Poll now closed. Results below will be submitted to ARCUS on Sept 1st.
Once again, I’m going to give WUWT readers an opportunity to make a forecast for submission, based on voting. See the poll at the end. I’m late getting this online this month as other things took precedence.
For reference, here’s last months forecast poll and the final submission with all other forecasts from other groups. The final forecast poll you can participate in follows.
The value used by ARCUS in the forecast is the NSIDC value as they say here:
The sea ice monthly extent for September 2010 was 4.9 million square kilometers, based on National Snow and Ice Data Center (NSIDC) estimates.
So don’t be using the JAXA graph to forecast minimums, though it it useful for determining short term trends as it is more responsive than the NSDIC graph below, which is averaged.
Right now the NSIDC value is about 5 million square kilometers.
[ UPDATE: NSIDC’s Julienne Strove from NSIDC writes in comments:
“Note, the NSIDC value today is 4.66 million sq-km.”
Of course NSDIC doesn’t publish the daily values like JAXA does, so we all have to guess since we aren’t privy to that information.
The 5 day average graph is all the public gets. And of course, any estimate is hampered not only by the average, but also by those coarseness of the Y axis. I’ve asked before for NSIDC to publish the daily value and the response has been that they have more important issues to attend to. However, clearly the ARCUS forecast group is watching this number and it is important to the final forecast done by over a dozen groups now. So you think it would be valuable to post the daily data. -Anthony]
Here’s the latest JAXA graph:
JAXA AMSR-E Sea Ice Extent -15% or greater – click to enlarge
Here’s the poll for the ARCUS August outlook, it will run until Sept 1st at midnight PST.
(NOTE/UPDATE: This poll was originally exactly like all the others done over the last several months, but one snarky commenter (the first one) complained that I was a “manipulator” because it didn’t have more lower values. Of course he never bother to ask why or look at the history of the other polls.
I had considered initially adding those lower values for this poll, but then figured I’d be derided for changing the poll and not being consistent with the other polls. In retrospect, I’ll be criticized no matter what I do, so within 20 minutes of it going online, I decided to extend this poll with 0.1 million km increments down to 4.0 million kilometers. I’ve also removed the options for voting 5.5 to 6.0 (which existed in prior polls) since they are outside the current bounds of possibility based on previous September history. – Anthony
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TheTempestSpark says:
August 31, 2011 at 8:49 am
My guesstimate and vote is 5.4 to 5.5 Million km2, I’m not educated to make guesstimates nor is the sea ice extent my area of expertise, but just for a bit of fun I’ll go with 5.4 to 5.5 Million km2 for four reasons.
1. It looks like La Niña Will Return This Winter.
2. Many parts of Europe have experienced it’s coldest summer in 20 to 50 years respectively.
3. Low solar activity.
Solar activity is higher now than it was at the time of the record sea-ice minimum in 2007.
@Martin Clauss
Concentration gets better because melt ponds freeze over as well as small cracks…OBS show thickness over most of the ice pack is low. Cocentration would be 100 percent if the entire arctic was covered in 10Cm of ice with no cracks.
“The southern route of the Northwest Passage now appears to be free of sea ice according to imagery from the University of Bremen and the NSIDC Multisensor Analyzed Sea Ice Extent (MASIE) analyses. However, U.S. National Ice Center analyses indicate that there may be up to 20% ice concentration remaining in some parts of the route.”
This from the NSIDC web site.
1 Is it gibberish?
2 Is the North West Passage navigable at present?
3 Why don’t they go and see?
Anthony
Keep up the good work and remember the nit pickers are just nits?
Back at the beginning of the melt season I predicted the min at 4.285714 Mkm2, fully expecting to be on the low side, but since my estimates of 5,714285 Mkm2 for the last several years had been on the high side I was hoping to bring my avg prediction closer to the avg observed number. In case you’re wondering, my habit of making predictions out to 6 decimal places is meant to be a subtle jab at the tendency of most of these clucks to log their data out to the nearest km2 when their supporting documentation usually indicates that they’re probably only good for the nearest 0.2-0.5 Mkm2. The need for a semi-random looking but easily memorable 7 digit number has lead to my highly scientific methodology for smoothly extracting my predicted value from my anal orifice. Looking at the numbers should give the more arithmetically astute among you a strong clue as to what that method is.
You may have also guessed that I don’t take any of this crap very seriously. In that you would be correct. Having inquired on numerous occasions as to what exactly is the catastrophe that is supposed to occur if and when the sea ice in the Arctic should go to zero at the minimum, the only answer that has ever been suggested is enhanced ocean warming from the sunlight falling on the expanded areas of open water. My response, since at least ’08, has been to suggest that low solar angles, and the albedo of ocean surfaces at such angles, and rapidly dwindling daylight in the month of September when such a zero point would likely occur, suggest that phenomenon, should it occur, is unlikely to be significant. Indeed we have been experiencing expanding areas of open water in the Arctic for more than two decades now and if anyone can provide a link to some negative climate phenomenon that is well correlated to that expansion I would certainly appreciate it, because my own efforts to find one have so far been entirely unsuccessful.
