Little Ice Age

A story that’s been making the rounds:

Genocide of Native Americans by European settlers was cause of Little Ice Age

The upheavals following the first contact with Europeans in 1492 is thought to have cut the population of 60 million living across the Americas down to five or six million within just 100 years

The “Little Ice Age” of the 16th and 17th centuries was triggered by the genocide of indigenous people in the Americas by European settlers, new research suggests.

Scientists have long wondered what caused the drop in temperatures so severe that it caused the River Thames to freeze over.

New analysis by University College London (UCL) argues that so many people were slaughtered or died of disease that the amount of agricultural land dramatically reduced, which in turn sucked carbon dioxide (CO2) from the atmosphere.

Known as the “Great Dying,” the upheavals following the first contact with Europeans in 1492 is thought to have cut the population of 60 million living across the Americas down to five or six million within just 100 years. Published in Quaternary Science Reviews, the study found that much of the land previously cultivated by indigenous civilizations would have fallen into disuse, becoming swallowed up by forest and grassland.

It estimates that an area of 56 million hectares, roughly the size of modern-day France, would have been “rewilded” in this way.

The scale of the change is believed to have drawn an amount of CO2 from the atmosphere equivalent to two years of fossil fuel emissions at the present rate.

Professor Mark Maslin, from UCL’s School of Geography, said: “There is a marked cooling around that time which is called the Little Ice Age, and what’s interesting is that we can see natural processes giving a bit of cooling, but to actually get the full cooling – double the natural processes – you have to have this genocide–generated drop in CO2.”

The research team examined historical population data, using it to model the reduction of land devoted to agriculture.

Ed Hawkins, professor of climate science at Reading University, said: “Scientists understand that the so-called Little Ice Age was caused by several factors – a drop in atmospheric carbon dioxide levels, a series of large volcanic eruptions, changes in land use and a temporary decline in solar activity. The drop in CO2 is itself partly due the settlement of the Americas and the resulting collapse of the indigenous population.

“It demonstrates that human activities affected the climate well before the industrial revolution began.”

An interesting theory! But I have some questions. How many Native Americans actually practiced agriculture? And why do cultivated crops put more CO2 into the atmosphere than wild flora? This quite apart from the immense difficulty of determining past population numbers in the absence of a proper census. It would have been good for the article to cite actual data (from ice cores, etc.) about just how much atmospheric carbon dioxide declined in the Early Modern Period.

But as is so often the case with newspaper articles, you have to read all the way to the end to get the real story (which is why I have taken the liberty of reproducing the entire piece). Prof. Hawkins says something completely commonsensical – that the LIA was caused by a variety of factors, only one of which was the decline of atmospheric CO2. Thus the headline, that “genocide” “caused” the Little Ice Age, seems completely overstated, in the usual journalistic fashion.

Younger Dryas and Gobekli Tepe

Interesting new theory: a comet killed off the wooly mammoth – and impelled the rise of civilization!

Experts at the University of Edinburgh analysed mysterious symbols carved onto stone pillars at Gobekli Tepe in southern Turkey, to find out if they could be linked to constellations.

The markings suggest that a swarm of comet fragments hit Earth at the exact same time that a mini-ice age struck, changing the entire course of human history.

Scientists have speculated for decades that a comet could be behind the sudden fall in temperature during a period known as the Younger Dryas. But recently the theory appeared to have been debunked by new dating of meteor craters in North America where the comet is thought to have struck.

However, when engineers studied animal carvings made on a pillar – known as the vulture stone – at Gobekli Tepe they discovered that the creatures were actually astronomical symbols which represented constellations and the comet.

Using a computer programme to show where the constellations would have appeared above Turkey thousands of years ago, they were able to pinpoint the comet strike to 10,950 BC, the exact time the Younger Dryas begins according to ice core data from Greenland.

The Younger Dryas is viewed as a crucial period for humanity, as it roughly coincides with the emergence of agriculture and the first Neolithic civilisations.

Before the strike, vast areas of wild wheat and barley had allowed nomadic hunters in the Middle East to establish permanent base camps. But the difficult climate conditions following the impact forced communities to come together and work out new ways of maintaining the crops, through watering and selective breeding. Thus farming began, allowing the rise of the first towns. 

Emphasis added. There’s more at the link. Gobekli Tepe has been noticed earlier on this blog.

Let it Snow

On this snow-day-that-wasn’t, a reminder from the New England Historical Society (courtesy my friend Bill Campbell), of the Great Snow of 1717 in New England:

Remembering the Great Snow of 1717 in New England

Had enough snow yet? Given the staggering Great Snow of 1717, it’s somewhat surprising that this question isn’t the official New England motto. That year, historians report that New England had probably the roughest winter it ever recorded.

So much snow fell that year, capped off by a series of storms that started in late February, that the Puritans in Boston held no church services for two successive weeks, reported Cotton Mather. The events were so unusual that he and other contemporary diarists made note of how exceptionally harsh it was throughout New Hampshire, Massachusetts and Connecticut.

Though the dates varied, the storms are most commonly cited as having occurred between February 27 and March 9, though others include storms of February 18 to the 24th as being part of the Great Snow of 1717.

Regardless of dates, for generations after it became common in New England to refer to events as having occurred either before or after the great snow. Writers including Henry David Thoreau made reference to its historical significance in their work.

Throughout the region snow totals from the back-to-back storms were recorded of four, five and six feet, with drifts as high as 25 feet. Entire houses were covered over, identifiable only by a thin curl of smoke coming out of a hole in the snow. In Hampton, N.H., search parties went out after the storms hunting for widows and elderly people at risk of freezing to death. It wasn’t uncommon for them to lose their bearings and not be able to find the houses. Sometimes they were found burning their furniture because they couldn’t get to the woodshed.

Read the whole thing.