“If you recognize that the Arctic really is the gateway to climate change, and that we need some means of taking a regular pulse check on how things are in that critical area, the report card represents, あなたがするなら, a bit of a snapshot,” NOAA Administrator Richard Spinrad told CNN.
“That’s why it’s important, just like going to your doctor for an annual physical,” 彼が追加した. “You want to get a consistent, comparable set of observations.”
この夏, the Greenland ice sheet experienced three extreme melt events in the period studied
, レポートによると. For people who live far from the Arctic and may think of the region as something in distance
, Twila Moon
, the lead editor of the report and scientist with the National Snow and Ice Data Center
, explains that it’s all connected
, especially when it comes to ice melt
As the Greenland ice sheet thaws, that loss of ice causes sea levels to rise, which can be strongly felt in places far from the Arctic, including low-lying Pacific Islands and coastal cities. These impacts can lead to coastal erosion, salt water intrusion in freshwater drinking resources, as well as disruptions to sewer and water systems.
加えて, the Arctic’s thawing permafrost is also releasing more greenhouse gases into the atmosphere, further exacerbating the warming of the entire planet.
“The Arctic report card this year is showing us how well connected we as people are to the environmental changes happening in the globe, and how these cascading disruptions in one place is not isolated and might influence other parts of the system,” Moon told CNN.
“We now live at a time that is fundamentally different from the past and will be experiencing ongoing change into the future.”
A recent scientific report on the region showed that the Arctic Ocean had been warming
以来 onset of the 20th century
, decades earlier than previously thought
While the year studied was the seventh warmest on record in the Arctic, the period from October to December 2020 was the warmest on record. The Arctic continues to warm more than twice as fast as the rest of the globe.
The summer also brought warmer-than-usual temperatures
. An August heatwave triggered rain to fall at the summit of Greenland instead of snow for the first time on record. As temperatures at the summit rose above freezing for the third time in less than a decade
, the warm air fueled an extreme rain event that dumped
7 billion tons of water on the ice sheet
A report published after that event found this was likely to happen more often
. The Arctic is expected to experience more rain than snow some time between
2060 そして 2070, marking a major transition in its precipitation patterns as the climate crisis jacks up temperatures in the region
“Things that happen in the Arctic don’t specifically stay in the Arctic
,” Michelle McCrystall
, climate researcher at the University of Manitoba in Winnipeg
, who is not involved with the report
. “The fact that there could be an increase in emissions from permafrost thaw or an increase in global sea level rise
, it is a global problem
, and it needs a global answer.
Beavers, ships, and permafrost hazards
The NOAA report card also found, from satellite images and other data, that North American beavers are taking over the Arctic tundra of Alaska, doubling their ponds in the last two decades. Scientists are also mapping beaver ponds in Canada and Asia.
That’s an issue because beavers gnaw through and fell trees, and build dams, which can flood valleys and form new lakes that contribute to the thawing of the frozen permafrost soil
. When permafrost melts
, it emits large amounts of methane
, a more potent greenhouse gas than carbon dioxide
Both the dwindling sea ice and shifting marine habitats are also bringing an uptick in shipping traffic to the Arctic. The rise in human activity, coupled with the environmental changes it brings, is drastically altering the marine soundscape, レポートによると.
“In your home, if you notice that one of your lights is flickering, you’d wonder if you got a problem with the electricity,” Spinrad told CNN.
“But if you notice all the lights are flickering, the air conditioning is not working, and there are some leaks in the plumbing, you’d start saying we have a serious problem overall with the home, not just an isolated set of incidents.”
Spinrad said it’s the aggregation of a wetter, less icy, greener and warmer Arctic that suggests the region is fundamentally different from the one the planet has known centuries, or even decades ago.
レポートはそれを発見しました, as the planet rapidly warms, retreating glaciers and thawing permafrost are already threatening the lives of the roughly five million people living in the permafrost region of the Northern Hemisphere, creating a cascading effect through economies, インフラストラクチャー, and national security of local Arctic communities.
Glacial retreat is also exposing already arduous slopes that are prone to destabilize, which in the presence of deep water, can cause landslide-fueled tsunamis, flooding and debris flow that could potentially be deadly, the report shows.
This last year adds to another stretch of exceptionally high tundra greenness since the report began; しかしながら, recent extreme events and other local influences such melting permafrost thaw or wildfires are also priming the landscape to become browner.
Moon said that as the whole world is experiencing some level of impact from the climate crisis, people should be able to empathize with communities in the Arctic and not view the region as a disconnected place.
“The people of the Arctic are similarly experiencing extreme events and conditions that they’ve never before witnessed or have to deal with,” said Moon.
“So on a very human scale, we are all finding ourselves in a world that is now fundamentally changed from the the environmental conditions of the last many decades and centuries.”