Lead, sulphate, and aluminium concentrations and lead crustal enrichment factors in Mt. Logan ice core during pre-anthropogenic to modern periods

A high-resolution, 8000 year-long ice core record from the Mt. Logan summit plateau (5300 m asl) reveals the initiation of trans-Pacific lead (Pb) pollution by ca. 1730, and a >10-fold increase in Pb concentration (1981-1998 mean = 68.9 ng/l) above natural background (5.6 ng/l) attributed to rising anthropogenic Pb emissions from Asia. The largest rise in North Pacific Pb pollution from 1970-1998 (end of record) is contemporaneous with a decrease in Eurasian and North American Pb pollution as documented in ice core records from Greenland, Devon Island, and the European Alps. The distinct Pb pollution history in the North Pacific is interpreted to result from the later industrialization and less stringent abatement measures in Asia compared to North America and Eurasia. The Mt. Logan record shows evidence for both a rising Pb emissions signal from Asia and a trans-Pacific transport efficiency signal related to the strength of the Aleutian Low.

这项采自洛根山（Mt. Logan）峰顶高原（海拔5300米，asl）的高分辨率、长达8000年的冰芯记录显示，跨太平洋铅（Pb）污染的起始时间约为1730年；铅浓度较自然本底值（5.6 ng/l）升高10倍以上，1981-1998年的铅浓度均值为68.9纳克每升（ng/l），这一现象可归因于亚洲人为铅排放的持续攀升。1970年至本记录截止的1998年期间，北太平洋铅污染出现最为显著的上升，这与格陵兰、德文岛及阿尔卑斯山脉冰芯记录中所记载的欧亚与北美铅污染下降态势完全同步；北太平洋地区之所以呈现独特的铅污染历史，被认为是相较于北美与欧亚地区，亚洲工业化起步更晚、减排管控措施更为宽松所致。洛根山冰芯记录同时展现出两类信号的证据：一是源自亚洲的铅排放强度上升信号，二是与阿留申低压（Aleutian Low）强度相关的跨太平洋传输效率信号。