北極熊將因氣候變化而瀕臨滅絕

Climate change is starving polar bears into extinction, according to research published Monday that predicts the apex carnivores could all but disappear within the span of a human lifetime. In some regions they are already caught in a vicious downward spiral, with shrinking sea ice cutting short the time bears have for hunting seals, scientists reported in Nature Climate Change.

周一發(fā)布的一項研究稱，氣候變化正在餓死北極熊并迫使它們滅絕。該研究預(yù)測，北極熊這一食物鏈頂端的食肉動物可能會在百年內(nèi)幾近滅絕。科學(xué)家在《自然氣候變化》上發(fā)表的報告稱，在部分地區(qū)，由于海冰消融縮短了北極熊捕食海豹的時間，北極熊已經(jīng)陷入數(shù)量螺旋式下降的惡性循環(huán)。

Their dwindling body weight undermines their chances of surviving Arctic winters without food, the scientists added.

科學(xué)家補充道，因為體重不斷下降，北極熊在沒有食物的情況下熬過北極冬天的幾率降低了。

"The bears face an ever longer fasting period before the ice refreezes and they can head back out to feed," Steven Amstrup, who conceived the study and is chief scientist of Polar Bears International, told AFP.

該研究的提出者、北極熊國際協(xié)會的首席科學(xué)家斯蒂芬·阿姆斯特拉普告訴法新社說：“在冰雪重新凍結(jié)、可以外出覓食前，北極熊面臨著前所未有的超長禁食期。”

On current trends, the study concluded, polar bears in 12 of 13 subpopulations analyzed will have been decimated within 80 years by the galloping pace of change in the Arctic, which is warming three times as fast as the planet as a whole.

該研究得出結(jié)論稱，按照目前的趨勢，隨著北極加速變暖，研究分析的13個北極熊亞種群將有12個在80年內(nèi)滅絕。目前北極變暖速度是地球整體的三倍。

"By 2100, recruitment" — new births — "will be severely compromised or impossible everywhere except perhaps in the Queen Elizabeth Island subpopulation," in Canada's Arctic Archipelago, said Amstrup.

阿姆斯特拉普稱，“到2100年，新生北極熊數(shù)量將會劇減甚至降為零，除了(加拿大北極群島的)伊麗莎白女王群島的亞種群之外”。

That scenario foresees Earth's average surface temperature rising 3.3 degrees Celsius above the preindustrial benchmark. One degree of warming so far has triggered a crescendo of heatwaves, droughts and superstorms made more destructive by rising seas.

科學(xué)家預(yù)測，到那時地球的平均表面溫度將比工業(yè)化前基準水平高出3.3攝氏度。變暖1度迄今為止已經(jīng)引發(fā)日益嚴重的熱浪、干旱和超級風(fēng)暴，而海平面上升使得風(fēng)暴更具破壞力。

But even if humanity were able to cap global warming at 2.4 degrees Celsius — about half-a-degree above Paris Agreement targets, but hugely ambitious all the same — it would probably only delay the polar bears' collapse.

但即使人類可以將全球變暖控制在2.4攝氏度以內(nèi)——比巴黎協(xié)定目標大約高出0.5度，但也是極為雄心勃勃的計劃——這也很可能只會將北極熊滅絕的時間往后推遲一點。

The threat is not rising temperatures per se but the top-of-the-food-chain predators' inability to adapt to a rapidly shifting environment.

威脅不是來自氣溫升高本身，而是源自北極熊無法適應(yīng)快速變化的環(huán)境。

Half of Earth's land-based megafauna are classified as threatened with extinction, but only polar bears are endangered primarily by climate change.

地球上有一半的陸地巨型動物被歸類為瀕危物種，但只有北極熊主要是因為氣候變化而瀕臨滅絕。

But that status may not be unique for long, and should be seen as a harbinger of how climate will impact other animals in the coming decades, the authors warned.

研究報告的作者們警告稱，但是北極熊也許不會長期獨自處于這種境地，而應(yīng)被視為預(yù)示著未來數(shù)十年氣候?qū)⑷绾斡绊懫渌麆游锏囊粋€先驅(qū)者。

The polar bear's "vulnerable" status on the IUCN Red List of endangered species — less severe than "endangered" or "critically endangered" — does not accurately reflect their plight, the authors argue.

北極熊在國際自然保護聯(lián)盟的瀕危物種紅色名單上屬于“脆弱”等級——沒有“瀕危”或“極危”那么嚴重，研究作者指出，這一等級沒有準確反映出它們的困境。

Categories established by the International Union for the Conservation of Nature are based mainly on threats such as poaching and habitat encroachment that can be addressed with local action on the ground.

國際自然保護聯(lián)盟設(shè)立的等級主要基于偷獵和棲息地破壞等威脅，這些都可以通過當(dāng)?shù)匦袆觼斫鉀Q。

"But we cannot build a fence to protect sea ice from rising temperatures," said Amstrup.

阿姆斯特拉普說：“但我們無法建起圍欄來保護海冰不受氣溫升高的影響。”