A few weeks ago I suspected my low ball estimate might actually turn out to still be too high, but just in recent days both the CT and Nansen graphs of sea ice area are suggesting an early bottom, though it’s way too early to say at this point. BTW, does anyone else find it curious that CT’s number for SIA has been close to a million km2 smaller than any of the others that track that metric for at least two seasons now? WUWT?
@ur momisugly Stacey
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2011242.terra.4km
the NW passage has opened up on both routes?
I am not sure what you are getting at.
Can I start by echoing Mr Watts’ frustration with the non-availability of daily (or 5 day averaged) SIE data from the NSIDC. As mentioned, Jaxa do this as a matter of course, as do CT. The historic month-end averages are of course available from the NSIDC at…
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/
Having to try and extract numbers from a chart is rather like placing a horse behind the cart. (Reversal of an old proverb – justified on grounds of poetic licence.)
However, and this just could be my 122 year old eyes (between them) playing tricks, when I extend a horizontal onto the y-axis of the above NSIDC chart (for 30th August) it looks a lot closer to around 4.7 – 4.8 million sq km than it does to 5 million. Julienne indicated that today’s (31st Aug) figure was 4.66, so that would seem to stack up.
I know a couple of people have tried to answer Merrick’s question about the September (yep, that’s the key word) average and how some people can by still sticking with a number that has already been passed for the daily figure. Lacking access to the NSIDC historic daily data, is a bit of a pig, but one can at least get a feel for things by using the Jaxa CSV file. If one looks at this, there have indeed been 2 occasions on which the September average ended up being higher than the daily figure for the last day of August – namely 2002 and 2004.
Mr Watts also wisely warns against over reliance on Jaxa daily figures to help predict the equivalent NSIDC monthly average. The Jaxa versus NSIDC September averages over the 9 years since they both became available are a bit lopsided. From 2002 until last year, the figures in millions of sq km (with the Jaxa numbers shown first) are as follows…
(2002) 5.89/5.96; (2003) 6.13/6.15; (2004) 5.96/6.05; (2005) 5.53/5.57; (2006) 5.91/5.92
(2007) 4.38/4.30; (2008) 4.84/4.68; (2009) 5.38/5.36; (2010) 5.10/4.90
The reason for splitting these comparisons into two batches is that the ratio crossed unity. For each of the years between 2002 until 2006 the NSIDC figure for the mean September SIE exceeded the Jaxa figure by an average of about 46,000 sq km. However, for each of the last 4 years, the Jaxa figure has been higher, and has averaged around 110,000 above its NSIDC equivalent.
How will they compare this year – I’ve no idea.
@ur momisugly Dave Wendt
CT Uses a 6.25km grid resolution.
Jaxa uses 12.5km grid resolution.
Norsex uses 25km grid resolution.
Hi Rod, errors in the daily data (either from us or from JAXA) will result from (1) weather effects, (2) land-contamination, (3) missing swaths (or delay in getting all the swaths), (4) geolocation issues (the near-real-time data we get has not gone through the rigorous geolocation/calibration as our “final” data set does). We are well aware of these errors, which is one of the reasons why a 5-day running mean is used on our ASINA page. But another important thing to note is that after we receive the better quality-controlled brightness temperatures from RSS, all the data is once again reprocessed. So when you go to the Sea Ice Index (ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/) for the monthly data you will notice that there are final #s (the Goddard ones), preliminary #s and the near-real-time #s, and these will eventually be updated.
Thus I don’t agree with your statement: In fact, doing so increases the odds that errors will be more quickly uncovered in either data collection or calculation, because others are checking the figures daily.
The data providers (NSIDC, JAXA, Bremen, etc.) are well aware of the potential errors in the daily #s. We worry that others won’t be.
But I agree that it would be a good idea for NSIDC to make the daily #s available though (with all the caveats clearly stated).
Julienne Stroeve says:
August 31, 2011 at 6:58 am
Note, the NSIDC value today is 4.66 million sq-km.
———————–
The daily value reported on the Masie page hosted by the NSIDC is 4.87 million km^2.
http://nsidc.org/data/masie/index.html
Corresponding image from today which says 4.9 million km^2.
ftp://sidads.colorado.edu/DATASETS/NOAA/G02186/png/masie_all_zoom_v01_2011242_4km.png
Bill, some of the historical daily extent data is here: ftp://sidads.colorado.edu/DATASETS/seaice/polar-stereo/trends-climatologies/ice-extent/
there you have access to both the “final” NASA Team and Bootstrap #s.
