ARCUS: July Sea Ice Outlook Published

WUWT comes in at the median value of 4.6 million square kilometers (they rounded up from our 4.55 submission) . It is important to note that even with the large losses in June, nobody who submitted to ARCUS is forecasting the “ice free arctic” to match Jay Zwally’s outlandish claim of “…the Arctic Ocean could be nearly ice-free at the end of summer by 2012″

See the graph below to take it all in. 

From ARCUS: July Sea Ice Outlook.

Figure 1. Distribution of individual Pan-Arctic Outlook values

Figure 1. Distribution of individual Pan-Arctic Outlook values (July Report) for September 2012 sea ice extent.

Download High Resolution Version of Figure 1.

With 21 responses for the Pan-Arctic Outlook (plus 5 regional Outlook contributions), the July Sea Ice Outlook projects a September 2012 arctic sea extent median value of 4.6 million square kilometers (Figure 1). The consensus is for continued low values of September sea ice extent. Individual responses are based on a range of methods: statistical, numerical models, comparison with previous rates of sea ice loss, composites of several approaches, estimates based on various non-sea ice datasets and trends, and subjective information. Again, it is important to note for context that the estimates are well below the 1979–2007 September mean of 6.7 million square kilometers. The quartiles for July are 4.2 and 4.7 million square kilometers, a rather narrow range given that the uncertainty of individual estimates are on the order of 0.5 million square kilometers. This is also a narrower range than last year, which was 4.0 to 5.5. The July Outlook is generally similar to the June Outlook; the July median is higher by 0.2 million square kilometers than the June estimate, but the quartiles are similar.

Just after the June Outlook was completed (based on May data), arctic sea ice extent briefly set record daily rates of loss.

Figure 2. Daily sea ice extent as of 7 July 2012.

In June we saw the second-most cumulative loss in the satellite record since 1979, behind the record minimum extent for June in 2010. We also saw cases of early melt in some regions. The culprit for the rapid sea ice loss in early June was again the presence of the Arctic Dipole (AD) pressure pattern, but the pattern shifted towards the end of the month and ice loss slowed.

Figure 4. Sea ice extent for 5 July 2012.

The Sea Ice Outlook is organized by the Study of Environmental Arctic Change (SEARCH) and the Arctic Research Consortium of the U.S. (ARCUS), with volunteer efforts of Outlook contributors. Funding is provided by the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA).

As always, for a complete view of Arctic and Antarctic sea ice data, visit the WUWT Sea Ice Reference Page.

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29 thoughts on “ARCUS: July Sea Ice Outlook Published

  1. It is interesting to observe it – and important to know that the ability TO observe ice in these far-off locations is so new that it is probably really irresponsible to draw any conclusions from short-term observations.

  2. Awww….WUWT is running with NSIDC (Julie et al)… Who would have thunk it? I am going with the NRL and the fancy models ;)

  3. I will admit to being biased, but Canadian Ice Services made an accurate prediciton last year; the first year they participated in this study. This year they have forecast 4.7 in both June and July. I would note that of all the participants in the study, I believe CIS is the only participant where their guess really matters. The Canadian Coast Guard has the job of using it’s icebreakers to escort various supply ships to bring heavy loads to remote communities in the Canadian north. The planning for these convoys is based on data provided by CIS, and this needs to be good, otherwise vital supplies may not reach these northern communities.

    So my advice is watch CIS. My bet is that they will be correct again this year.

  4. Doesn’t that depend on your definition of what ‘nearly’ means?

    Lol, I love when these proponents of AGW use – weasel words

  5. It stands to reason then that the loss of extremely thick multi-year ice in the mid to late 90’s has allowed the rather common atmospheric pressure dipole to more readily move less thick ice out of the arctic. That means that some brilliant AGW scientist needs to show that CO2 upticks in the mid to late 90’s caused the loss of hard to move ice back then which has set up the current conditions.

  6. Don’t you get tired of this natural temperature cycling to be blamed on
    ‘anthropogenically enhanced global radiative forcing’?
    How about a milder ice loss than the 30’s being called ‘unprecedented’?
    How about ignoring Asian soot’s effect on ice, blinded by CO2 obsession?

  7. 4.6 x 10^6 km^2 of ice. How much is that compared to the land area of the continental US?

    For a thought experiment to help visualize this amount of ice, I consider the US to be utterly flat – that is devoid of topology and an imaginary perfect circle of ice of this magnitude placed pretty close to the center of the continental US. I chose approximately half way on the north/south border of Nebraska and Kansas.

