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Sea Ice Update: Unprecedented SH High, Rapid NH Recovery

There won’t be much, if any, coverage in the media about the unprecedented high in the Southern Hemisphere sea ice anomaly, so a self-explanatory graphic is posted below of the 1979 to present anomaly from the 1979 to 2000 mean:


We will, of course, be hearing about the extent of the Northern Hemisphere sea ice during the summer, which has bounced back over the winter from its record low. See the graph below of the anomaly for 1978 to present from the 1978 to 2000 mean:


I’ll finish with a graphic of the un-exciting 1979 to present global sea ice anomaly trend (in red) from the 1979 to 2000 mean (in black), and the global daily sea ice anomaly (in blue):

The graphs are from The Cryosphere Today


16 Responses to “Sea Ice Update: Unprecedented SH High, Rapid NH Recovery”

  1. Comment from: Pierre Gosselin

    If you look more closely, you’ll see the NH is not really much above last year at this time:

    As far as the SH is concerned, we’re a good million sq km ahead of last year at this time.

    But with this PDO cooling taking hold, maybe we’ll see changes in the NH trends.

  2. Comment from: Paul Biggs

    Indeed – it will be interesting to what happens to the NH sea ice this year.

  3. Comment from: Denialist Scum

    “If you look more closely, you’ll see the NH is not really much above last year at this time:”

    Keep this in perspective though — six months ago, the melting NH polar ice cap was used to generate a fresh wave of alarm and hysteria. It was supposed to herald the imminent end of life as we know it, and people were even being urged to pray for the ice caps.

    And now — in a single season — its back ABOVE where it was last year??

    etc… etc… ad infinitum …

  4. Comment from: Ian Mott

    This is all very good but we have no right to complain about any lack of publicity if we don’t convert it to an actual map showing the 1979, present day, and intervening maximum and minimum.

    We need a pretty pickie, with lots of clean white ice.

  5. Comment from: Luke

    Informed commentary last year said that this year was unlikely to fall to or below the same levels. i.e. it was exceptional.

    The trend in the NH time series is what is interesting. One year’s data does not make a trend. Indeed the current ice levels are still not even average.

    If you’re protesting at biased reporting let’s aim for some clarity here!?

    IMO – NH and SH should be reported individually not as a global total or issues will be confounded.

  6. Comment from: AB

    Indeed the NH sea ice is still clearly trending downwards for April values;

    The problem here, as i keep saying to colleagues, is that in the Arctic you have (well, had) a significant portion of the pack being multi-year ice, as the enclosed nature of the Arctic means that things “swill about” a lot more. Much of that multi-year ice is now gone, and with it the “memory” of cooler times. This means that the Arctic is more vulnerable to local weather conditions than it has been for… well, at least my lifetime. The _volume_ of ice will hence be significantly less than previous years, even if a thin ice cover approaches average. Thats if it can get to average missing so much ice that normally “carries over” from the previous season.

    As Luke says, treat the Antarctic quite separately. As it is not enclosed, and hence the ice can be far more divergent, small shifts in weather systems can result in significant shifts in the ice edge through Ekman drift. (ie ice is formed nearer the coast and gets “pushed” northwards – it doesnt stay where it forms for very long).

    I suspect the dry April in Australia and the northward shift in ice are linked, and likewise the April trend in both; down in Aus rain and up in April SH ice, possibly both related to a more negative SAM index.

  7. Comment from: Bob Tisdale

    Here’s a curious graph: Inverted Annual Arctic Sea Ice Anomaly vs NH SST. You’ll see why I inverted the sea ice data.

    Note that, based on the upswing in the smoothed lines, the Arctic Sea Ice starts its decline in 1969, eight years before the start of the rise in NH SST. Hmmm??!!

  8. Comment from: Denialist Scum

    “We need a pretty pickie, with lots of clean white ice.”

    And a polar bear. It won’t be taken seriously unless there is a polar bear in the picture as well. Preferably a happy polar bear – one that is revelling in all this CO2-induced sea ice.

  9. Comment from: cohenite

    Being visually cued I find Cryosphere fine, despite their dental disclaimer on the main page; if this ice isn’t increasing I can’t see the polar bears for the eskimos;

  10. Comment from: Anthony

    Sea ice extent doesn’t mean much. How thick is it?

  11. Comment from: Linda

    Hello, I posted this over on Watts website but this seems the perfect place to post it as well. I was wondering why there has been no response on any of the blogs or websites about the following news story that was just released about scientist predicting another major artic ice melt this year.
    here is the link to the story

  12. Comment from: Denialist Scum

    “I was wondering why there has been no response”.

    What can you say? The poor fool is a day late and a dollar short. More to be pitied than despised.

  13. Comment from: Ian Mott

    If even the boy wonder is now suggesting that we treat Antarctica differently to the Arctic, can we conclude that he now agrees that there is no such thing as ‘Global’ warming?

    Surely, those nations that border the North Atlantic have an issue with ‘regionalised warming’ that will produce both adverse and beneficial impacts as climatic variation always has done.

  14. Comment from: Alarmist Creep (Lucy - the artist formerly known as Luke)

    Nope not suggesting that at all. It’s important to not confound data sets. And yep Europe does enjoy the benefits of warming circulations.

    But looking at many different data sources there is quite good evidence that “much” of the world has seen a warming trend.

    Antarctica and the SH should be different. More ocean in SH And Antarctic circulation, particularly of recent years, tends to wall the continent off.

    And the same argument you’re using needs to done for rainfall in Australia – overall rainfall no trend – but regionally we have significant deficits in some areas – east, south-east, south-west and areas that have become wetter (north-west).

    The warming itself is not the real issue – it’s what happens to the extremes !

  15. Comment from: Max

    Doesn’t it occur to anyone that the reason sea ice is shooting up is because the glaciers that have been held back until now are slipping into the sea?

    Unless I hear otherwise from a reliable source, this is cause for alarm in my eyes.

  16. Comment from: Ron Jung

    Why are the graphs starting with 1979? Why not 1936 or so when conditions were similar to today?

    Paul – Because that’s when the satellite records begin.