青藏高原冰川融化速度驚人將影響亞洲淡水供應

With temperatures rising four times faster than anywhere else in Asia, the Tibetan Plateau might soon lose most of its glacier and permafrost, affecting water supplies throughout Asia, Chinese scientists say.

青藏高原的氣溫上升速度比亞洲其它地區快了四倍，中國科學家說青藏高原上絕大部分的冰川和永動層或許不久就將消失殆盡，這將影響亞洲各地的淡水供應。

Long known as the "roof of the world," the Tibetan Plateau is about the size of Western Europe and supplies water to nearly 2 billion people in Asia as the source of several major rivers, including the Yangze, Mekong, Salween (Gyalmo Ngulchu), Indus, Brahmaputra and Yellow rivers.

作爲早就聞名遐邇的“世界屋脊”，青藏高原的面積和西歐差不多。這一地區是包括長江、湄公河、薩爾溫江、印度河、雅魯藏布江和黃河在內的幾條大河的源頭，向亞洲近20億人供應着淡水。

But because of the impact of climate change, the glaciers are retreating rapidly, grasslands are shrinking as desertification expands, regional precipitation has become irregular, water levels are dropping in major rivers and the permafrost is thawing.

但受氣候變化影響，這裏的冰川迅速消退，草原面積不斷減小，荒漠化面積不斷增加，區域降水反常，幾條大河的水位不斷下降，永凍層也在持續融化。

The melting of Tibetan glaciers, the largest mass of frozen fresh water outside the polar regions, is linked to many environmental consequences both locally and globally, including heat waves in Europe, according to some studies.

青藏高原儲藏着除兩極地區以外最多的冰凍淡水。一些研究顯示，這一地區的冰川融化與多種區域性和全球性的環境影響有關，比如歐洲的熱浪。

Glacial retreat

冰川消融

Chinese officials estimate Tibet holds 14.5 percent of the world's total glacier mass. While there are a few different theories on what is causing the glaciers to melt, researchers agree the pace is staggering.

中國官方預計西藏地區擁有佔全世界14.5%的冰川儲量。儘管對引起冰川融化的原因還存在不同說法，但研究者們都認爲青藏高原冰川消融的速度是驚人的。

China's state-run Xinhua news agency reported in April that an average of 247 square kilometers of glacier is disappearing annually, and that some 7,600 square kilometers of glacier, or about 18 percent of the total, has disappeared since the 1950s.

今年4月，中國官方的新華社報道，青藏高原平均每年有247平方公里的冰川消融。自上世紀50年代以來，已經有大約7600平方公里的冰川消失，這佔到青藏高原冰川總量的大約18%。

Zhang Mingxing, a Chinese official who heads the Tibet Mountaineering Administration, said the glacier at the Everest base camp, 5,200 meters above sea level, has already disappeared. "There is nothing but stones (left)," he was quoted as saying by Xinhua.

西藏登山運動管理中心主任張明興說，在海拔5200米的艾佛勒斯峯（珠穆朗瑪峯）大本營區的冰川已經消失。新華社援引他的描述說，那裏就剩下石頭了。

Prior Chinese research of substances within Tibetan glaciers indicated carbon from forest fires, crop burning and domestic cooking stoves from India have caused the melting. While these could be contributing factors, scientists say the global rise in temperatures is indisputably the primary cause.

在對冰川內的物質進行研究之後，之前的一些中國研究人員表示，森林大火、焚燒秸稈以及印度家庭做飯用的廚竈等造成的碳排放都導致了青藏高原冰川的融化。科研人員說，儘管可能還有其它因素，但全球氣溫升高正在成爲導致冰川融化的一個無可辯駁的原因。

Tibetans say there has been a drastic change of temperature since 1980s. One U.S.-based Tibetan who recently returned to Lhasa expressed shock at seeing the climatological impact on people's clothing style. "When I lived in Lhasa, it was very rare that people could walk outside in T-shirts," said the man, who asked that his name be withheld. "Now people are walking in shorts!"

西藏地區居民表示自上世紀80年代以來，這一地區的氣溫發生了劇烈的變化。一位居住在美國、不願透露姓名的西藏人表示當他最近回到拉薩時，他被人們因氣候變化導致的穿衣風格的改變震驚了。他說：“當我在拉薩生活的時候，很少能見到人們穿着T恤衫走出戶外的。現在走在拉薩街頭的人都是短衣短褲了。”

National Geographic reported in 2010 that one glacier was retreating by about 300 meters a year, the length of a U.S. football field.

《國家地理》雜誌在2010年報告一處冰川正在以每年大約300米的速度消退，這與一個美式橄欖球場的長度大致相當。

As early as 2009, China's leading scientist on glaciers, Qin Dahe, said glaciers on the Tibetan Plateau were melting faster than in any other part of the world. In the short term, he warned, the melt would trigger more flooding and mudslides; in the long term: "water supplies in the region will be in peril."