    Next derive R = Radius; knowing Pi * R^2 = Area = 6.4 * 10^6 ; R = approx 1200 km. Draw circle.
    States partially enclosed (from a fraction to over 7/8) establish a border; and note circle extends into Canada about 200 km:

    Texas, New Mexico, Arizona, Utah, Idaho, Montana, (hits Canadian border), Michigan, Ohio, Kentucky, Tennessee, Alabama, Mississippi, Louisiana. Portions of these states and all states bordering on those states are completely covered in ice.

    This exercise is done as a rough gauge of area – maybe my map is off in it’s projection; maybe my math is a bit (but I checked it with a square – looks right!); anyhow – that’s a lot of ice. I mean, drive from Utah to Ohio – all ice. Lots of ice.

  8. There’s a couple of things you don’t seem to understand so I’ll explain them to you.

    Firstly, July is not the end of summer.

    And secondly, “could be nearly” does not have the same meaning as “will be completely”.

    You’re welcome, any time.

  9. Two questions for Kwasi:

    Who is claiming that July is the end of summer? This article is about predictions, made in July, of end of summer ice.

    What value is “could be nearly”? 4.6MM might be “could be nearly”, if the initial value was 4.6billion, but the initial value is less than 16MM. So is 4.6MM “could be nearly” of 16MM or is “could be nearly’s” value significantly less than 4.6MM? At what value could Zwally say, “See, I was right.”

  10. Oh oh. I hope I didn’t get WUWT into trouble with my Zwally vote. WUWT’s submission ranges all the way down to <1.

    Hey, Kwasi, is <1 almost could be nearly maybe or something? And btw, next time be more careful about making assumptions about what people "don't seem to understand." The misunderstanding might, again, be yours.

  11. It’s very interesting that Anthony keeps snipping the start of Zwally’s quote… [AT THIS RATE]“…the Arctic Ocean could be nearly ice-free at the end of summer by 2012″. On the face of it, he is not making a prediction, just stating a fact based on the (short term) rate at that time.

    BUT… Instead of focussing on red herrings such as this short term and off-the-cuff ‘prediction’, lets look at the long term trend showing accelerating loss in the arctic. Of course rates of loss can change or even reverse, unfortunately we can’t remember the future.

    (source accelerating loss http://www.springerlink.com/content/c4m01048200k08w3/)

    REPLY: Oh, please.

  12. Mat L says:
    July 12, 2012 at 9:57 pm

    It’s very interesting that Anthony keeps snipping the start of Zwally’s quote… [AT THIS RATE]“…the Arctic Ocean could be nearly ice-free at the end of summer by 2012″. On the face of it, he is not making a prediction, just stating a fact based on the (short term) rate at that time.

    The same thing can be irresponsibly said during every summer melt – “At this rate the ice will be gone by….”

    The same thing can be irresponsibly said about a stock that loses $1 a day for three days. “At this rate the stock will be zero by…”

    Zwally knew exactly what he was saying. He cherry picked a time interval to measure a “RATE” that would support the radical claim that he wanted to make in order to get the news coverage that he wanted.

    He didn’t disclose the fact that his RATE was measured stupidly and that such an extrapolation was idiotic. Stop pretending that he said, “In the unlikely event that this very short-term rate continues….” And stop pretending that he cautioned people NOT to print the headline, “SCIENTIST WARNS THAT ARCTIC COULD BE ICE FREE BY SUMMER 2012.”

    And stop pretending that he asked for any corrections. What’s funny is that the CAGW proponents, after being silent about the wording for years, are NOW suddenly concerned about getting it right.

    He conveyed exactly what he wanted to convey, and now he must live with that.

    Thank you for giving me the chance to address this.

  13. Anthony, any idea why the ARCUS guys rounded ‘up’ the WUWT 4.55 entry ?
    With 4.55 WUWT would have been smack in the middle of the pack.

    Either way, with 4.6, WUWT is exactly in between the 2011 ‘winners’ (both correct in predicting 4.6 correctly in 2011) :

    Lukovich et al now predicting 4.3
    Blanchard-Wrigglesworth now predicting 4.9

    It’s good to see that WUWT readers have come to their senses, and are voting realistic numbers now.
    In fact, linear extrapolation between last year’s 5.1 and this year’s 4.55 suggests that WUWT predicts an ice free Arctic by 2020.
    Which is earlier than most ‘alarmist’ would dare to put forward :o)

  14. Rob;
    linear extrapolators cause multitudes of ‘orrible accidents every time they reach a corner. Beware!

  15. I am fed up to my back teeth with people who say “At this rate by “whenever” it will all be gone!” I have heard this expression all my life & have never actually witnesses such a state of affairs, apart from the sales of beer in the local shop at half price for a bank holiday weekend when we had a summer, whenever that was! :-))

  16. Mat L, by your logic, we could say, based on the current (short term) rate, the Arctic will be ice free by early November. Would you make excuses for that type of comment, as well?

