Long-term winter warming trend in the Siberian Arctic during the mid- to late Holocene
Long-term winter warming trend in the Siberian Arctic during the mid- to late Holocene
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DOI：
10.1038/ngeo2349
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发表时间：
2015-02
影响因子：
18.3
通讯作者：
H. Meyer;T. Opel;T. Laepple;A. Dereviagin;Kirstin Hoffmann;M. Werner
中科院分区：
文献类型：
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作者：
H. Meyer;T. Opel;T. Laepple;A. Dereviagin;Kirstin Hoffmann;M. Werner
相对于过去的2,000年，北极地区在过去几十年里显著变暖。然而，在全新世的其余时间里，北极温度的演变还不太清楚。代用重建表明，在整个全新世中期至晚期，有长期的变冷趋势，而气候模式模拟只显示出微小的变化，甚至变暖。在这里，我们提出了一个记录的永久冻土冰楔的氧同位素组成在西伯利亚北极的勒拿河三角洲。反映冬季温度的同位素值在过去7 000年中逐渐变得更加丰富，在过去50年中达到前所未有的水平。全新世中晚期的这种变暖趋势与其他代用记录中的变冷趋势相反。然而，大多数现有的替代记录都偏向于夏季温度。我们认为，相反的趋势与季节性不同的轨道强迫在此期间。此外，我们重建的趋势，以及最近的最大值是一致的温室气体强迫和气候模式模拟，从而调和不同的估计北极和北方高纬度温度演变在全新世。
Relative to the past 2,000 years,, the Arctic region has warmed significantly over the past few decades. However, the evolution of Arctic temperatures during the rest of the Holocene is less clear. Proxy reconstructions, suggest a long-term cooling trend throughout the mid- to late Holocene,,, whereas climate model simulations show only minor changes or even warming,,. Here we present a record of the oxygen isotope composition of permafrost ice wedges from the Lena River Delta in the Siberian Arctic. The isotope values, which reflect winter season temperatures, became progressively more enriched over the past 7,000 years, reaching unprecedented levels in the past five decades. This warming trend during the mid- to late Holocene is in opposition to the cooling seen in other proxy records,,. However, most of these existing proxy records are biased towards summer temperatures. We argue that the opposing trends are related to the seasonally different orbital forcing over this interval. Furthermore, our reconstructed trend as well as the recent maximum are consistent with the greenhouse gas forcing and climate model simulations, thus reconciling differing estimates of Arctic and northern high-latitude temperature evolution during the Holocene.