Graphic: Climate Change Institute

Global Warming in the Arctic: A Sensitive Climate Gone Off the Rails

, senior analyst, Climate & Energy Program | November 21, 2016, 4:08 pm EST
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It is polar night in the Arctic—a darkness that lasts from early October to early March. Temperatures rarely escape freezing in that darkness, averaging -30° F until the light begins to return in spring. Right now, however, temperatures across much of the Arctic are 36 degrees F above normal. Large areas are well above freezing. And instead of rapidly expanding, sea ice extent is in decline.

Taken together, this is not unusual. It’s unheard of.

The degree to which current Arctic conditions are straying from the norm may prove to be the greatest change yet measured there—the latest signal from the Arctic that all is not well.

And while the frozen top of the world may seem remote and unimportant at the moment, what happens there matters greatly to both our immediate and long-term future.

80th-parallel-meant_2016

2016 temperatures (Kelvin) above Latitude 80. The green line shows daily mean historic average temperatures from 1958-2002. The red line shows the daily mean average from 2010 to present. The blue line is 32 degrees F, or freezing. Recent days have seen departures from the long-term average of up to 36 degrees F. At and above this latitude, roughly days 1-45 and days 300-365 are spent in darkness. Source: Danish Meteorological Institute

Breaking down the Arctic breakdown

The Arctic plays an important role in moderating global climate. When heat from the tropics is delivered north to the Arctic by winds and ocean currents, the region exerts a cooling effect on both. Without this distribution of energy, the lower latitudes would overheat. Sea ice and snow- and ice-covered land (known as the “cryosphere”) help the Arctic to stay cool by reflecting most of the incoming solar energy back to space.

But the Arctic, like the rest of the planet, is warming, and unlike the rest of the planet, warming in the Arctic can feed rapidly on itself.

To describe one of the feedbacks: Warmer temperatures drive greater melt of sea ice, which exposes open ocean, and exposed water absorbs heat from sun that was previously reflected. Ocean temperatures rise as a result, and when winter comes, the sea ice has a harder time rebounding amidst warmer air and water temperatures. The following year, the melt season begins with sea ice cover that is thinner and smaller in extent.

There are other feedbacks, and all are complex. For a closer look at these reinforcing cycles, see my colleague’s blog on Why the Arctic Matters. As the National Snow and Ice Data Center puts it:

A small temperature increase at the poles leads to still greater warming over time, making the poles the most sensitive regions to climate change on Earth. According to scientific measurements, both the thickness and extent of summer sea ice in the Arctic have shown a dramatic decline over the past thirty years. […] The loss of sea ice also has the potential to accelerate global warming trends and to change climate patterns.

Okay. With this in mind, let’s look at the state of the Arctic at this time.

Sea ice extent

In the polar night, Arctic sea ice historically rebounds from summer melt as both the water and air cool. In recent decades, the ice has been declining in both extent and volume.

This year, with warm ocean temperatures and continued delivery of warm air from the lower latitudes, the ice is struggling to rebound. October saw new record lows for Arctic sea ice extent.

sea-ice-use-this-one

Global sea ice extent began 2016 (thick red line) at low levels. Just in recent days , the Arctic has lost more than a million square kilometers of sea ice, reaching a new record low and contributing to a steep decline in November’s total global sea ice extent. Antarctic sea ice extent is also at record low levels.  Source: Arctic News

In November, Arctic sea ice extent remains well below average for this time of year. In each of the last three days, a time of year when sea ice is normally growing, it has shrunk instead (see figure below). Arctic sea ice is melting up there in the polar darkness.

According to experts following this closely, as of Sunday, November 20, Arctic sea ice is now ~1.1 million square kilometers below the previous record low.

Sea surface temperatures

With larger areas of the Arctic ice-free each year, and for longer periods of time, the Arctic Ocean is absorbing more heat.

This fall, sea surface temperatures are well above average, with anomalous warmth persisting into November as seen in the figure below. Scientists have reported ocean temperatures 25° F above average in some locations.

ssts

Sea surface temperatures are unusually high and well above freezing in some areas of the Arctic, contributing to ice melt. Credit: Climate Change Institute

Air temperatures

The chart below looks at this warmth by a different measure: “freezing degree days.” By many available measures, the oncoming Arctic winter is in a nose dive unprecedented in recent record keeping.

A weakened polar vortex and wobbly jet stream have been identified as factors in recent anomalous winters, both colder and warmer, and indeed, meandering winds are currently delivering warm air far northward to the Arctic, and a deep, snowy freeze in Eurasia.