  17. ‘Mat L says:
    July 12, 2012 at 9:57 pm
    It’s very interesting that Anthony keeps snipping the start of Zwally’s quote… [AT THIS RATE]“…the Arctic Ocean could be nearly ice-free at the end of summer by 2012″. On the face of it, he is not making a prediction, just stating a fact based on the (short term) rate at that time.’

    One thing for sure some of us would like too know?

    Is there any correlation between upto 30 icebreakers in the Arctic during the spring/summer season and increased ice loss. Particularly to carving channels in the ice and the increase of ice loss vulnerability to current and wind patterns caused by all that ploughing through the sea Ice?

    I’ve seen quite a few photos of claimed MSM Arctic GW melting sea-ice loss over the years. Turned out just to be tracks carved into the ice by ice breakers!

    Greenpeace should be the first to boycott their own use of ice hardened ships and their own icebreaker in the Arctic if they want to save the polar bears. :-)

  18. Marian, your question was answered a while back on the NSIDC Icelights blog: Are icebreakers changing the climate?

    How much ice does an icebreaker break?
    Meier decided to crunch some numbers and find out. While his numbers are an estimate, he said, they provide a helpful comparison of just how much icebreakers might contribute to summer ice loss.

    Meier said, “In late June, when the sun’s energy is strongest, the total sea ice extent is around 10 million square kilometers or 3.9 million square miles. An icebreaker cruising through the ice for 1,000 kilometers (620 miles) and leaving an ice-free wake of 10 meters (33 feet) would open an area of water 10 square kilometers (3.9 square miles) over the entire cruise.

    In contrast, the Arctic sea ice cover decreases by an average of over 9 million square kilometers or 3.5 million square miles each year during its melt season—an area larger than the contiguous United States. In total, researchers estimate that the number of icebreakers traversing the Arctic at any given time is usually less than three. So, Meier said, “The actual contribution is miniscule—only one part in a million of the total ice cover.”

    I hope you find this convincing.

  19. Arctic sea ice is declining both in area and volume.
    It is likely that it is the result of human induced climate change caused mainly by carbon dioxide emissions from fossil fuel use.
    The arctic is warming faster than the rest of the planet.
    The NSIDC plot a straight line though their measurements of average monthly sea ice extent (recorded from the start of the satellite data in 1979 to the present).
    However, the September plot (when the ice area minimum usually occurs) is not a good fit for a straight line decline.
    If the decline did though continue as a straight line, the arctic will be largely ice free at the end of the melt season in about 2065.
    If the decline rate of the last decade continues as a straight line, the arctic will be largely ice free by about 2030.
    If the decline continues to accelerate, as it has done since the late 1990s, then the arctic will be largely ice free in September in about 2019.
    Take your pick.
    All 3 scenarios will have major impacts on climate in the northern hemisphere. On the evidence (as opposed to blogosphere ramblings), its just a question of when it happens.

  20. Günther says:
    July 14, 2012 at 1:45 am

    Marian, your question was answered a while back

    That answer doesn’t address this part of Marian’s question:

    and the increase of ice loss vulnerability to current and wind patterns caused by all that ploughing through the sea Ice?

    It seems as if Marian is asking about the blocks of ice which are carved free to float south and melt. Ice which wouldn’t otherwise melt.

    Honestly, I don’t think it’s significant, but the answer you provided doesn’t address it. So, why would she find such an answer convincing? Did you realize this?

  21. That answer doesn’t address this part of Marian’s question:
    and the increase of ice loss vulnerability to current and wind patterns caused by all that ploughing through the sea Ice?
    It seems as if Marian is asking about the blocks of ice which are carved free to float south and melt. Ice which wouldn’t otherwise melt.

    Check out the arctic satellite pictures. Maybe zoom in to the closest resolution possible, and look at all the natural cracks and holes, much much larger than a ships path.

    http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic

  22. You still haven’t addressed the question. Just because the natural cracks and holes are larger than the ship paths doesn’t mean that the ship paths aren’t materially contributing to an “increase of ice loss” due to “current and wind patterns caused by all that ploughing through the sea Ice”.

    Again, I doubt it’s material, but you haven’t demonstrated that it’s not.

  23. A few weeks ago I stated the Arctic ice melt would not go north of the New Siberian Islands because “it’s too cold up there”. I meant the Franz Josef islands, east of Svalbard. Sorry. (unimportant I know)

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