来源：《新科学家》
原文刊登日期：2021年11月24日
本文适合2023考生
Salty Atlantic waters may have been seeping into the Arctic since the early 20th century, several decades earlier than previously believed. The Arctic is warming faster than any other part of the world and the increasing influence of water from the Atlantic Ocean, which is on average warmer and saltier than the Arctic Ocean, is likely to be leading to further ice loss.
自20世纪初以来，大西洋咸水可能已经渗入北极，比以前认为的要早几十年。北极的变暖速度比世界上任何其他地区都快，而大西洋的水的影响越来越大，平均而言，大西洋比北冰洋更温暖、更咸，这可能会导致冰的进一步流失。
This effect is known as “Atlantification”, says Tesi Tommaso at the Italian National Research Council Institute of Polar Sciences. But it is hard to quantify because we only have 20 years of confirmed data about the interaction between these waters, he adds.
意大利国家极地科学研究委员会的托马索说，这种效应被称为“大西洋化”。但这很难量化，因为我们只有20年关于这些水域之间相互作用的确定数据，他补充道。
He and his colleagues studied the Fram Strait in the Arctic Ocean between Greenland and the Norwegian Svalbard ilands. They collected a 112-centimetre deposit core from the bottom of one of Svalbard’s inlets to reconstruct the history of the strait.
他和他的同事们研究了位于格陵兰岛和挪威斯瓦尔巴群岛之间的北冰洋的弗拉姆海峡。他们从斯瓦尔巴特群岛的一个海湾底部收集了一个112厘米厚的沉积物岩芯，以重建该海峡的历史。
“The rock is in the ocean,” says Tommaso. “What we see is a reflection of the water’s properties.” The layers of the core correspond to deposits laid down over the past 800 years, which hold clues to the time they were deposited. “Every centimetre gave us climate information for about four to five years,” says Tommaso.
“岩石在海里，”托马索说。“我们看到的是水性质的反映。”岩心的岩层与过去800年的沉积相对应，其中包含了它们沉积时间的线索。托马索说：“每一厘米都为我们提供了大约四到五年的气候信息。”
The team found that for the earliest 700 years or so, nothing changed in the composition of organic matter in the deposit. But in samples corresponding to the year 1907, they saw a sudden change in the oxygen isotopes in the organic matter. “This change suggests the waters became a lot warmer and saltier,” says Tommaso.
研究小组发现，在最早的700年左右的时间里，沉积物中有机物的组成没有任何变化。但在对应年份为1907年的样本中，他们发现有机物中的氧同位素发生了突然的变化。托马索说：“这种变化表明海水温度变高，盐度增大。”
The team is unsure what caused this dramatic shift in temperature. “It could be a natural event that propagated from the subpolar regions to the gate of the Arctic Ocean,” says Tommaso. More data and modelling are needed to gain a clearer picture of what caused this sudden change, he says.
研究小组还不确定是什么导致了温度的急剧变化。托马索说:“这可能是一个自然事件，从北极以南地区传播到北冰洋的门户。”他说，需要更多的数据和模型来更清楚地了解是什么导致了这种突然的变化。
“This early Atlantification is important as it will have pre-conditioned the Arctic to be susceptible to the more rapid change seen today,” says Yueng-Djern Lenn at Bangor University, UK.
英国班戈大学的Yueng-Djern说：“早期的大西洋化是重要的，因为它将使北极预先适应今天看到的更快速的变化。”
Understanding the history of this effect can tell us about how the ecosystem may respond in the future, says Marie Porter at the Scottish Association for Marine Science. “The process of Atlantification continues across the Atlantic-Arctic under post-industrialisation climate change.”
苏格兰海洋科学协会的玛丽·波特说，了解这种影响的历史可以告诉我们未来的生态系统可能如何反应。“在后工业化时代的气候变化下，大西洋-北极地区的大西洋化进程仍在继续。”