Ice core records uncover widespread air pollution from early 20th-century copper production
AI Summary
Ice-core evidence indicates that air pollution from the Anaconda Copper Mine complex near Butte, Montana, spread over long distances around a century ago. Arsenic and other heavy-metal particles were carried by winds to the Arctic and deposited in ice layers, preserving a record of historic industrial pollution.
About a century ago, the Anaconda Copper Mine complex near Butte, Montana, was emitting vast amounts of air pollution into the atmosphere. As small particles of arsenic and other heavy metals were carried by winds over the Arctic, storms eventually helped pull them to the ground, where they joined layers of history embedded in the ice.