Commentary: 2021 Arctic Report Card reveals a (human) story of cascading disruption | Opinion

The Arctic has long been portrayed as a place far from the end of the earth, disconnected from everyday common experience. But as the planet warms rapidly, what is happening in this icy region, where temperatures are rising twice as fast as the rest of the globe, is increasingly affecting lives around the world.

On December 14, a team of 111 scientists from 12 countries released the 16th Annual Arctic Report, an annual update on the state of the Arctic system. We are Arctic scientists and the editors of this peer-reviewed assessment. In the report, we take a diverse look at the interconnected physical, ecological and human components of the region.

Like an annual check-up with a doctor, the report assesses vital signs of the Arctic – including surface air temperatures, sea surface temperatures, sea ice, snow cover, ice cap glacial period, tundra greening, and rates of photosynthesis by ocean algae – while also questioning other health indicators and emerging factors that shed light on the trajectory of Arctic change.

As the report describes, rapid and pronounced man-made warming continues to be the source of most of the changes and ultimately sets the stage for disruptions that affect ecosystems and communities far away. .

followinginduced ice lossArctic sea ice – a central vital sign and one of the most iconic indicators of global climate change – continues to shrink under warming temperatures.

Including data from 2021, 15 of the lowest areas of summer sea ice – the point where ice is at its minimum range for the year – have all occurred in the past 15 years, in a record dating back to 1979 when satellites began to regularly monitor the Region.

Sea ice is also thinning at an alarming rate as the oldest and thickest multi-year ice in the Arctic disappears. This loss of sea ice decreases the capacity of the Arctic to cool the global climate. It can also alter low latitude weather systems to an extent that makes previously rare and impactful weather events, such as droughts, heat waves, and extreme winter storms more likely.

Likewise, the persistent melting of the Greenland ice sheet and other land ice is lifting seas around the world, exacerbating the severity and exposure to coastal flooding, disruption of drinking water and wastewater systems. and coastal erosion for more communities around the world.

A waWetter and wetter arcticThis ice-to-water transition and its effects are evident throughout the arctic system.

The eight major Arctic rivers discharge more fresh water into the Arctic Ocean, reflecting an Arctic-wide increase in water from land due to precipitation, thawing permafrost, and melting seawater. ice cream. Remarkably, the summit of the Greenland ice sheet – at over 10,000 feet above sea level – experienced its very first observed rainfall during the summer of 2021.

These developments indicate a modified and more variable Arctic today. They also give credit to new modeling studies that show the potential for the Arctic to shift from a snow-dominated system to a rain-dominated system in summer and fall as global temperatures reach. than 1.5 degrees Celsius (2.7 F) above the pre-industrial era. time. The world has already warmed by 1.2 C (2.2 F).

Such a shift to more rain and less snow would further transform landscapes, fueling faster retreat of glaciers and loss of permafrost. Thawing permafrost not only affects ecosystems, but also contributes to global warming by allowing previously frozen plant and animal remains to decompose, releasing additional greenhouse gases into the atmosphere.

This year’s report highlights how retreating glaciers and deteriorating permafrost are also increasing threats to human life from sudden and localized floods and landslides. It calls for coordinated international efforts to identify these dangers. More rain in the Arctic will increase these threats even more.

Risihuman impactThe changes and disturbances observed in the Arctic are impacting daily life and actions around the world, either directly or as a stark reminder of a series of human-made damage to climate and ecosystems. .

An Arctic Report Card essay on the northward expansion of beavers in the arctic tundra to exploit new favorable conditions is a case study of how species around the world move as habitats respond to changes climate, and the need for new forms of collaborative monitoring to assess the scale of the resulting ecological transformations.

An essay on marine litter from stranded ships on the Bering Sea coast, posing an immediate threat to food security in the region, reminds us that the threat of micro- and macro-plastics in our oceans is a major challenge in our time.

A report on ship noise increasingly infiltrating the arctic underwater soundscape, to the detriment of marine mammals, is a call to conserve the integrity of natural soundscapes around the world. For example, a recent independent study found that noise caused by human activities and loss of biodiversity deteriorates the springtime soundscapes of songbirds in North America and Europe.

Yet an Arctic Report Card essay by members of the Indigenous Foods Knowledges Network highlights how, despite persistent climate threats to Arctic food systems, Indigenous communities in Alaska weathered the initial disturbances. pandemic food security through their cultural values ​​of sharing and “community first” approaches.

Their cooperation and adaptability offers an important lesson for struggling communities around the world, while reminding everyone that the Arctic itself is a homeland; a place where large-scale disruption is nothing new to its more than one million indigenous peoples, and where solutions have long been found in reciprocal practices.

Arctic connected to the rest of the worldThe Arctic Report Card compiles observations from across the circumpolar north, analyzing them in a polar projection of our planet. This puts the Arctic at the center, with all meridians extending out to the rest of the world.

From this perspective, the Arctic is linked to societies around the world through a myriad of exchanges – the natural circulation of air, ocean and contaminants, the migration of animals and invasive species, as well as anthropogenic transport of people, pollution, goods, and natural resources. A warming Arctic also allows for greater maritime access, as the loss of sea ice allows ships to sink deeper into Arctic waters and for longer periods of time.

These realities highlight the importance of increased international cooperation in conservation, risk mitigation and scientific research.

The Arctic has already undergone rapid and unprecedented environmental and social changes. A warmer, more accessible Arctic means a world more closely connected to each other.

Matthew Druckenmiller is a researcher at the National Snow and Ice Data Center. Rick Thoman is an Alaska climate specialist at the University of Alaska Fairbanks.

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