The New Zealand Herald

Worrying signs from the Arctic

Report: Permafrost, water warming at alarming rates

- Seth Borenstein — AP

Water is warming and sea ice is melting at the fastest pace in 1500 years at the top of the world, according to a report released yesterday.

The annual report by the United States’ National Oceanic and Atmospheri­c Administra­tion (NOAA) also showed the permafrost in the Arctic is thawing at a faster rate than previously thought.

The report showed slightly less warming in many measuremen­ts than a record hot 2016. But scientists remain concerned because the far northern region is warming twice as fast as the rest of the globe and has reached a level of warming that’s unpreceden­ted in modern times.

Jeremy Mathis, head of NOAA’s Arctic research programme and coauthor of the 93-page report said “2017 continued to show us we are on this deepening trend where the Arctic is a very different place than it was even a decade ago”.

Findings were discussed at the American Geophysica­l Union meeting in New Orleans.

“What happens in the Arctic doesn’t stay in the Arctic; it affects the rest of the planet,” said acting NOAA chief Timothy Gallaudet. “The Arctic has huge influence on the world at large.”

Permafrost is the permanentl­y frozen layer below the Earth’s surface in frigid areas. Records show the frozen ground that many buildings, roads and pipelines are built on Arctic sea ice is melting at the fastest pace in 1500 years, a new survey says. reached record warm temperatur­es last year nearing and sometimes exceeding the thawing point. That could make them vulnerable when the ground melts and shifts, the report said. Unlike other readings, permafrost data tend to lag a year.

Preliminar­y reports from the US and Canada this year showed permafrost temperatur­es are “again the warmest for all sites” measured in North America, said study co-author Vladimir Romanovsky, a professor at the University of Alaska in Fairbanks.

Arctic sea ice usually shrinks in September and this year it was only the eighth lowest on record for the melting season. But scientists said they were most concerned about what happens in the winter — especially March — when sea ice is supposed to be building to its highest levels.

Arctic winter sea ice maximum levels in 2017 were the smallest they’ve ever been for the season when ice normally grows.

It was the third straight year of

What happens in the Arctic doesn’t stay in the Arctic; it affects the rest of the planet. The Arctic has huge influence on the world at large. Timothy Gallaudet

record low winter sea ice recovery. Records go back to 1979.

About 79 per cent of the Arctic sea ice is thin and only a year old. In 1985, 45 per cent of the sea ice in the Arctic was thick, older ice, said NOAA Arctic scientist Emily Osborne.

New research looking into the Arctic’s past using ice cores, fossils, corals and shells as stand-ins for temperatur­e measuremen­ts show that Arctic ocean temperatur­es are rising and sea ice levels are falling at rates not seen in the 1500 years. And those dramatic changes coincide with the large increase in carbon dioxide levels in the air from the burning of oil, gas and coal, the report said.

This isn’t just a concern for the few people who live north of the Arctic Circle. Changes in the Arctic can alter fish supply.

And more ice-free Arctic summers can lead to countries competing to exploit new areas for resources. Research also shows changes in Arctic sea ice and temperatur­e can alter the jet stream, which is a major factor in the weather.

This is probably partly responsibl­e for the current unusual weather in the United States that brought destructiv­e wildfires to California and a sharp cold snap to the south and east, according to NOAA scientist James Overland and private meteorolog­ist expert Judah Cohen.

“The Arctic has traditiona­lly been the refrigerat­or to the planet, but the door of the refrigerat­or has been left open,” Mathis said.

Outside scientists report card.

“Overall, the new data fit with the long-term trends, showing the clear evidence of warming causing major changes,” in the Arctic, said Pennsylvan­ia State University ice scientist Richard Alley. praised the

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Picture / AP

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