Abstract. Our study is the first to demonstrate a high-temporal-resolution record of mineral composition in a Greenland ice core over the past 100 years. To reconstruct the past variations in the sources and transportation processes of mineral dust in northwestern Greenland, we analyzed the morphology and mineralogical composition of dust in an ice core from 1915 to 2013 using Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDS). Analysis of the SEM-EDS reveals that the ice core dust mainly consisted of silicate minerals and the composition varied substantially on multi-decadal and inter-decadal scales, suggesting that the geological origin of the ice core minerals changed periodically during the past 100 years. The multi-decadal variation trend differed among mineral types: kaolinite generally formed in low- or middle-latitude areas were abundant in the colder periods (1950 to 2000), whereas mica, chlorite, feldspars, mafic minerals, and quartzes formed in arid, high-latitude, and local areas were abundant in the warmer periods (1915 to 1949 and 2005 to 2013). This indicates that the multi-decadal variation of the relative abundance of the minerals can be attributed to the local temperature changes in Greenland. The trajectory analysis shows that the minerals were mainly transported from the western coast of Greenland in the two warming periods, which was likely due to an increase of dust sourced from local ice-free areas. On the other hand, the abundant kaolinite was likely derived from old sediments at higher latitudes in North America, rather than from low and middle latitudes.

中文翻译：

---

过去100年从格陵兰西北部获得的冰芯中尘埃矿物学的变化

摘要。我们的研究首次证明了过去100年来格陵兰岛冰芯中矿物成分的高时间分辨率记录。为了重建格陵兰西北部矿尘的来源和运输过程的过去变化，我们使用扫描电子显微镜（SEM）和能量色散X射线光谱分析了1915年至2013年冰芯中尘埃的形态和矿物学组成（EDS）。对SEM-EDS的分析表明，冰芯粉尘主要由硅酸盐矿物组成，其组成在十年和年代际尺度上都有很大变化，这表明在过去100年中，冰芯矿物的地质成因周期性变化。不同矿物类型的年代际变化趋势有所不同：通常在低纬度或中纬度地区形成的高岭石在较冷的时期（1950年至2000年）丰富，而在干旱，高纬度和局部地区形成的云母，绿泥石，长石，黑铁矿矿物和石英则丰富。温暖的时期（1915年至1949年以及2005年至2013年）。这表明，矿物相对丰度的年代际变化可以归因于格陵兰岛的局部温度变化。轨迹分析表明，在两个变暖期，矿物主要从格陵兰岛的西海岸运出，这很可能是由于当地无冰地区的粉尘增加所致。另一方面，丰富的高岭石很可能来自北美较高纬度的旧沉积物，而不是来自中低纬度。