The chronology of the most extensive Late Pleistocene glaciation in the eastern Pyrenees is now well established, but climatic variations during the subsequent Last Glacial-to-Interglacial Transition (LGIT) are much less well documented. The aim of this research is to fill that gap. We present a new series of 22 ¹⁰Be exposure ages from a sequence of moraines in the upper Ariège catchment, and update 64 previously published exposure ages from seven other valleys. Based on (i) geomorphological maps of successive generations of ice-marginal deposits and (ii) their age distributions, followed by (iii) glaciological modeling to infer corresponding mass-balance gradients and equilibrium line altitudes (ELAs), we reconstruct glacier behaviour in the eastern Pyrenees during the LGIT and retrieve paleoclimatic parameters for each glacial stillstand. Results document rapid deglaciation involving four relative stillstands, with an ELA rise of ∼410 m and increases in temperature and precipitation of ∼4 °C and ∼40%, respectively, between ∼18 ka (Greenland Stadial GS-2.1b) and ∼14.5 ka (Greenland Interstadial GI-1). A cold and dry environment prevailed from ∼18 ka onward, and deglaciation was almost complete by GI-1. Only small glaciers persisted as late as ∼12.3 ka in cirques where local conditions allowed it. These patterns are compatible with a transient Polar Front Jet Stream repositioning to latitudes of 40–42°N between 18 and 16 ka, with Westerlies-dominated circulation not yet feeding precipitation to the mountain belt abundantly from the northwest, and outbursts of polar air meeting with cool sea waters in the western Mediterranean mostly suppressing precipitation from Mediterranean sources.

在比利牛斯山脉东部，最晚更新世冰川形成的年代学已经很成熟，但是随后的上一次冰期至冰期间过渡（LGIT）期间的气候变化则文献记载得很少。这项研究的目的是填补这一空白。我们提出了一个新的系列22 ¹⁰从上游阿里耶格流域的一系列冰rain中获取暴露年龄，并更新其他七个山谷中先前发布的64个暴露年龄。基于（i）连续几代冰缘沉积物的地貌图和（ii）它们的年龄分布，然后（iii）进行冰川学建模以推断出相应的质量平衡梯度和平衡线高度（ELA），我们重建了LGIT期间位于比利牛斯山脉东部，并为每个冰川静止地带检索古气候参数。结果记录了涉及四个相对静止台的快速冰消作用，ELA上升了约410 m，温度和降水分别在约18 ka（格陵兰Stadial GS-2.1b）和约14.5之间上升了约4°C和约40％。 ka（格陵兰星际GI-1）。从〜18 ka开始，寒冷和干燥的环境盛行，GI-1几乎完成了冰消作用。在当地条件允许的情况下，只有小冰川在约12.3 ka之前持续存在于圆形冰山中。这些模式与瞬态极地前喷流兼容，该极流在18至16 ka之间重新定位到40–42°N的纬度，而Westerlies主导的环流尚未从西北向山地提供大量降水，并且极地空气汇流爆发地中海西部的凉爽海水主要抑制了地中海来源的降水。