#AGU16 NOAA’s releases their annual Arctic Report Card

Today at the AGU convention in San Francisco, NOAA’s NSIDC released their annual Arctic report card, which I copy below without comment. In a story released by AP, NSIDC’s director Mark Serreze said:

“Personally, I would have to say that this last year has been the most extreme year for the Arctic that I have ever seen,” said Mark Serreze, director of the National Snow and Ice Data Center in Boulder, Colorado, who wasn’t part of the 106-page report. “It’s crazy.”

At least he’s off the “death-spiral” talk. From NOAA’s Arctic Program:


Persistent warming trend and loss of sea ice are triggering extensive Arctic changes.

Observations in 2016 showed a continuation of long-term Arctic warming trends which reveals the interdependency of physical and biological Arctic systems, contributing to a growing recognition that the Arctic is an integral part of the globe, and increasing the need for comprehensive communication of Arctic change to diverse user audiences.

Highlights:

  • The average surface air temperature for the year ending September 2016 is by far the highest since 1900, and new monthly record highs were recorded for January, February, October and November 2016.
  • After only modest changes from 2013-2015, minimum sea ice extent at the end of summer 2016 tied with 2007 for the second lowest in the satellite record, which started in 1979.
  • Spring snow cover extent in the North American Arctic was the lowest in the satellite record, which started in 1967.
  • In 37 years of Greenland ice sheet observations, only one year had earlier onset of spring melting than 2016.
  • The Arctic Ocean is especially prone to ocean acidification, due to water temperatures that are colder than those further south.  The short Arctic food chain leaves Arctic marine ecosystems vulnerable to ocean acidification events.
  • Thawing permafrost releases carbon into the atmosphere, whereas greening tundra absorbs atmospheric carbon.  Overall, tundra is presently releasing net carbon into the atmosphere.
  • Small Arctic mammals, such as shrews, and their parasites, serve as indicators for present and historical environmental variability. Newly acquired parasites indicate northward sifts of sub-Arctic species and increases in Arctic biodiversity.

Video:

The report:

Executive Summary

2016 Addendum

Full PDF here

Source: http://www.arctic.noaa.gov/Report-Card

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111 thoughts on “#AGU16 NOAA’s releases their annual Arctic Report Card

  1. I suspect that this assessment could have also been delivered back in the late 1800’s when the artic was last accessible due ice cap reduction.
    IMHO the whole issue is due to humans inability to easily comprehend time scales beyond our immediate lifetimes. The first cavemen were probably astounded that the sea was going away the first time they saw the tide recede. Oh the calamity! Then magically the sea came back. We’re merely observing long term cyclical phenomena and are extrapolating doom based upon the current slope of the change.

    • The slope is not just one way. There has been a significant change the Arctic since the first OMG event in 2007 when the “death spiral” stopped spiralling.


      https://judithcurry.com/2016/09/18/is-the-arctic-sea-ice-spiral-of-death-dead/

      This years OMG ice extent was the same level and the 2007 OMG ice extent: that’s no net change after ten years of “WTF it’s all melting away”.

      This inconvenient truth seems to have escaped the notice of hundreds of “climate experts” who spend their working lives getting in a flap about the need for better “communication”.

    • A recent collection of all available data going back to the 1850s shows that what you state is not the case.

      The sea ice extent, volume etc is now lower than at any time since 1950

      • Then obviously, before 1950, sea ice extent was lower than at present. In other words, current sea ice extent is neither unprecedented, nor outside the range of natural variation.

      • Since 1950? Wow, that’s amazing, you mean to tell me there are ebbs and flows in sea ice extent over time?

      • 1850 Tom

        and of course it ebbs and increases: in the 1930s and 40s it was lower, mostly on the Russian side…

        but the lowest then, probably 1942, was a much greater extent than anything we see now (probably to a high degree of certainty not as low as 2007)

