Abstract Climate changes during the Late Glacial period (LG; 15-11 ka) as recorded in Greenland and Antarctic ice cores show a bipolar pattern. Between 14.5 ka and 13 ka ago, the northern latitudes experienced the Bolling/Allerod (BA) warm period, while southern records feature the Antarctic Cold Reversal (ACR). Between 12.9 ka and 11.7 ka ago, the north was under the Younger Dryas (YD) cold spell while southern latitude temperature rose in parallel to atmospheric CO2 concentrations. While the southern hemisphere pattern is well documented in mountain glacier moraine records from New Zealand and Patagonia, in northern mid-latitudes and the Arctic, the LG glacier culmination has been connected to the YD stadial, apparently confirming the bipolar pattern. We present a geomorphic map of mountain glaciers in Arctic Norway, a cosmogenic nuclide chronology from 71 moraine boulders from the LG and the Holocene, and first-order glacier modeling experiments. The model and dating results show that the studied mountain glaciers are most sensitive to summer-temperature change, that their response to those changes is highly correlated to a wider region and that these mountain glaciers in Arctic Norway reached their maximum LG extent about 14 ka ago, prior to the YD. Following considerable retreat through the first part of the YD, glaciers re-stabilized in the mid-YD and showed slower oscillatory retreat through the latter part of the YD. We compare this glacier pattern to updated earlier glacier records in the wider Arctic and North Atlantic region and propose a pattern of coherent glacier response to climate changes during this interval. The LG results from Arctic glaciers show consistency to the glacier record from New Zealand and Patagonia. This first-order interhemispheric coherency of LG mountain glacier fluctuations driven mainly by summer temperature would support the view that the bipolar seesaw was primarily a northern winter phenomenon during the LG period, and the YD in particular. More similar experiments need to be performed to further test this scenario.

中文翻译：

---

晚冰期山地冰川在新仙女木之前在挪威北极达到顶峰

摘要 格陵兰岛和南极冰芯记录的晚冰期 (LG; 15-11 ka) 的气候变化显示出双极模式。在 14.5 ka 和 13 ka 之前，北纬经历了 Bolling/Allerod (BA) 暖期，而南部记录则以南极冷逆转 (ACR) 为特征。在 12.9 ka 和 11.7 ka 之前，北部处于新仙女木 (YD) 寒流之下，而南部纬度温度与大气 CO2 浓度同步上升。虽然南半球模式在新西兰和巴塔哥尼亚的山地冰川冰碛记录中有详细记录，但在中纬度北部和北极，LG 冰川的顶点与 YD stadial 相连，显然证实了双极模式。我们展示了挪威北极地区山地冰川的地貌图，来自 LG 和全新世的 71 块冰碛巨石的宇宙成因核素年表，以及一级冰川建模实验。模型和测年结果表明，所研究的山地冰川对夏季温度变化最为敏感，它们对这些变化的反应与更广泛的区域高度相关，并且挪威北极的这些山地冰川在大约 14 ka 前达到了最大 LG 范围, 在 YD 之前。在通过 YD 的前半部分大量撤退之后，冰川在 YD 中期重新稳定，并在 YD 的后半部分显示出较慢的振荡后退。我们将这种冰川模式与更广泛的北极和北大西洋地区更新的早期冰川记录进行比较，并提出了在此间隔期间冰川对气候变化的连贯响应模式。北极冰川的 LG 结果与新西兰和巴塔哥尼亚的冰川记录一致。这种主要由夏季温度驱动的 LG 山地冰川波动的一阶半球间相干性将支持双极跷跷板在 LG 时期主要是北方冬季现象，尤其是 YD 的观点。需要进行更多类似的实验来进一步测试这种情况。