Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Stay on top of the latest market trends

Subscribe to Axios Markets for the latest market trends and economic insights. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Illustration: Aïda Amer/Axios

Forecasts of a grim future ahead from extreme weather have been at once so vague and frequent as to numb many people as to what's coming. But it turns out that this is the second incidence in history of climate change at least partly induced by humans.

Driving the news: In the first, a half-millennium ago, humans made the Earth cooler, which contributed to famine, disease, and popular uprisings in Europe, experts say. In much-discussed new research, U.K. scientists say the 16th century exploration of the Americas by Europeans led to a cascade of disaster.

The toll included:

  • The deaths of some 55 million native people to pandemic disease over less than a century, representing 90% of the inhabitants of North and South America — and 10% of the world population.
  • A reforestation of their now-fallow farms, covering a combined area about the size of France, causing a massive and sustained amount of carbon to be sucked from the atmosphere.
  • A consequent deepening of the so-called Little Ice Age, when temperatures plunged in Europe and across the globe. Among popular uprisings were mob violence in Ireland and a resurgence of witchcraft trials.

Why it matters: The research, from four scholars at University College London, suggests that European contact with the Americas starting with Columbus had an impact on a vast scale — shifting human and Earth history.

"It caused about half of the cold snap in the 17th century that caused all kinds of havoc all over the world," Charles Mann, author of "1493: Uncovering the New World that Columbus Created," tells Axios.

  • Thought bubble from Andrew Freedman, author of Axios' Science newsletter: "Assuming the new study is correct, it indicates that the era of human-engineering of the climate system started much earlier than the Industrial Revolution."
  • "It also suggests that the discussions about the task before us — slowing, halting and reversing global warming — may be too focused on high-tech carbon removal technologies. Planting trees and maintaining healthy forests might deserve a higher place on the priority list for carbon removal, the study suggests."

The linkage of the post-Columbus human disaster and climate cooling remains controversial, though it's accepted by an increasing number of mainstream experts, and the paper has gotten some pushback.

  • "The paper is thought-provoking, but it gives a certainty about this relationship that is not justified," says Dagomar Degroot, a professor at Georgetown, who says he has taught the theory for three or four years.
  • "I don't want to say the article is wrong or not interesting. ... [But] you can't isolate things to America without a clear sense of what was happening globally. We don't have that yet. A lot of scholarship is still in flux," Degroot tells Axios.

The research follows up on pioneering research by William Ruddiman, an emeritus professor at the University of Virginia. Since the early 2000s, Ruddiman has argued that humans began to alter the climate as soon as they organized farming 5,000 to 8,000 years ago.

  • Andrew Koch, lead co-author of the paper, tells Axios the research was meant to pull together and rationalize all of the research by Ruddiman and others, including the carbon record from ice cores pulled from Antarctica. "No one had really reviewed all of it," Koch said.
  • Ruddiman, reached at home in Virginia, said he was a peer reviewer of the paper and that he had only one quibble, which the authors handled in a footnote. It was on the amount of acreage taken up by farms and burning, which Ruddiman said was actually much larger.

The results vastly increase popular notions of how many people inhabited the New World at the time Europeans arrived: There were about 60 million people, requiring the cultivation of a little over 1 hectare of land each, or a total of about 60 million hectares.

  • "The cessation of farming doubled the cooling of the Little Ice Age," said Mark Maslin, a professor at University College London and a co-author both of the paper and a new book, "Human Planet: How We Created the Anthropocene."

Go deeper

Mike Allen, author of AM
3 hours ago - Politics & Policy

Biden adviser Cedric Richmond sees first-term progress on reparations

Illustration: "Axios on HBO"

White House senior adviser Cedric Richmond told "Axios on HBO" that it's "doable" for President Biden to make first-term progress on breaking down barriers for people of color, while Congress studies reparations for slavery.

Why it matters: Biden said on the campaign trail that he supports creation of a commission to study and develop proposals for reparations — direct payments for African-Americans.

Cyber CEO: Next war will hit regular Americans online

Any future real-world conflict between the United States and an adversary like China or Russia will have direct impacts on regular Americans because of the risk of cyber attack, Kevin Mandia, CEO of cybersecurity company FireEye, tells "Axios on HBO."

What they're saying: "The next conflict where the gloves come off in cyber, the American citizen will be dragged into it, whether they want to be or not. Period."

Cedric Richmond: We won't wait on GOP for "insufficient" stimulus

Top Biden adviser Cedric Richmond told "Axios on HBO" the White House believes it has bipartisan support for a stimulus bill outside the Beltway.

  • "If our choice is to wait and go bipartisan with an insufficient package, we are not going to do that."

The big picture: The bill will likely undergo an overhaul in the Senate after House Democrats narrowly passed a stimulus bill this weekend, reports Axios' Kadia Goba.