      • Griff, you have no idea what you are talking about. The present warm spell did not get started until 1970 but all observations of this Arctic warming start bin the middle seventies or later. Going back two millennia there was nothing much that happened in the Arctic except for slow and linear cooling until the turn of the twentieth century. Then, a sudden and inexplicable warming set in. It lasted until 1940 when a cold spell arrived and wiped it out. This cold lasted only thirty years, from 1940 to 1970, and then a warming, again started, suddenly and miraculously. But none of the present observers of Arctic warming know about this because they did not start observing until the warming was already under way. And, yes, do you have any idea how such a warming gets turned on and off like that? These guys think it was done by carbon dioxide, the usual scapegoat for global warming. I hate to tell you, but it is entirely impossible for carbon dioxide to suddenly start a warming after two thousand years of cooling. Or to decide to turn off warming for thirty years or so and then again turn it up . I bet you don’t know any more about it than those guys do. Let me now tell you a secret: it has nothing to do with carbon dioxide — the mysterious warmth comes from the Gulf Stream. Here is the connection. At the turn of the twentieth century, the North Atlantic current system was re-organized such that the Gulf Stream, which previously had followed the East Coast north and then spread out into the North Sea, was redirected so that a large part of it entered the Arctic Ocean directly. The source of this secret you will find in E&E, volume 22, issue 8 in 2011. Read pages 1069 nto 1083 and educate yourself about the Arctic.

    • The more you scrutinize something that wasn’t really scrutinized to the same level before, you’re going to see things that seem alarming, but have really been happening all along.

  2. The section about Surface air temperature:
    http://www.arctic.noaa.gov/Report-Card/Report-Card-2016/ArtMID/5022/ArticleID/271/Surface-Air-Temperature
    refers to stations north of 60 latitude. But of course we don’t know which stations these are, we don’t see the data for these individual stations, and we don’t know what adjustments were made. I suspect there are no stations out over the ice or the ocean, and the ones over land (mostly below 70 latitude) are heavily adjusted.
    In other words, the graph of surface temperatures is mostly due to data created to fill in the huge void, and is estimated from created (adjusted) data along the fringe of the arctic. So it’s a complete fabrication.

      • Thanks for this overview of stations in the study. To me, it looks like they include stations along the Norwegian coastline which measure the temperture in the Gulf stream passing northwards, into the Barents Sea. Why are there no stations on Svalbard and northern Greenland – too cold, I presume…

      • Martin, more precisely the stations measure air temperature 1 meter above the land surface. Likely the absolute temperature on the coast is moderated by the ocean, compared to inland. The study was looking at long term warming trends, so interannual and even decadal effects were not the focus. Interesting that the Norway stations showed annual trends similar to the others, but many of them reported cooling January trends, in contrast to the others.

    • “. I suspect there are no stations out over the ice or the ocean, and the ones over land (mostly below 70 latitude) are heavily adjusted.”

      You would be wrong

      • Steven, a recent discussion here revealed as few as 11 weather stations north of 70* and none north of 80*.

        At risk of introducing a fact into your argument, please identify a station out over the ice or the ocean. Or were you just driving by?

    • Surface observations in the Arctic are supported by satellite measurements of the lower troposphere. UAH satellite covers 60-90 deg north. Jan-Nov 2016 has been by far the warmest Jan-Nov period on record in that region. It’s currently 1.30C above the 1981-2010 average. The next warmest Jan-Nov period in 60-90N was 0.79C, set in 2010.

      In order for the Arctic ‘not’ to set a new warmest annual record in UAH this year, the December anomaly would need to be around -5.0C. Given that the previous record November low was around 5 times smaller than that, a new warmest year in the Arctic looks nailed on in UAH.

      UAH values are available here (see ‘NoPol’ column): http://www.nsstc.uah.edu/data/msu/v6.0/tlt/uahncdc_lt_6.0.txt

      • “In order for the Arctic ‘not’ to set a new warmest annual record in UAH this year, the December anomaly would need to be around -5.0C. Given that the previous record November low was around 5 times smaller than that, a new warmest year in the Arctic looks nailed on in UAH.”

        Warmest during a VERY short record. how was it 1000 years ago? 2000? We don’t know. so we can’t say, with any confidence, that anything happening now is unprecedented in any meaningful way.

      • Jeff Alberts

        I was just making the point that recent satellite data supports the surface observations of unusually warm temperatures across the Arctic this year. Others here have suggested that this was an artefact of poor spatial coverage on the surface, or dodgy data extrapolation, or both. Apparently not.

  3. “has been the most extreme year for the Arctic that I have ever seen,””

    NO…… the most extreme years were through the LIA and the late 1970’s.

    • Those years were extreme in what way?

      Can you explain why we now see such continued low extent and volume or point to another year in the arctic outside the satellite record with such low ice levels?

      • Why do you like cold weather? What’s the correct temp for the arctic and why. Also, why isn’t that Antarctic cooperative?

      • I don’t like the cold any more or less than other people, and of course there is no ideal level: it changes over geologic time.

