Division of Hydrologic Sciences, Desert Research Institute, Reno, NV 89512;
Division of Hydrologic Sciences, Desert Research Institute, Reno, NV 89512.
Proc Natl Acad Sci U S A. 2019 Jul 23;116(30):14910-14915. doi: 10.1073/pnas.1904515116. Epub 2019 Jul 8.
Lead pollution in Arctic ice reflects large-scale historical changes in midlatitude industrial activities such as ancient lead/silver production and recent fossil fuel burning. Here we used measurements in a broad array of 13 accurately dated ice cores from Greenland and Severnaya Zemlya to document spatial and temporal changes in Arctic lead pollution from 200 BCE to 2010 CE, with interpretation focused on 500 to 2010 CE. Atmospheric transport modeling indicates that Arctic lead pollution was primarily from European emissions before the 19th-century Industrial Revolution. Temporal variability was surprisingly similar across the large swath of the Arctic represented by the array, with 250- to 300-fold increases in lead pollution observed from the Early Middle Ages to the 1970s industrial peak. Superimposed on these exponential changes were pronounced, multiannual to multidecadal variations, marked by increases coincident with exploitation of new mining regions, improved technologies, and periods of economic prosperity; and decreases coincident with climate disruptions, famines, major wars, and plagues. Results suggest substantial overall growth in lead/silver mining and smelting emissions-and so silver production-from the Early through High Middle Ages, particularly in northern Europe, with lower growth during the Late Middle Ages into the Early Modern Period. Near the end of the second plague pandemic (1348 to ∼1700 CE), lead pollution increased sharply through the Industrial Revolution. North American and European pollution abatement policies have reduced Arctic lead pollution by >80% since the 1970s, but recent levels remain ∼60-fold higher than at the start of the Middle Ages.
北极冰中的铅污染反映了中纬度地区工业活动的大规模历史变化，如古代铅/银生产和最近的化石燃料燃烧。在这里，我们使用来自格陵兰和Severnaya Zemlya 的广泛的 13 个精确测年的冰芯中的测量结果，记录了从公元前 200 年到公元 2010 年北极铅污染的时空变化，重点解释了公元 500 年至 2010 年的情况。大气传输模型表明，北极铅污染主要来自 19 世纪工业革命前的欧洲排放。数组所代表的大范围北极地区的时间变化非常相似，从早期中世纪到 20 世纪 70 年代工业高峰期，铅污染增加了 250 至 300 倍。在这些指数变化之上，还存在明显的多年至数十年的变化，这些变化与新采矿区的开发、技术改进和经济繁荣时期的增加有关；与气候干扰、饥荒、重大战争和瘟疫有关的减少。结果表明，从中世纪早期到中世纪晚期，尤其是在北欧，铅/银开采和冶炼排放以及银产量都有了大幅增长，而在中世纪晚期到近代早期，增长速度较低。在第二次鼠疫大流行（公元 1348 年至约 1700 年）接近尾声时，铅污染在工业革命期间急剧增加。自 20 世纪 70 年代以来，北美和欧洲的污染减排政策已经将北极铅污染减少了>80%，但最近的水平仍比中世纪初高出约 60 倍。
