You just knew without reading all the way to the end, that the editors insisted the authors find someway to placate the current political gods of “climate change” to explain some prime findings.
Why? To promote the current alarmism about “climate change”,
What is clear from how “climate change” is referenced in this story and how such references are used by the alarmists?
What is clear is that even if you accepted “climate change” as a prime factor in the “abrupt” end (probably took place over the course of a thousand years) of native North American copper mining, it has very little alarm to it for humans today, because what the natives of 9,000 to 5,000 years ago lacked was the advanced state of human knowledge and technology today, that makes possible human adaptation to, and mitigation of, whatever “climate change” throws at us.
Did they blame the Climate Change of Olde on mankind as well?
Smelting, mining, industrial waste!