most of the Arctic Alaska and with increased tundra vegetation growth.
Similar warming in western Siberia also contributed to rapid melting of sea ice and high sea surface temperatures in the Kara and Laptev seas north of Russia.
Declining sea ice in the Arctic has contributed significantly to the dramatic increase in average fall temperatures across the region. Dark open water absorbs the sun’s rays during summer and, in autumn, acts as a heat pad, releasing heat back into the atmosphere. Even thin sea ice can severely limit this heat transfer and allow dramatic cooling of air just above the surface, but the past 17 years have seen the lowest sea ice extents on record.
Submarine permafrost: A climate wild card
The report includes 12 essays that examine the effects of climate change and ecosystems across the Arctic and how communities are adapting. One is a distress call about the risks of submarine permafrost, a potentially dangerous “out of sight, out of mind” situation.
Submarine permafrost is frozen soil on the ocean floor that is rich in organic matter. It has been melting gradually since it was submerged after the retreat of the Northern Hemisphere ice sheets thousands of years ago. Today, warmer ocean temperatures are likely to contribute to the melting of this hidden permafrost.
Just as with permafrost on land, when underwater permafrost melts, the organic matter in it decays and releases methane and carbon dioxide – greenhouse gases that contribute to global warming and fuel ocean acidification.
Scientists estimate that nearly 1 million square miles (2.5 million square kilometers) of permafrost remains underwater, but with little research outside the Beaufort Sea and Kara Sea, no one knows how soon it may release its supposed gas. of heat or how severe the heating effects will be. .
Salmon, reindeer and human lives
For many people living in the Arctic, climate change is already affecting their lives and livelihoods.
Indigenous observers describe changes in sea ice that many people rely on for subsistence hunting and coastal protection from storms. They noted changes in wind patterns and increasingly intense ocean storms. On land, rising temperatures are making river ice less reliable for travel, and sinking permafrost is melting roads and destabilizing homes.
Clear and dramatic changes are occurring within human life, and they have cut to the core of indigenous cultures to the point that people are having to change the way they put food on the table.
Western Alaska communities that rely on Chinook salmon saw another year of extremely low numbers of adult salmon returns in 2023, a shortage that affects both cultural practices and food security. Yukon River Chinook have decreased in size by about 6% since the 1970s, and they have fewer offspring. Then, in 2019, the year many of this year’s returning Chinook salmon were born, extremely warm river water killed many young.
The returning Chinook salmon population has been so small for the past two years that the fishery has even been closed for the highest-priority subsistence harvest, in hopes that the salmon population will rebound.
The inability to fish, or hunt seals because the sea ice has thinned, is not just a matter of food. Time spent at fish camps is vital to many Alaskan native cultures and traditions, and kids are increasingly missing out on that experience.
As indigenous communities adapt to ecosystem changes, people are also working to heal their landscapes.
In Finland, an effort to restore damaged reindeer habitat in collaboration with Sámi reindeer herders is helping to preserve their way of life. For decades, commercial logging allowed the removal of hundreds or thousands of square miles of reindeer bog habitat.
The Sámi and their partners are working to replant peat and reforest 125,000 acres (52,000 hectares) of peatlands for reindeer grazing. Degraded peatlands also release greenhouse gases, which contribute to climate change. Keeping them healthy helps capture and store carbon away from the atmosphere.
The Arctic Report Card 2023 is a reminder of what is at stake, the risks and the growing planet and the lives and cultures already affected by climate change.
This article is republished from The Conversation, a non-profit, independent news organization that brings you reliable facts and analysis to help you make sense of our complex world. 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.
Read more:
Rick Thoman receives funding from the National Oceanic and Atmospheric Administration (NOAA) to serve as editor for the Arctic Report Card.
Matthew L. Druckenmiller receives funding from the National Oceanic and Atmospheric Administration (NOAA) for serving as an editor for the Arctic Report Card.
Twila A. Moon receives funding from the National Oceanic and Atmospheric Administration (NOAA) to serve as editor of the Arctic Report Card.