        I am merely pointing out a clear trend of decline in sea ice, with an exceptional and unseasonal low …

        This is a clear indication of a warming climate… the changes are too great and have gone on too long to be considered weather.

        If you aren’t concerned about that, perhaps you should be.

    • What record?

      https://www.carbonbrief.org/how-greenland-ice-sheet-fared-2016

      “Despite the temporary “cold cap” and higher-than-average snowfall over the previous winter – approximately 576 Gt between 1 September 2015 and 4 June 2016 – the warmer than average temperatures and high melt rates meant there was still slightly less ice on Greenland’s surface at the end of the melt season than usual.

      It is important to bear in mind that the “surface mass balance” technique for assessing the ice sheet refers to the amount of snow and ice that accumulates and melts each year. This only accounts for about two-thirds of the losses from the ice sheet.

      Given that it doesn’t include the remaining third of ice that is lost through calving icebergs and ocean melting, it is usually strongly positive at the end of the year. 2016 was no exception – gaining around 247bn tonnes of new ice. This is just below the average of about 290bn tonnes.

      Once the rate of calving icebergs and ocean driven melting is factored in, the total mass balance will almost certainly be negative – that is, more ice lost than snowfall gained. Since 2003 the GRACE satellite mission has shown a consistent overall net loss of ice from Greenland each year. Figures covering summer 2016 will likely be available in October or November.”

  4. I get really annoyed when so-called scientists substitute Carbon for Carbon Dioxide, is the idiot talking about Soot or the essential to life trace gas CO2 which is not REMOTELY LIKE CARBON. As I am fond of saying, if the great scientists so hate Carbon then I am happy for them to deposit all of it on my front lawn – with one stipulation, it has to be in the solid tetrahedral bonded crystalline form.

    • Amen.

      The minute I hear someone use the word “carbon” instead of “carbon dioxide” I immediately discount everything else they have to say.

      • “Same with “ocean acidification”. Either of the two phrases and you can discount the rest as being propaganda (or fake news).”

        The local Seattle news mentioned some initiative or something, and mentioned ocean acidification. They said the world’s oceans are 30% more acidic than they were before the Industrial Revolution. no context provided, no mention that the oceans aren’t even close to being acidic. You can call it “fake news”, I call it total dishonesty.

  5. This is like a report card that instead of listing grades, gives a prediction of your child’s career and predicts your child’s health throughout life based upon the past semester.

  6. We just experienced the warmest November ever with temperatures up slightly above the long term normal – That’s clearly climate change. Now North America is experiencing a super cold December with temperature 10 to 15 degrees below normal. Well – That’s just weather!
    (Sarc off)

    • The cold is displaced from the arctic because of the changes in the arctic vortex themselves caused by climate change.

      Back to the arctic: any explanation from you of the continued, exceptional low ice levels?

      would you care to predict that next year or any year in the next decade will see a recovery to pre 2007 levels?

      • Griff … you keep polishing that turd of the arctic vortex being unique because of climate change while ignoring all the past arctic outbreaks (the original term) which have always happened during Northern Hemisphere winters.

      • From Griff
        “The cold is displaced from the arctic because of the changes in the arctic vortex themselves caused by climate change.”

        This is pure opinion not backed up by anything other than theory and speculation, yet you say it as though it was fact.

      • “…continued, exceptional low ice levels?”

        Based on the assorted graphs I see on climate4you, 2007 and 2012 had lower minimums and there is nothing “exceptional” about the current level. Looks well within natural variations. Could all be part of a 100 – 200 year cycle and nobody would even know.

      • Tell me why I should care about sea ice. Polar bears don’t really need it. They’ve adapted to take advantage of it if it’s there, but they do fine without it.

      • Stewart and PB

        Back at you…

        You seem determined to divert discussion from the actual exceptional conditions in the arctic…

        This level of anomaly for temps and the ice at this season is exceptional, isn’t it?

        and you are unwilling to accept that or offer any explanation as to the current state of things…

      • Total BS Griff, we had the polar vortex displacement in the 60s and 70s, before climate change. It used to be called the Polar Express.

  7. Typo on opening screen of the Arctic ice report. The ship’s name should be Академик Шокальский (Akademik Shokalskiy) of recent Antarctic (in)fame.

    The Wiki article from which the Russian Cyrillic name was copied has a sanitized version of what actually occurred.

    No more than 400 ppm of \sarc here.

