时间:2025-09-17 01:17:48 来源:网络整理编辑:百科
The Himalayas pierce the sky. But they've been overshadowed. The accelerated melting in the Arctic -
The Himalayas pierce the sky. But they've been overshadowed.
The accelerated melting in the Arctic -- the fastest warming region on Earth -- and the Antarctic -- home to the largest ice sheets on the planet -- certainly demand widespread scientific and media attention. Yet beyond the continually grim news from the north and south poles is the melting of the "third pole," known as the Hindu Kush Himalaya region. Spreading over 2,000 miles across eight nations (from Afghanistan to Myanmar), these mountainous lands are home to the third-largest stores of ice on the planet and provide water to hundreds of millions of people.
A new report written by 210 scientists emphasizes the dramatic melting there this century. The International Center for Integrated Mountain Development (ICIMOD) -- a Nepal-based intergovernmental research organization -- released the 638-page report on Monday, concluding that these glaciers are expected to lose immense amounts of ice as the mountains warm.
Under the most optimistic conditions, the report found that over a third of the ice will vanish by the century's end. But under more extreme climate scenarios -- wherein global climate efforts fail -- two-thirds of these mighty glaciers could disappear, with overall ice losses of a whopping 90 percent.
"Glacier-wise, it's not a great story," Joseph Shea, one of the report's lead authors and an assistant professor of environmental geomatics at the University of Northern British Columbia, said in an interview.
"You go up [to the glaciers] and see that the signs of recent loss are pretty substantial," said Shea, who spent four years living in Nepal, watching firsthand as the ice thinned and, in some cases, vanished.
"The punchline is the glaciers are receding in response to changes in temperature and precipitation -- they’re wasting away," Alex Gardner, a NASA glaciologist who had no role in the report, said in an interview.
Shea emphasized the importance of reining in heat-trapping carbon emissions ("Every kilogram we don’t emit helps"), but noted that the melting will still be considerable this century. The atmosphere is already loaded with carbon dioxide, a potent greenhouse gas that is at its highest levels in some 15 million years.
Under the most ambitious scenario of limiting global warming to just 1.5 degrees Celsius (or 2.7 Fahrenheit) above pre-industrial revolution levels in this century, the report finds that the Hindu Kush Himalaya region will lose one in three of its glaciers.
"It's not a great story"
But this scenario is no longer realistic.
"We're not gonna hit 1.5 C," acknowledged Shea. "We’re gonna blow by that."
The reasons are simple. The four biggest carbon emitters -- China, the U.S., India, and EU -- haven't yet decreased their emissions in a sustained, impactful way. Last year, carbon emissions in the U.S. popped up.
SEE ALSO:It's damn cold, but heat records in the U.S. still dominateAnd even with 2 degrees Celsius of warming -- which is also a hugely ambitious climate target -- around half of the Hindu Kush Himalaya region's glaciers are expected to vanish by century's end, the report concluded.
While these are enormous numbers, they're not too shocking. In fact, they're consistent with mainstream climate science.
"There are no surprises," Ted Scambos, a senior research scientist at the National Snow and Ice Data Center who had no involvement in the report, said in an interview. "It's happening everywhere."
"I don’t know of any glaciated range that isn’t showing a loss of ice," Scambos added.
"What the global signal tells us is everything is in a state of rapid retreat," added Gardner.
The crux of the problem is local warming on the mountains. The line that separates where it's cold enough to make snow, called the "equilibrium line," keeps rising higher, which means less snow and more melting.
"That line pushes up and you expose a bunch of ice to melting," said Shea.
Thinning glaciers pose momentous problems for the millions of people living below.
"It's not just a symbol of climate change," said Gardner. "These glaciers will have meaningful consequences for the population."
Glaciers act like batteries, he said. "They don't make water, they store it and release it." During warmer and dryer times, people and farmers depend on these natural batteries to release water, especially when water becomes a scarce, critical resource.
"They are incredibly valuable downstream resources," said Gardner.
But, sometimes, there's too much water. Less snow means more rain and a quicker run-off into some of the planet's largest rivers, like the Ganges and Yellow. This translates into surges of water, extreme flooding, and crop devastation, the report stated.
In the Himalayas and around the globe, the glacier narrative is clear. But just how much they'll ultimately thin and recede above the clouds is contingent upon human-generated carbon emissions. Already, the planet is the warmest it's been in 120,000 years, and ancient glaciers are a visible victim.
"When you get up there [to the glaciers] and visually see it, it's stunning," said Shea.
"How long have they existed there, and how quickly have we got rid of them?" mused Gardner.
You can now play 'Solitaire' and 'Tic2025-09-17 00:42
電影《拯救嫌疑人》西安路演 張末李鴻其與觀眾共話現實議題2025-09-17 00:32
愛奇藝大年初一上線《渴望》《金婚》《大宅門》等25部經典國劇2025-09-17 00:00
獨孤天下播出一周年 徐正溪的太師才是永遠的白月光2025-09-16 23:51
Early Apple2025-09-16 23:45
《誌願軍》背後資本強悍,匯聚電影圈半壁江山 ,吳京和這位大佬入局2025-09-16 23:44
“明星IP”哆啦A夢現身首映禮 《大雄與天空的理想鄉》將與觀眾歡度六一2025-09-16 23:07
6天破3000萬播放!《冰火鳳》特效驚豔獲讚 ,朱聖禕大受好評2025-09-16 23:00
Old lady swatting at a cat ends up in Photoshop battle2025-09-16 22:32
CF網劇另類選角賺足眼球 ,國民IP影視改編勢頭強勁2025-09-16 22:31
Whyd voice2025-09-17 01:07
酷狗歌手兔子牙上快樂大本營 !何炅:氣質好歌還唱的棒2025-09-17 00:49
電影《葉榆澤的星空》開機儀式在雲南大理舉行2025-09-17 00:45
每一部都非常硬核 這些讓人腎上腺素狂飆的懸疑劇今年都蓄勢待播2025-09-16 23:54
We asked linguists if Donald Trump speaks like that on purpose2025-09-16 23:25
民國巨製《義海》安徽衛視熱血收官 情義不滅做市場清流2025-09-16 23:09
《幕後之王》黃燦燦詮釋“檸檬精” 想嚐試更多類型角色2025-09-16 23:08
2.2億大片網絡上線,演員陣容清一色大牌,如何回本成為難題2025-09-16 22:53
Here's what 'Game of Thrones' actors get up to between takes2025-09-16 22:52
《野生廚房》汪涵秀“左手書法” 歐弟字太醜遭林更新狂“吐槽”2025-09-16 22:37