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Arctic’s strongest sea ice breaks up for the first time on record

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Arctic sea ice works as the planet’s air conditioner in that it keeps the polar regions cold and helps keep the global climate stable, according to the NSIDC. Sea ice has a bright white surface so that nearly 80% of the sunlight that strikes it is reflected back into space. When sea ice melts, it exposes the darker ocean surface. The dark water does not reflect solar energy but instead absorbs 90% of the sunlight while heating the ocean and causing Arctic temperatures to rise further. In climate science, this is called the albedo effect, and, it is a vicious feedback loop that should scare the bejeebus out of people.

The Arctic Ocean’s thickest and oldest sea ice is located to the north of Greenland and in the Canadian Archipelago. The seawater in this area is frozen, even in the summer. The media has reported, without mentioning climate change of course, on this freakish weather year with records that have been broken for heat waves, floods, droughts, and wildfires in the world’s temperate zones; it also broke records in the Arctic, the fastest warming region on Earth. In an ominous sign of biosphere collapse, The Guardian reports that these frozen waters have been opened up not once, but twice so far this year due to warm winds (that tear the ice from where it’s fastened at the coastal bedrock) as well as climate change driven heatwaves in the northern hemisphere. This has never happened before and prompted Thomas Lavergne, a scientist at the Norwegian Meteorological Institute in a retweet to describe the phenomenon as “scary”. As we continue to pump even more carbon from fossil fuel emissions into the atmosphere we rapidly heat the Arctic and we should count on more and more severe and unprecedented weather events.

Jonathan Watts writes in The Guardian:

Ice to the north of Greenland is usually particularly compacted due to the Transpolar Drift Stream, one of two major weather patterns that push ice from Siberia across the Arctic to the coastline, where it packs

Walt Meier, a senior research scientist at the US National Snow and Ice Data Center, said: “The ice there has nowhere else to go so it piles up. On average, it’s over four metres thick and can be piled up into ridges 20 metres thick or more. This thick, compacted ice is generally not easily moved around.

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This year’s openings are driven more by wind than melting but they have occurred during two temperature spikes. In February, the Kap Morris Jesup weather station in the region is usually below -20C (-4F), but earlier this year there were 10 days above freezing and warm winds, which unlocked the ice from the coast.

Last week, the crack opened again after Kap Morris Jesup briefly registered a record high of 17C (62.6F) and strong southerly winds picked up to 11 knots. Experts predict that coastal seas will freeze again but probably later than normal.

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Arctic sea ice is once again pulling away from the coast of far northern Greenland. You can easily see this reflected in the current drift circulation: https://t.co/BkhAkJipgm. Sea ice extent in the Greenland Sea has been at or near a record low for most of 2018. pic.twitter.com/zvOEyNpHut

— Zack Labe (@ZLabe) August 6, 2018

The shattered old and thick sea ice, along with icebergs from melting glaciers, is being funneled into the Nares and Fram straits and channeled south into the Atlantic. This is causing serious alarm for shipping and for oil rigs off of Newfoundland. 

Inside Climate News reports on the February break up:

The drifting sea ice was also studded with thousands of icebergs, most of them from Greenland's accelerating glaciers. Those rivers of ice have speeded up sharply in recent years, and the icebergs that break off of them into the ocean drift southward, where they get caught up in the drifting sea ice. The past two decades have seen the highest number of icebergs in the northwest Atlantic since at least 1900.

The pattern could persist for at least several decades, but the long-term future for icebergs is less certain, because some glaciers will retreat so far inland that they won't be able to discharge icebergs into the ocean anymore. Instead, the glaciers will terminate on land and release the melting ice as water, Bigg said.

From the AGU on the February break up.

WASHINGTON D.C. — More Arctic sea ice is entering the North Atlantic Ocean than before, making it increasingly dangerous for ships to navigate those waters in late spring, according to new research.

The new research finds ocean passages typically plugged with ice in the winter and spring are opening up. Sea ice normally locked in the Arctic then can flow freely through these passages southward to routes used by shipping, fishing and ferry boats.

The new study finds Arctic sea ice surged through these channels in 2017 and clogged normally open areas of ocean around Newfoundland in May and June. The ice cover trapped many unsuspecting ships and sunk some boats when the ice punctured their hulls.

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“It’s counterintuitive to most people, because it means you can have an increase in local ice hazards because of a changing climate in the high Arctic,” said David Barber, an Arctic climate researcher at the University of Manitoba in Winnipeg, Canada and lead author of the new study in Geophysical Research Letters, a journal of the American Geophysical Union. “This is something we need to better prepare for in the future, because we expect this phenomenon to go on for at least a couple more decades as we transition to an ice-free Arctic in the summer.”

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