How Maori’s Arrival in New Zealand Was Frozen in Antarctic Ice

When it comes to records of human history, don’t overlook Earth’s only uninhabited continent.

Researchers have recently found soot preserved in Antarctic ice, linked to fires in New Zealand by Māori settlers, the islands’ first human inhabitants. The team suggests that finding evidence of fires thousands of kilometers away is a dramatic example of early humanity’s environmental impact.

These results Published Wednesday in Nature.

Since the 1960s, researchers have been extracting long ice cores from Antarctica, Greenland, and other snowy regions. But ice cores, made up of layers of snow that accumulate each year and are compressed over time, contain more than just ice. They may also contain particulate matter such as soot and volcanic ash that were once in the air.

“Ice cores actually tell you what fell from the sky,” said environmental scientist Joseph McConnell of the Desert Research Institute in Reno, Nev.

By examining particulate matter in ice cores, scientists can detect past events. big fires, volcanic eruptions, and even industrial melting.

In 2008, Dr. McConnell and colleagues set out to analyze six ice cores dug in Antarctica. Working with chunks of ice, about three feet long at a time, the team melted each one and fed the resulting liquid into an instrument that turned it into aerosols. The researchers then passed these aerosol particles through a laser, which caused any soot present to heat up and glow.

Dr. “We’re measuring this incandescence,” McConnell said.

Using this technique, the researchers calculated the rate at which soot particles fell into Antarctica over the past two thousand years. They found that four of the ice cores collected from the continent Antarctica exhibited roughly constant proportions over time. But the other two ice cores, both of which had been collected James Ross Island On the North Antarctic Peninsula, it exhibited a roughly threefold increase in soot beginning in the late 13th century.

This contradiction was surprising. “What was different about the North Antarctic Peninsula?” Dr. McConnell said.

The team turned to atmospheric modeling to investigate the mystery. The researchers found that the soot that eventually settled on James Ross Island may have come from only a few places. Dr. “Because of atmospheric circulation, New Zealand, Tasmania, and Southern Patagonia fit the bill,” McConnell said.

To find the most likely source, the researchers analyzed published coal records from each of the three locations. The charcoal reveals that the woody material was burned nearby, and changes in its abundance over time can be traced, just like soot records in ice.

Only New Zealand exhibited a marked increase in coal abundance at the end of the 13th century, consistent with ice core records on the northern Antarctic Peninsula.

“We’re seeing this big peak about 700 years ago, which we call the first burning period,” said Dave McWethy, an ecologist at Montana State University who studies coal in New Zealand, and one of the study’s co-authors.

However, Dr. McWethy said it was a big surprise to find signatures of these fires thousands of kilometers away in Antarctica. “No one knew it could go this far and actually be recorded in ice cores.”

The increase in fire activity in New Zealand at the end of the 13th century is most likely linked to the arrival of the Māori. researchers suggested. Dr. McWethy said that Māori, like other Indigenous groups, use fire to make their environment more livable. “Fire is a wonderful tool for people around the world.”

Dr. McWethy said that when Māori settlers arrived, more than 90 percent of New Zealand was forested, and the burned portions of the land made it easier to travel through dense forest. “Pretty impenetrable.”

Fire would also be important for clearing land for growing taro, yam, and similar crops. gamblingNgāi Tahu, a descendant of Ngāti Māmoe and Waitaha, said Kelly Tikao, a researcher in Māori traditions at the University of Canterbury in New Zealand, who was not involved in the study. The burned parts of the landscape would not only enable agriculture but also encourage the growth of wild but edible plants. Fern Developing after the fires, Dr. Tikao said.

Dr. Tikao added that the Maori deliberately used fire, but never had the intention to destroy their sights.

“Our philosophy of who we are is based on the elements of Earth, and fire is one of them,” he said. “When you believe the land is yours, the last thing you want to do is kill it.”

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