  8. The video is a mix of facts and conjecture, the sombre mood set by the monotone narrator, sad and resolute as if predicating the end of times. I missed alot laughing at stuff like “corrosive oceans” as if salt is not corrosive but a pH that drops into the neutral range is. Clearly it’s a piece of propaganda meant to indoctrinate an uneducated mind.

    • That’s why they have to control the school system. Like the Hitler jugend get them when they are young. It was the Indoctrinated Fanatic Hitlerjugend who were fighting until the bitter end for a better world.

  9. “Even small amounts of human-derived carbon dioxide (CO2) can cause significant chemical changes that other areas do not experience.” (From the “Executive Summary”)
    Human derived CO2 is much more powerful than the other kinds?

    • There you have it:
      Pure magical thinking and absurd reasoning by people who claim to be scientists… OMG!

      BTW: In the Arctic we have 24 h polar night at the moment. This means, the greater area of sea water without insulation by sea ice will cool more now by radiating more heat into space. And the lower albedo of open water is not important at all, without any sunshine at the moment. This way, nature does remove extra warmth from the last El Nino years in its own effective way…

    • How much CO2 is in the oceans? How much is in the atmosphere? A small amount in the atmosphere isn’t even detectable in the oceans.

    • No, it is not a good thing. They are speaking of invasive species. Biodiversity is good only in the case of illegal immigrants invading from across the border to take jobs away from citizens or to acts of terrorism committed by devotees of the religion of peace.

  10. “The average surface air temperature for the year ending September 2016 is by far the highest since 1900, and new monthly record highs were recorded for January, February, October and November 2016 …”.
    =======================================================
    The statement is simply untrue, at least according to HadCRUT4:

    Diagram showing area weighted Arctic (70-90oN) monthly surface air temperature anomalies (HadCRUT4) since January 1920 (climate4you).

    • I suspect the area weighting is biasing that chart. HadCRUT4 used very few Arctic stations in the early years of the record and those that it did use tended to be lower latitude and land based. It does not infill gaps in its spatial data. Water surface readings would only have been available in summer, for instance.

      So I think that by applying area weighting whoever made that chart is effectively spreading mostly relatively low latitude and therefore warmer temperatures across a much wider area, where temperatures were bound to have been cooler.

      GISS infills regions with missing data and its Arctic record shows that, while there was a spike in Arctic temperatures during the 1930s and 1940s, modern temperatures are around a degree C warmer than they were back then: http://oi63.tinypic.com/2cy2ujq.jpg

      • “I suspect the area weighting is biasing that chart.”

        I suspect that presenting a single line for an average of recorded temp locations is biasing that chart. It’s also physically meaningless. Intensive properties.

    • What data did we have about temperatures above 70 N? There was at that time virtually nothing there other than a few native Inuit (or whatever they are in Russia) camps. Everything before about 1965 is complete guess work filling in between 4 or 5 observation stations. This is Science?

    • Don’t understand – why does the “year ending September 2016” include October and November 2016 ???

  11. Arctic sea ice volume, area and extent are all at record lows for the date for the satellite period from ’79.

  12. Just imagine a mayfly walking on a bumpy broom handle that extends from earth to the moon, and you get some idea of the narrow perspective of the people reporting these ice trends.

    A mayfly has a lifespan of about a day.

  13. Al Gore’s new movie bodes for a cold winter, a Limerick.

    The Sundance Film Festival will be held January 19 – 29 in Park City, Utah with a new climate change movie from Al Gore yet to be named — and the timing could not be better, it coincides with the Presidential inauguration. Whenever there is a meeting on climate change, In Copenhagen, jn Cancoun, Washington, D.C or wherever, it seems to be unusually cold. This film festival has an environmental theme, so the Polar Vortex is here to last.

    Al Gore was the champion of hype

    Catastrophe fear was his gripe

    CO2, it is bad

    we’ll all die, we’ve been had.

    The Grinch, not the Santa Claus type. https://lenbilen.com/2016/12/13/al-gores-new-movie-bodes-for-a-cold-winter-a-limerick/

  14. “The Arctic Ocean is especially prone to ocean acidification, due to water temperatures that are colder than those further south.”

  15. Because cold water takes up more CO2. Seems to be if it gets warmer it will become more alkaline. Compare Tropic surface to Arctic waters.

