Mid-twentieth century increases in anthropogenic Pb, Cd and Cu in central Asia set in hemispheric perspective using Tien Shan ice core

A first-of-its-kind multi-decadal ice core record from the Inilchek Glacier in the Tien Shan reveals significant mid-twentieth century increases in anthropogenic lead (Pb), cadmium (Cd), and copper (Cu) concentrations, reflecting large-scale Soviet industrial and agricultural expansion. The study, spanning 1908–1995 AD, demonstrates that these pollutants surged by factors of up to 5, 6, and 3 relative to pre-1950 levels, with primary sources traced to southern Kazakhstan and the Fergana Valley. Declines in the 1980s coincided with Soviet economic downturns, but resurgent trends in the 1990s indicated a shift to western China as the dominant emission source, highlighting regional and hemispheric-scale pollutant transitions. High-resolution trace element analysis, combined with back-trajectory modeling (NOAA HYSPLIT), provided unprecedented insights into anthropogenic pollution dynamics in central Asia.

Grigholm, B., Mayewski, P. A., Aizen, V., Kreutz, K., Wake, C. P., Aizen, E., Kang, S., Maasch, K. A., Handley, M. J., & Sneed, S. B. (2016). Mid-twentieth century increases in anthropogenic Pb, Cd and Cu in central Asia set in hemispheric perspective using Tien Shan ice core. Atmospheric Environment, 131, 17–28. https://doi.org/10.1016/j.atmosenv.2016.01.030