美国国家公共电台 NPR--The Arctic is heating up nearly four times faster than the whole planet, study finds

The Arctic is heating up nearly four times faster than the whole planet, study finds

Transcript¹

The Arctic is heating up nearly four times faster than the Earth as a whole, according to new research. The findings are a reminder² that the people, plants and animals in polar regions are experiencing rapid, and disastrous³, climate change.

Scientists previously⁴ estimated that the Arctic is heating up about twice as fast as the globe overall. The new study finds that is a significant underestimate of recent warming. In the last 43 years, the region has warmed 3.8 times faster than the planet as a whole, the authors find.

The study focuses on the period between 1979, when reliable satellite measurements of global temperatures began, and 2021.

"The Arctic is more sensitive to global warming than previously thought," says Mika Rantanen of the Finnish Meteorological Institute, who is one of the authors of the study published in the journal Communications Earth & Environment.

There have been hints in recent years that the Arctic is heating up even more quickly than computer models predicted. Heat waves in the far North have driven wildfires and jaw-dropping ice melt in the circumpolar region that includes Alaska, Arctic Canada, Greenland, Scandinavia and Siberia.

"This will probably be a bit of a surprise, but also kind of extra motivation perhaps," says Richard Davy, a climate scientist at Nansen Environmental and Remote Sensing Center in Norway, who was not involved in the new study. "Things are moving faster than we could have expected from the model projections⁵."

There are many reasons why the Arctic is heating up more quickly than other parts of the Earth. Changes in the amount of air pollution coming from Europe and natural multi-decade climate variations likely play a role. But human-caused global warming is the underlying⁶ reason that the Arctic, and the planet as a whole, are heating up.

Loss of sea ice is one of the clearest drivers of Arctic warming. The Arctic Circle is mostly ocean, which used to be frozen for most or all of the year. But permanent sea ice is steadily⁷ shrinking, and seasonal⁸ ice is melting earlier in the year and re-forming later.

That means more open water. But while ice is bright and reflects heat from the sun, water is darker and absorbs it. That heat helps melt more ice, which means more water to trap more heat – the loop feeds on itself, accelerating warming in the Arctic.

"That's why the temperature trends are the highest [in] those areas where the sea ice has declined most," explains Rantanen. There are hotspots in the Bering Sea over Northern Europe and Siberia, which are heating up about seven times faster than the global average, the study estimates.

Rapid Arctic warming affects people living far from the Arctic circle. For example, there is evidence that weather patterns are shifting across the U.S. and Europe as sea ice melts, and many marine⁹ species migrate between the tropics and the Arctic each year. "What happens in the Arctic doesn't just stay in the Arctic," says Davy.

The new research also finds that the advanced computer models that scientists use to understand how the global climate is changing now, and will change in the future, struggle to capture the relative speed of Arctic warming. That suggests that future models may need to be adjusted to better capture the realities of global warming in polar regions, although this study did not tease apart what exactly is missing from current models.

"The paper's finding that climate models tend to underestimate the warming ratio [between the Arctic and the Earth as a whole] is really interesting," says Kyle Armour¹⁰, a climate scientist at the University of Washington who was not involved in the new study.

Previous studies have found that computer models actually do a good job estimating how much the Arctic has heated up, but that they tend to overestimate¹¹ how much hotter the whole planet is, Armour explains. That means the models' comparison between Arctic warming and overall warming ends up being incorrect.

"We have more work to do to figure out the source of this model bias," says Armour. And that work is increasingly important, because world leaders use climate models to understand what the future holds and how to avoid even more catastrophic warming.

1 transcript   

n.抄本，誊本，副本，肄业证书

参考例句：

• A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
• They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。

2 reminder   

n.提醒物，纪念品；暗示，提示

参考例句：

• I have had another reminder from the library.我又收到图书馆的催还单。
• It always took a final reminder to get her to pay her share of the rent.总是得发给她一份最后催缴通知，她才付应该交的房租。

3 disastrous   

adj.灾难性的，造成灾害的；极坏的，很糟的

参考例句：

• The heavy rainstorm caused a disastrous flood.暴雨成灾。
• Her investment had disastrous consequences.She lost everything she owned.她的投资结果很惨，血本无归。

4 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

5 projections   

预测( projection的名词复数 )； 投影； 投掷； 突起物

参考例句：

• Their sales projections are a total thumbsuck. 他们的销售量预测纯属估计。
• The council has revised its projections of funding requirements upwards. 地方议会调高了对资金需求的预测。

6 underlying   

adj.在下面的，含蓄的，潜在的

参考例句：

• The underlying theme of the novel is very serious.小说隐含的主题是十分严肃的。
• This word has its underlying meaning.这个单词有它潜在的含义。

7 steadily   

adv.稳定地；不变地；持续地

参考例句：

• The scope of man's use of natural resources will steadily grow.人类利用自然资源的广度将日益扩大。
• Our educational reform was steadily led onto the correct path.我们的教学改革慢慢上轨道了。

8 seasonal   

adj.季节的，季节性的

参考例句：

• The town relies on the seasonal tourist industry for jobs.这个城镇依靠季节性旅游业提供就业机会。
• The hors d'oeuvre is seasonal vegetables.餐前小吃是应时蔬菜。

9 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

10 armour   

（=armor）n.盔甲；装甲部队

参考例句：

• His body was encased in shining armour.他全身披着明晃晃的甲胄。
• Bulletproof cars sheathed in armour.防弹车护有装甲。

11 overestimate   

v.估计过高，过高评价

参考例句：

• Don't overestimate seriousness of the problem.别把问题看重了。
• We overestimate our influence and our nuisance value.我们过高地估计了自己的影响力和破坏作用。