  16. I keep hearing about ‘record temps’ here in oz (in the south, north is coolish, 25C in the tropics in summer) these days. Reading the artickes tells you that we haven’t seen temps this high for x years, typically 100 years. That tells me these are not record temps at all, it was just as hot 100 years ago! Fake news, perhaps?

    • Well there are certainly record temps in the arctic, which is the subject of this article, that’s indisputable, as is the documenting of the continued decline in sea ice, continued melt on Greenland, etc.

      for which there is no explanation other than global warming.

      • I expect they experience higher temperatures and the effects of higher temps, Philip.

        There is also much less ice than in any previous recent cycle, isn’t there?

      • So Grif, was AGW the cause of an ice free N Pole as recorded in the logs of Norwegian Navy vessels visiting the pole in the very early 1800’s? These logs are archived by the Norwegian Navy and can be viewed.
        Also, was AGW the cause of very thin ice at the North Pole when the US Nave atomic submarine USS Skate surfaced at the pole on 11 Aug 1958? Photos of the event can be found by googling the event and it can be clearly seen that the ice is about one foot thick. Is this thin? Thick? Medium?
        You cannot state that the decline in Arctic sea ice is caused by global warming as you do not have complete detailed understanding of the world climate mechanisms. Nobody does. You are simply making an assertion. Assertions are not proofs.
        Brian J in UK.

      • Brian

        I have never seen a record of Norwegian vessels at an ice free pole.
        Please post a reference

        Stress in pack ice opens up temporary leads and holes/thin ice/Polnyas…

        A nuclear submarine can use sonar to find an ice spot thin enough to punch through, with luck and care.

        The ice was however generally thicker then – the skipper of the Skate records ridges up to 150 foot thick in his memoirs…

        Next year you might well see open water from the Russian coast to the Pole… which any vessel could sail across. That will be a step different from finding an isolated, temporary thin patch.

        and yes, science has a good understanding of world climate mechanisms.

      • Griff,
        You state that “science has a good understanding of world climate mechanisms”. How come then that all the predictions of the effects of increasing CO2 in the atmosphere have simply not happened, despite the steady increase in the amount of CO2? Eg: pause in global temperature increase for 20 yrs? No hot spot in the middle atmospheric levels? Predicted Antarctic warming absent? etc etc. One would have thought that the direct consequence of this “good understanding of world climate mechanisms” would have by now led to accurate predictions and – incidentally – a reduction in the amount of taxpayers money now needing to be spent on AGW research. Since we now know everything (!) what’s still to find out?
        I cant find the book in which I read of the Norwegian Navy logs so I cannot give a reference. I apologise for making a statement I could not provide a reference for. However in a paper L. Polyak, et al, “History of Sea Ice in the Arctic”, Quarterly Science Reviews, 29 (2010) pp 1757 – 1778, there is a graph on page 1759 showing the decline in the minimum level of ice at the N Pole, 1860 to 2010. This clearly shows that the steep decline started ~ 1945 and has continued at the same rate since then – the slope of the line is unchanged, 1945 to 2010. So how does this show increasing atmospheric CO2 is responsible – since all agree that the big growth of the man made production of CO2 started ~ 1970 – when the global average temperature started to rise? What accounted for the sudden steepening of the curve ~ 1945?
        My apologies for not being able to reproduce the graph here, but you can Google it.
        B rgds, Brian J in UK.

  17. Re carbon – buckminsterfullerine is rather fun. Gigatonnes of carbon in the atmosphere are falling on my lawn as buckyballs. It’s a miracle!

    • I do love well presented and accurate data, that’s true…

      Not so keen on bad news for ecosystems/the planet at any season

      • Again, explain why sea ice is important at all. And no mention of Polar Bears, they do fine with or without.

      • https://nsidc.org/cryosphere/quickfacts/seaice.html

        “Why is Arctic sea ice important?

        Arctic sea ice keeps the polar regions cool and helps moderate global climate. Sea ice has a bright surface; 80 percent of the sunlight that strikes it is reflected back into space. As sea ice melts in the summer, it exposes the dark ocean surface. Instead of reflecting 80 percent of the sunlight, the ocean absorbs 90 percent of the sunlight. The oceans heat up, and Arctic temperatures rise further.

        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. This is consisistent with observations of a warming Arctic. The loss of sea ice also has the potential to accelerate global warming trends and to change climate patterns.

        For more on the ways sea ice interacts with other Earth systems, including global ocean circulation, people, and animals, see ”

        https://nsidc.org/cryosphere/seaice/environment/index.html

      • “The loss of sea ice also has the potential to accelerate global warming trends and to change climate patterns.”