Thanks for the JAXA/NSIDC comparison, that is interesting and I’m not sure why the differences between the two data sets change after 2006. The 2008-2010 #s from NSIDC will still change though after the NASA GSFC folks send us an updated data set.
Phil. says:
August 31, 2011 at 10:53 am
“Solar activity is higher now than it was at the time of the record sea-ice minimum in 2007.”
Hi Phil, that’s true!
One years solar minimum is irrelevant but not insignificant in Solar Cycle Progression and as 06,07,08,09 and 2010 were years with lower solar activity before 2011 (which is still lower compared to 00, 01, 02 and 2003) thats why I said “Low solar activity” and not ‘No solar activity’,
I would expect there to be lower activity before minimum ice extent rises/grows if there is a time lag between the warming and cooling of the planet due to solar activity.
And like I said, I’m not an expert on arctic sea ice extent but I understand the fact that these cycles are observed over large timescales between cause and effect, and the next solar maximum intensity is predicted to be much lower than 00, 01, 02 and possibly 2003, It therefore seems logical to me that there will be more Arctic ice build up over the coming decade, that’s why I chose the high guesstimate and vote of 5.4 to 5.5 Million km2, there is still a whole month of declining Arctic temperatures that could tip the scales in favor of my vote (whats a million or so km2 in planetary scales), but I think it’s very unlikely that the Arctic will be Ice free this year or decade maybe not even this century, unlike some of the “Experts” in the field that have been franticly Exclaiming that it will.
(Did I mention that I’m NOT an Expert in Arctic Sea Ice?) 🙂
Chris Biscan (@ur momisuglyFrivolousz21) says:
August 31, 2011 at 11:22 am
@ur momisugly Dave Wendt
CT Uses a 6.25km grid resolution.
Jaxa uses 12.5km grid resolution.
Norsex uses 25km grid resolution.
Thanks for that. Interesting that a 12.5 km gr change between JAXA and NORSEX yields not much difference, but an extra 6.25 km gr change yields such a dramatic difference.
Not entirely off topic:
Reality of Sea Ice is Starting to Bite
http://autonomousmind.wordpress.com/2011/08/31/reality-of-sea-ice-is-starting-to-bite/
South Pole Explorers worried about climate change and the melting Antarctic are losing their ice breaker because the Swedish Government needs it to maintain shipping lanes during the upcoming winter in the Baltic.
The article includes a letter to Hillary Clinton among other interesting information like the big question why the NSF failed to maintain the US Icebreaker fleet.
I learned something today.
I had always thought, as a non scientist, that these ice prediction threads were a bit of fun. A humerous diversion from the front line, like soldiers playing laser squad.
The vitriol in some of the comments has made me think again. It’s nasty out there!
why did science ever come to this ? It’s a crying shame
EO
re: Chris Biscan (@Frivolousz21) says: August 31, 2011 at 2:46 am
That paragraph isn’t cut off in any way by the image in my browser, so you may want to consider either a different screen resolution or a different browser, if the image is causing yours to have problems.
it isnt “science” the politics are NASTY and have nothing to do with science which is impersonal and impartial.
If I had to put my current line of thought on the role of these factors by percentage for different time periods here goes:
(DIRECT FACTORS, NOT INDIRECT)
natural Variability
GHG’s(including Co2)
Temperatures, including SST’s
1979-2011:
Natural variability(40%)
GHG’s(20%)
Temperatures(40%)
2007-2011:
Natural variability(10%)
GHG’s(10%)
Temperatures(80%)
Since 2007 the role of AGW has likely went from 30-40% of the ice decline from 1990-2006. And Temperature feedback has gone up exponentially.
If this process can be shutdown by something else for a while…I can definitely see the ice stopping and gaining volume for a while. Until AGW catches up wit the ever increasing rise of GHG’s.
On the flip side if this does not get impeded. We are about to see the ice dramatically drop to possibly near ice free conditions in less then 5 years.
The data on this is clear. The SSTs are crushing the ice from the sides and from below. Not AGW currently, even though natural variability and AGW were triggers for the SSTs to get out of control and decimate the ice.
it is likely since the early to mid 2000s that Ice volume was crippled.
If this continues, we will see the bottom drop out so to speak.
As in the ice as we can see in the laptev will melt out from below, not from the top or sides.
This is a complete admission that i estimated AGW’s role in this as a much larger factor then it was and has been.
However SSTs are much more dangerous and deadly for ice in the short term.
Forecast interval categories of 1/4 standard deviation are pure roulette–if you happen to “win” with such a play, it is pure luck, not any skill whatsoever.
