Dronning Maud Land 沿海冰芯中低频 δ¹⁸O 变率的来源
Sources of low-frequency $δ^{18}$O variability in coastal ice cores from Dronning Maud Land
AI总结：
本文利用多锥谱、奇异谱分析和 Liang-Kleeman 信息传递率，研究了 Dronning Maud Land 两个邻近冰芯 δ¹⁸O 的低频变率，揭示了 ENSO、PDO、SAM、DMI、海冰面积及 AMO 等气候驱动因子的不同因果影响与局地差异。
摘要：
利用多锥谱方法和奇异谱分析，对最近在 Dronning Maud Land（南极洲）两个不同地点钻取的冰芯（FK17 和 TIR18）中记录的 δ¹⁸O 低频变率进行了研究。这些记录中出现了多个主导周期峰，周期在 3 至 20 年之间。尽管两个地点在空间上相对接近（相距约 100 公里），但它们显示出不同的谱特征，表明在这两个地点产生变率的过程不同。为了阐明哪些过程在这两个位置对 δ¹⁸O 起作用，使用一种因果方法（即 Liang-Kleeman 信息传递率）研究了若干气候指数以及海冰面积的影响。对来自外部源的低频变率起源的分析表明，El Niño-Southern Oscillation（ENSO）、Pacific Decadal Oscillation（PDO）、Southern Annular Mode（SAM）、Dipole Mode Index（DMI）和海冰面积对 FK17 的 δ¹⁸O 显示出重要的因果影响。对于 TIR18，主要影响来自 ENSO、PDO、DMI、海冰面积和 Atlantic Multidecadal Oscillation（AMO），揭示了 Dronning Maud Land 相互作用的复杂性。这两个地点共享若干驱动因子，但也显示出可能与海洋邻近性和气团轨迹差异有关的局地特异性。本文讨论了这些发现对两个冰芯中低频变率的意义。
英文摘要：
The low-frequency variability of the $δ^{18}$O recorded in ice cores (FK17 and TIR18) recently drilled at two different locations in Dronning Maud Land (Antarctica), is investigated using multi-taper spectral method and singular spectrum analysis. Multiple dominant peaks emerge in these records with periods between 3 and 20 years. The two sites show distinct spectral signatures, despite their relative proximity in space (about 100 km apart), suggesting that different processes are involved in generating the variability at these two sites. In order to clarify which processes are acting on $δ^{18}$O at these two locations, the impact of several climate indices as well as sea ice area is investigated using a causal method, known as the Liang-Kleeman rate of information transfer. The analysis of the origin of this low-frequency variability from external sources reveals that El Niño-Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), the Southern Annular Mode (SAM), the Dipole Mode Index (DMI) and the sea ice area display important causal influences on $δ^{18}$O at FK17. For TIR18, the main influences are from ENSO, PDO, DMI, the sea ice area, and the Atlantic Multidecadal Oscillation (AMO), revealing the complexity of the interactions in Dronning Maud Land. The two locations share several drivers, but also show local specificities potentially linked to ocean proximity and differences in air mass trajectories. The implication of these findings on the low-frequency variability in the two ice cores is discussed.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