        Except we haven’t seen anything like that. Also, ocean temperatures have nothing to do with human CO2 emissions.

  18. Warming is welcome in the Arctic. It’s too cold in Greenland, Siberia, Alaska and northern Canada. Ice free Arctic ocean is good for navigation. Sailors don’t want to get stuck in ice and the Eskimo want to farm in Greenland.

    • Well the Inuit sure as heck won’t be hunting seals if this goes on… I am not sure they want to turn to farming though.

      Tell me, an ice free arctic: surely that would have some further impact on the world’s climate? Changed albedo at least?

      • “Tell me, an ice free arctic: surely that would have some further impact on the world’s climate? Changed albedo at least?”

        Maybe, maybe not. But there’s no evidence that it will be catastrophic in any way. There’s also no evidence that what we’re seeing is unprecedented on geologic time scales. Forget about your short, myopic view of a couple of decades and short term trends (short meaning less than 1000 years).

        A few years ago, much of the nothern hemisphere was covered with snow. That albedo change would be orders of magnitude higher than just the arctic. Yet nothing catastrophic occurred.

      • It is a situation we haven’t seen since the early Holocene, that’s for sure.

        If it has any effect, that’s a cause for concern… we don’t even have to go to ‘severe effect’ or your ‘catastrophic’ hyperbole

      • It is a situation we haven’t seen since the early Holocene, that’s for sure.

        We don’t know that for sure. That’s the whole problem. It most likely has, and much more recently than the early Holocene, but we don’t know for sure one way or the other. But you’re admitting that it’s happened in recent geologic history. So, not unprecedented. Good.

        If it has any effect, that’s a cause for concern… we don’t even have to go to ‘severe effect’ or your ‘catastrophic’ hyperbole

        If it’s not severe or catastrophic, then why is it a cause for concern? It’s happened before, as you said. We’ll adapt, as we always have.

  19. “The average surface air temperature for the year ending September 2016 is by far the highest since 1900, and new monthly record highs were recorded for January, February, October and November 2016.”
    Have you noticed that the “high” temperatures were in the winter months, when the temperature anyway is far below freezing? The ice does not melt because the temperature is -15C instead of -25C, but the average yearly temperature could change a lot.

    • Hey, it has been zero C or even just above as the storm systems have come through…

      and the ice has melted in November on the Atlantic side, due to warm ocean temperatures, also this month in Bering strait, again due to warm ocean temps…

      and the ice extent is a record low and it isn’t forming or is forming over a month late in many areas.

  20. We have a comparison of snapshot measurements of a short term cycle, riding on a medium term cycle, imposed on a long term cycle. The equivalent of measuring the temperature change from 10:00 AM to 2:00PM, and extrapolating it to the next month, without factoring the daily change in temperature, and the seasonal variation.
    We have 40 years of reasonably good Arctic data. Before that it is poor to the point of not useful. Making broad generalizations about the severity of these short term trends is just bad science. But that is what passes for analysis of “long-term Arctic warming trends”, when the agenda demands adherence to the party line.

    • That is not the case.

      Recent efforts have collated excellent data going back to 1850

      Norwegian, Danish and Soviet data exists, plus records of whaling ships, plus cold war era ice information from submarines… reams of data.

  21. Where’s the information we’re coming from 6 years El Niña doing 2 years La Niña.

    That way they can go arguing on and on!. Duh!

  22. If the ice sheet gradually breaks up, there will be smaller and smaller ice floes. As long as some of these remain, the fetch available for the wind to create waves is limited. You have all seen photos of scattered ice floes with a dead flat calm sea – quite mirror like. And ‘mirror like’ is important because the angle of the sunshine is going to be no more than 23.44 degrees on average. At 80 north, it will vary during the day from 33.44 to 13.44 degrees at mid summer. At these angles, a flat water surface is a good reflector – indeed, at even greater angles a flat water surface is a good reflector. Think when you were last flying, the reflection of the sun in rivers, streams or lakes was dazzling. So, little heat will be absorbed from the sun’s radiation. What little is absorbed will be in the top very narrow layer, and that water will evaporate, thus cooling the surface.

    In winter when the ice covers the sea, the surface is bitterly cold. In effect, the layer of ice acts as an insulator, keeping the heat from the – comparatively – warm water in the water under the ice. In summer, the insulating layer is removed, and the water can radiate heat – likely more than it receives.

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