I’ll stand by my prediction your May poll: 4.5 or less, for the same reason I did then.
http://wattsupwiththat.com/2011/05/19/sea-ice-news-call-for-arctic-sea-ice-forecasts-plus-forecast-poll/#comment-665723
Back then, ~85% of Wattsers polled felt it would be higher than it is now. ~20% of Wattsers overpredicted by more than ten times the spread. I wonder what this set of dart throws will show.
How the #s stack up for August 30th (actual daily values, not the 5-day running mean).
In my opinion, given the uncertainty in these #s, 2007 and 2011 are tied at the moment.
2007 2008 2009 2010 2011
4.5886 5.07877 5.33669 5.21215 4.65878
Looks like we’re going to settle in somewhere between 2007 & 2008, so around 4.4 million sq. km. More important though is of course sea ice volume, and in this category, even by conservative estimates, we’ll have far and away the least amount of arctic sea ice by total volume. Sorry skeptics, but no sea ice recovery in sight, and in fact, quite the opposite. Expect 2007’s record low extent to be beaten by 2015 at the absolute latest– New Little Ice age is postponed indefinitely.
re: Günther Kirschbaum says: August 31, 2011 at 2:50 am
Gunther, your backhanded ‘damned if you do, damned if you don’t’ attack on Anthony is both unwarranted and wrong. Anthony did make a prediction this year, and linked to it in a comment above yours.
Making out like someone is a fool if a prediction isn’t correct is just absurd. A bunch of top experts have been playing the same game year after year, and the majority of them wind up with incorrect, often wildly incorrect, predictions. Either you must therefore claim that they are all fools (which frankly I think makes you look pretty foolish, not them) or one must recognize that it is a complicated system with many variables that make it almost impossible to ‘correctly’ predict what the final ice amount will be. What fun would a prediction contest be if it were easy to know what the final result would be?
To make out like anyone, expert or non-expert, somehow owes an apology or mea culpa when they get the final ice extent number wrong is, well, assinine. Anthony displays no hubris or arrogance in making his predictions – he just puts it out there dryly, often along with an explanation of his reasoning. The only possible way it would be reasonable to then castigate any of the folks participating in the contest or even just making a prediction, no matter how far off they were, would be if they claimed they were right when they weren’t. I sure haven’t seen that, and I don’t believe you or Chris have either.
Please, check your bias at the door, would you?
“Bremen Prelim map is out and shows another massive loss day coming. After tomorrow this will slow down a lot and we can go from there. This one is going to be huge though, maybe record setting if it was September But August is going out with a bang. Likely 100-150K on all three major reporting places.”
more flash melting???.
Whats the weather like? That could be impacting the measures. If you have large storms like you did that day ( aug21-22) when the “flash melting” occurred, you had better be wary of the data and wait a day….
“No warranty, expressed or implied, is made regarding the accuracy or utility of the data! False ice concentrations can occur due to bad weather systems”
and if they are all using microwave sensors then I would be wary of chest thumping until a few days have passed. personally, I’d wait for 5 day averages, and then celebrate the demise of the ice.
Bill Masie numbers are computed with an entirely different set of source data and they use a different method. you can compare it with itself and thats about it.
bill the frog says:
August 31, 2011 at 11:19 am (Edit)
Can I start by echoing Mr Watts’ frustration with the non-availability of daily (or 5 day averaged) SIE data from the NSIDC. As mentioned, Jaxa do this as a matter of course, as do CT. The historic month-end averages are of course available from the NSIDC at…
#######
data sets are created for different uses, for example some are created for operational use and they need to be done daily. You can see this if you READ the dataset documentation which details the PURPOSE of the particular dataset. There are plenty of unreliable daily datasets to busy yourself with. I would not add another to the stack.
@Rational Debate
I was under the impression that Mr. Watts predicted a min extent of 5,750,000km2
With all of the data out there, that would have been absurd. That is all. I wanted accountability for such an absurd prediction. I apologized immediately for my attitude towards that.
I deal in facts. I have no problems apologizing or admitting I am wrong.
I just do not like when people make bogus bias opinions…this goes on both “sides is.”
We have more real time data then ever now.
@StephenMosher
there is a relatively weak SLP that has formed the last 3 day and slide from the Bearing to the Western/Central Arctic. This has caused a 15-20mb gradient between it and the HP sliding south over the Beaufort. This spawned 10-18kt winds over a wide area.
Because the ice is weak and the SST source of the winds are record warm Bottom melt/compaction has caused this. This lasts one more day before winds go chaotic in the Arctic.
Today will be a major drop and tomorrow will be big then we can reevaluate things with a better forecast.
I have learned to use daily 3 day forecasts for my ice ideas. It has proven to be extremely effective in nailing daily ice loss.
by day 2-3 things get chaotic. I have to admit to under estimating the loss of ice with the ice being so thin and waters so warm.
Even with colder temps a chaotic SLP based September pattern with that warm water out there and thin ice could upheaval warm water that is killing the ice from underneath. Stay tuned.