时间:2025-11-22 03:34:02 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.
Mountains in the Hindu Kush Himalaya region.Credit: Alex Treadway/ICIMOD"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.
Wheat harvesting in Shahr-e-Zarok, Afghanistan.Credit: Alex Treadway/ ICIMODThe 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.
A NASA-led study found that glaciers in Asia are slowing down.Credit: nasaBut, 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.
Visualizing July's astounding global temperature records2025-11-22 03:09
【波盈足球】 世足阿根廷球迷大反擊 破70萬人連署「法國別哭了」 ( 阿根廷,法國 )2025-11-22 02:37
【波盈足球】 世足PK戰沒技術?阿根廷門神「心理戰」整慘法國 ( 馬丁,阿根廷 )2025-11-22 02:32
美伊大戰落幕 英荷順利頭名出線(英格蘭52025-11-22 02:31
Balloon fanatic Tim Kaine is also, of course, very good at harmonica2025-11-22 02:22
【波盈足球】 世足興奮換到梅西千場戰袍交給家人 澳洲球員已不知球衣下落 ( 球衣,梅西 )2025-11-22 02:03
世界杯荷蘭vs阿根廷8進4淘汰賽預測分析:90分鍾難分高下(2022年世界杯有阿根廷嗎)2025-11-22 01:49
【波盈足球】 C羅去沙烏地好處多 ?英媒:可享受國王般的生活 ( 美聯社,阿拉伯 )2025-11-22 01:33
Daughter gives her 1002025-11-22 01:08
卡塔爾世界杯開幕式耗資達1000萬英鎊 主題單曲《夢想家》“打頭陣”(卡塔爾世界杯歌曲hayya)2025-11-22 01:08
Make money or go to Stanford? Katie Ledecky is left with an unfair choice.2025-11-22 03:17
【波盈足球】 世足惡搞阿根廷門將下流慶祝動作 超狂球迷刺青在身上 ( 馬丁,動作 )2025-11-22 03:12
【天下體育NBA】 CBA三消息 :球迷列隊歡送遼籃 ,勇士舊將同天津匯合,陳林堅新職業 ( 男籃,球隊 )2025-11-22 03:12
結婚這麽大事 ,梅西咋就不好好刮刮胡子呢2025-11-22 02:39
U.S. government issues warning on McDonald's recalled wearable devices2025-11-22 02:29
足球守門員的規則有哪些(足球守門員規則詳細視頻)2025-11-22 02:29
阿根廷對波蘭和法國對突尼斯怎麽看?(阿根廷02025-11-22 02:11
正確預測2022世界杯比賽的方式和方法大揭秘(世界杯2022年世界杯的比賽情況)2025-11-22 01:57
Donald Trump's tangled web of Russian influence2025-11-22 01:56
足球戰術丨為什麽這屆世界杯撲出那麽多點球 ?(足球守門員可以進球嗎)2025-11-22 01:01