Tropical glaciers have retreated alongside warming temperatures over the past century, yet the way in which these trends fit into a long-term geological context is largely unclear. Here, we present reconstructions of Holocene glacier extents relative to today from the Quelccaya ice cap (Peru) and the Rwenzori Mountains (Uganda) based on measurements of in situ¹⁴C and ¹⁰Be from recently exposed bedrock. Ice-extent histories are similar at both sites and suggest that ice was generally smaller than today during the first half of the Holocene and larger than today for most, if not all, of the past several millennia. The similar glaciation history in South America and Africa suggests that large-scale warming followed by cooling of the tropics during the late Holocene primarily drove ice extent, rather than regional changes in precipitation. Our results also imply that recent tropical ice retreat is anomalous in a multimillennial context.

中文翻译：

---

南美和非洲热带地区类似的全新世冰期历史

在过去的一个世纪中，热带冰川随着温度的升高而退缩，但是这些趋势如何适应长期的地质背景却还不清楚。在这里，我们根据实地¹⁴ C和^10的测量值，提出了从Quelccaya冰盖（秘鲁）和Rwenzori山（乌干达）相对于今天的全新世冰川范围的重建来自最近暴露的基岩。在这两个地点，冰的扩散历史相似，这表明在全新世上半年，冰的体积通常小于今天，而在过去的几千年中，即使不是全部，冰也比今天的要大。南美和非洲类似的冰期历史表明，在全新世晚期，大规模的变暖继而使热带地区降温，这主要是导致冰量的扩大，而不是降水的区域变化。我们的结果还暗示，在几千年的背景下，最近的热带冰消退是异常的。