The Arctic sea ice max for this winter was second lowest on record, thanks in part to an “extreme heat wave”

By Tom Yulsman | March 23, 2018 1:40 pm

The maximum extent of sea ice after a winter of growth was well below average — an area of lost ice about two-thirds the size of Alaska

Arctic sea ice extent on March 17, compared to the long-term median. (Source: NSIDC)

Arctic sea ice extent on March 17, compared to the long-term median. (Source: NSIDC)

After expanding all winter, the Arctic’s floating lid of sea ice has now reached its maximum extent — and it has continued an unsettling trend.

The National Snow and Ice Data Center announced today that this year’s maximum extent is the second lowest in the 39-year record of satellite observations.

“The four lowest maximum extents in the satellite record have all occurred in the past four years,” according to the NSIDC. Last year set the record for the very lowest.

Arctic sea ice appears to have maxed out this year on March 17, with an extent that was 448,000 square miles below the long-term median. That area of lost ice would cover about two thirds of Alaska.

Autumn freeze up occurred late this year, particularly in the Chukchi Sea off Alaska. This occurred in part because of large amounts of ocean heat being transported into the area through the Bering Strait.

In addition to the delayed freeze-up, air temperatures were persistently high in the Arctic, helping to retard ice growth. And February brought “an extreme heat wave over the Arctic Ocean,” according to the NSIDC.

In the dead of winter, warm air from the south surged across the Arctic toward the North Pole, bringing temperatures that soared to, and possibly above, the freezing mark. “This is the fourth winter in a row that such heat waves have been recorded over the Arctic Ocean,” the NSIDC says.

recent study shows that these winter heat waves are becoming more frequent and intense.

  • Mike Richardson

    The findings from NSIDC illustrate the strengths of satellite remote sensing technology in showing the increasingly obvious signs of a warming planet. While there may be some dispute over temperature data derived from remote sensing, due to the fact that the data must be processed in a more complex manner than direct temperature readings taken at the surface, it’s much more difficult to dispute the loss of ice or rising sea levels. In the cases of both sea ice and sea levels, there is clear evidence of long-term trends resulting from climate change.

    • With Respect

      Sadly, at the same time we’re losing valuable scientific ship-based, land-based, and now that there’s so little of the stable stuff left ice-based observations.

      The more interest there is in increasingly valuable climate data, the harder governments cut away, deliberately blinding our scientists when we need them most. If it weren’t for the value of satellite data to logistics, those too would be shut down, it appears.

      • Mike Richardson

        Yes, and the common refrain now is that NASA shouldn’t be involved in Earth monitoring, since NOAA does that (even as NOAA’s budget is cut). Meanwhile, land based measurements get criticized as archaic by folks who don’t understand that the measurements on the ground can be more accurate than the satellites, and can complement the greater coverage provided by remote sensing technology. But the people making those arguments have no interest in seeing the knowledge pool expanded, as they prefer to hide behind a protective veil of willful ignorance. We need more and better information regarding the effects of climate change, so that an informed public can make better decisions on how to deal with it.

    • Damn Nitpicker

      ❝increasingly obvious signs of a warming planet❞

      Evidence of warming does not implicate a cause of the warming.

      • Mike Richardson

        The cause is known, though you choose not to acknowledge it.

        • Damn Nitpicker

          Lots of people are ‘convinced’ of the cause. I clamoured for evidence. I was directed to the US National … uh, climate change report … something like that. In there, the authors babbled on about “multiple lines of evidence” … but the reasoning was circular. Shepherd, T, 2014: ”The accepted evidence of anthropogenic climate change is based on multiple global indicators of change including surface temperature, upper-ocean heat content, sea level, Arctic sea-ice extent, glaciers, Northern Hemisphere snow cover, large-scale precipitation patterns (especially as reflected in ocean salinity), and temperature extremes (Figure 1a,b). All these global indicators are physically linked in a direct way to the first on the list, surface temperature, and the changes are robust in observations, theory, and models 1.”
          See, “warming” is but one item … not many, and not independent. Warming is just a symptom.
          Trenberth, Fasullo, & Balmaseda 2014: ”“Warming” really means heating and extra energy, and hence it can be manifested in many ways. Rising surface temperatures are just one manifestation. Melting Arctic sea ice is another.”
          von Schuckmann 2016: ”…global temperature rise, increased [ocean heat content], sea level rise, and the acceleration of the hydrological cycle (Fig. 2b). These are all symptoms of [Earth’s energy imbalance].”
          So, two or three pages of the US National …whatever … and not a bit of actual evidence. Nothing to indicate the cause … which you say, is known. What’s the evidence (and don’t suggest warming or other manifestations of warming!)

          • Mike Richardson

            The cause is CO2 and other greenhouse gases emitted by human activity. There’s a pretty good explanation of that here:

            I suggest actually reading the article and checking the provided links to sources, though I suspect you’ll dismiss it all as not providing the particular “evidence” you demand, like the “uh, climate change report… something like that.” Now that doesn’t sound much like someone making a real effort at comprehending and recalling what they’ve read. Your recent posting history arguing with practically every side in this debate, as well as your chosen user name, suggests you are simply trolling for the sake of stirring others up and getting attention. I’ve seen individuals with much more experience at that than you come and go here, and I’m pretty tired of humoring that type. So on that note, this will be the last time I play this game with you. You should probably go find someone else to attempt to annoy, or better yet, get a new hobby altogether.

          • Damn Nitpicker

            Fine – bow out. As you were going out, while I am demanding evidence, you point me to a blog? Sounds like you don’t have the answer I’m looking for, either. See ya.

        • Damn Nitpicker

          ❝The cause is known, though you choose not to acknowledge it.❞

          Well, while looking for other things, I re-read this paper by Judith Lean. She answered my question. I’ve been looking for observational evidence; her paragraph, rather succinctly, says that the only evidence is that from the computer models.

          Lean 2018: ”The Fourth Assessment Report (AR4) of the IPCC (2007), charged with the detection and attribution of climate change for its Government stakeholders, stated that ❝Most of the observed increase in global average temperature since the mid‐20th century is very likely due to the observed increase in anthropogenic greenhouse gases❞. The basis for asserting a discernible human influence on climate is statistical comparisons of observed temperature with physical model simulations of the changes expected from anthropogenic and natural influences (Hegerl & Zwiers, 2011; Stott et al., 2010).”

          There is no physical, observational evidence.



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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