The combination of factors driving Arctic air temperatures today has resulted in a stunning temperature anomaly—persistent, vast areas of 36° F above normal, shown in the map below.

arctic-temp-anomaly-sunday

The exceptional Arctic temperature anomaly. Source: Climate Change Institute

Wild cards, like the unusual cyclone that struck the Arctic last winter, driving temperatures 50 degrees above normal, may compound and accelerate ice loss, according to a recent NASA study.

It’s as if the Arctic is trying to be heard.  It’s hard to imagine stronger signals to send.

Meanwhile, in la-la land

Meanwhile, around Latitude 39, Myron Ebell—one of the world’s most prominent and vocal climate change deniers—has been tasked with overseeing the transition of the nation’s Environmental Protection Agency. The very agency tasked with implementing the nation’s leading plan for curbing global warming pollution—the Clean Power Plan.

And Stephen Bannon—a man who oversaw, as chief of Breitbart News Agency, the disparaging of climate scientists and their overwhelming body of science—has assumed the role of chief strategist for the new administration. A role in which he can advise the new president on whether the US continues to reduce its global warming emissions or reverses course—matters vital to the future of everyone.

And today, Steven Groves of the Heritage Foundation was named to lead president-elect Trump’s State Department transition. Groves penned, just last week, an article advocating a speedy withdrawal from the the UN Framework Convention on Climate Change, to which we’ve been a party since its ratification in 1992. It’s a move that would scrap our commitments under the landmark Paris Climate Agreement—you know, that thing that stands between us and catastrophic warming.

File this under irony. No, madness.

bering_sea_sunset_-_noaa

The sun sets on the Bering Sea. Photo: NOAA

 

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  • Philip Bruce Heywood

    SCIENCEDAILY October 20, 2008
    Source:
    Geological Survey of Norway
    Summary:
    Recent mapping of a number of raised beach ridges on the north coast of Greenland suggests that the ice cover in the Arctic Ocean was greatly reduced some 6000-7000 years ago. The Arctic Ocean may have been periodically ice free.
    ”The climate in the northern regions has never been milder since the last Ice Age than it was about 6000-7000 years ago. We still don’t know whether the Arctic Ocean was completely ice free, but there was more open water in the area north of Greenland than there is today,” says Astrid Lyså, a geologist and researcher at the Geological Survey of Norway (NGU).
    Shore features
    Together with her NGU colleague, Eiliv Larsen, she has worked on the north coast of Greenland with a group of scientists from the University of Copenhagen, mapping sea-level changes and studying a number of shore features. She has also collected samples of driftwood that originated from Siberia or Alaska and had these dated, and has collected shells and microfossils from shore sediments.
    ”The architecture of a sandy shore depends partly on whether wave activity or pack ice has influenced its formation. Beach ridges, which are generally distinct, very long, broad features running parallel to the shoreline, form when there is wave activity and occasional storms. This requires periodically open water,” Astrid Lyså explains.
    Pack-ice ridges which form when drift ice is pressed onto the seashore piling up shore sediments that lie in its path, have a completely different character. They are generally shorter, narrower and more irregular in shape.
    Open sea
    ”The beach ridges which we have had dated to about 6000-7000 years ago were shaped by wave activity,” says Astrid Lyså. They are located at the mouth of Independence Fjord in North Greenland, on an open, flat plain facing directly onto the Arctic Ocean. Today, drift ice forms a continuous cover from the land here.
    Astrid Lyså says that such old beach formations require that the sea all the way to the North Pole was periodically ice free for a long time.
    ”This stands in sharp contrast to the present-day situation where only ridges piled up by pack ice are being formed,” she says.
    However, the scientists are very careful about drawing parallels with the present-day trend in the Arctic Ocean where the cover of sea ice seems to be decreasing.
    “Changes that took place 6000-7000 years ago were controlled by other climatic forces than those which seem to dominate today,” Astrid Lyså believes. End SCIENCEDAILY extract.

    A quick glance at ice core graphs suggests atmospheric carbon 6 – 7 thou. yrs ago significantly LOWER THAN TODAY’S LEVEL.

  • solodoctor

    Alarming, to say the least. So, what does UCS intend to do in the coming months and years about these anti-science people living in la la land who will be advising our next President?!? What can we UCS members do to help with these efforts?

  • rrjames

    The major consequence to us of the warming described above is methane entering our atmosphere.

    https://www.youtube.com/watch?v=O854kS0-AYw&t=4931s