早在2009年，中國從事冰川研究的帶頭人秦大河就表示青藏高原的冰川消融速度比世界上其它任何地方都快。他曾警告說冰川消融在短期內就可能導致更多的洪水和泥石流，長遠看來這一地區的淡水供應將受到威脅。

Some researchers have predicted that most of the Himalayan glaciers will be gone in 20 years.

一些研究人員已經預測，喜馬拉雅山地區的大部分冰川在20年內將消失殆盡。

Water needs

淡水需求

Those shrinking glaciers feed some of the largest rivers that run through China, India, Pakistan, Bangladesh, Burma, Laos, Thailand, Vietnam and Cambodia.

那些正在消退的冰川是一些世界最大河流的源頭，這些河流流經中國、印度、巴基斯坦、孟加拉國、緬甸、老撾、泰國、越南以及柬埔寨。

"Water is the most important resource that this region has, the common region of Tibet part of China, India, Bhutan and all of that," said R. Rangachari, honorary scholar at India's Center for Policy Research and former secretary of the Ministry of Water Resources of India.

印度政策研究中心榮譽學者蘭加夏裏（R. Rangachari）說：“這一區域、也就是由中國的藏區、印度和不丹等等的共同區域所擁有的最重要的資源就是水。”蘭加夏裏曾擔任印度水利部部長，

"Water is the key to removing poverty, generation of power, agriculture, et cetera," he told VOA's Tibetan service.

他還對美國之音藏語組說：“水資源是消除貧困、發電和發展農業的關鍵。”

A former researcher of Tibetan Plateau climate change for the Chinese Academy of Science, who spoke on the condition of anonymity, said diminished glacial runoff had already reduced water levels on the Yangtze and Yellow rivers. "The headwaters for any major rivers come from (the) Tibetan Plateau and there is (a) lesser water supply to those head rivers," he said.

一位前中國科學院青藏高原氣候變化問題研究員表示，在西藏的部分地區，水資源的供應已經在減少，像長江、黃河這樣的河流水位也在下降。這位匿名人士還透露：“另一個現象就是對主要河流的供水在減少。源頭在青藏高原的主要河流的上游水量在減少，對那些源頭河流的供水也在變少。”

China's Ministry of Water Resources announced in 2013 that as many as 28,000 smaller rivers in China had abruptly disappeared by 2011. While Beijing did not cite specific causes, the anonymous researcher said warming on the Tibetan Plateau was at least partly to blame.

中國水利部在2013年公佈一項數據，截至2011年，中國有多達28000條較小的河流迅速消失。雖然水利部沒有提及原因，但那位前中科院研究員表示青藏高原氣候變暖是部分原因。

"Another important reason is the meltdown of the permafrost soil," which leads to subterranean water drainage, he said. "Like when you have (a) thick sponge." The latest research conducted by the Chinese Academy of Science predicted that more than 80 percent of Tibetan Plateau permafrost could be gone by the year 2100, and that almost 40 percent of it would be gone within the "near future."

他說：“另一個重要原因就是永久凍土融化。”他說，這帶來地下水的排水問題，“就像你手裏的海綿變厚一樣。”中科院的最新研究預測，到2100年，青藏高原上可能將有超過80%的永久凍土消失，有近40%的永久凍土在“不久的將來”就可能消失。

Increased risk of conflict

衝突風險

The apparent changes in the Tibetan Plateau have raised concern about the potential for water-security conflicts in the region, particularly between China and India.

青藏高原上明顯的氣候變化增加了人們對各方，特別是中國和印度，在水資源保障問題上發生衝突的擔憂。

To mitigate the environmental impact, China has stepped up construction of dams along rivers cascading from the Tibetan Plateau, despite complaints from downstream nations that need the water.

在西藏環境發生明顯變化的同時，中國不顧下游國家的抱怨，一直在青藏高原的河流上游加緊建設大壩。

In fact, the Salween remains the only Tibetan river that has not yet been interrupted by major dams; Tibet's Yarlung Tsangpo River, which feeds India's Brahmaputra River, recently saw construction of a single dam.

實際上，在源頭在西藏的主要河流中，只有薩爾溫河沒有重要大壩的阻隔。中國最近在雅魯藏布江上建成了一座大壩，雅魯藏布江是印度布拉馬普特拉河的源頭河流。

According to Rangachari, India takes the water issues seriously.

蘭加夏裏表示印度非常重視水資源問題。

"Nobody wants to hand over their right to do something — (especially) what the other is doing," he said. "Political boundaries might be created by man, but geography is created by God."

他說：“沒人想把做事的權利拱手讓人，特別是這件事是別人正在做的。政治界線是人爲的，但地理是神定的。