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’ll run this poll each month in the week before the deadline, and we’ll see how we do as the minimum approaches. The value used by ARCUS 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.
Here’s the latest JAXA graph:
JAXA AMSR-E Sea Ice Extent -15% or greater – click to enlarge
On May 30th I submitted the results of the first poll to ARCUS to be included in their June Outlook, as shown below:
Download High Resolution Version of Figure 1.
WUWT is second highest, at 5.5 million sq km. Notably missing this year is “Wilson”, who in the last two years started out with impossibly low values such as 1 million sq km. I’ll repeat the poll next week in preparation for the July Outlook. In the meantime, check the WUWT Sea Ice Page for the latest.
Here’s the poll for the ARCUS July outlook, it will run until July 30th at noon EST.
Tim Channon says:
June 27, 2011 at 8:02 pm
Tim, this link has most of what you could ask for. It’s loaded with plots, but the real substance comes in the links to downloaded data. 🙂 It’s not much effort to get it into a spreadsheet and start analyzing trends yourself.
http://wattsupwiththat.com/reference-pages/sea-ice-page/
-Scott
“Hudsons Bay is not landlocked”
I meant in terms of growing ice extent. Wrong choice of wording on my part.
well sharks you have two approachs. Pam says above 5.5 and refuses to disclose her method. except to say “its mechanics” and “science”. Me? I say 4.5. Method? easy. its 2008, assuming the mechanics are the same as then ( big assumption) it’ll be closer to 4.5 than it is to ABOVE 5.5.
Funny how you like secret methods with no methods and no maths to check
By the way, with La Nina barely hanging on but for ENSO neutral and La Nina returning forcasts, the chance is greater for a negative AO, meaning weaker polar winds. So I stand by my +5.5 prediction. We are not set up for a strong wind pushing ice around and down through Fram strait. The day to day ice movement grid also shows very weak ice movement up there. If the polar vortex picks up, then I will be wrong by a long shot.
Lowesssssssst everrrrrrrrrr! (A mere signpost on the way to the end of the interglacial)
I get confused about the AO and polar vortex. If it is a negative AO and low polar vortex in Winter then this leads to less ice, however if it is a negative AO and low polar vortex in summer then less storms result at higher lattitudes so more melt in situe ( even if the winds are less).
Hence, by my reasoning ( which I admit may be screwy) a negative AO will not hinder ice loss
TimC says:
June 27, 2011 at 11:58 am
“I thought Dave Springer’s thermostat concept must be essentially correct – but this must be largely a NP phenomenon, for while the arctic basin could be completely ice-free at onset of winter, in the Antarctic that would be impossible anywhere over 75 degrees S, due to the land-based ice sheet.”
Largely, yes. There’s some variability in SH sea ice but the sweet spot where ocean heat content can escape is blocked by a continent. Arrangement of the continents has a lot to do with climate. The current arrangement is evidently favorable for an ice age.
John F. Hultquist says:
June 27, 2011 at 10:03 am
Dave Springer @ur momisugly 7:17
says “We know global average temperature has been rising. We got 30 years of satellite data to prove that.”
“We do? Check the graph in the link below.”
Yes, we do. The trend is upward. It’s mostly below the zero line in the first half of the record and mostly above it in the second half. If you can’t eyeball that you might want to get your eyes examined.
RobbCab says:
June 27, 2011 at 9:12 am
“Nice attempt at a drive by. The ENTIRE article is about temperatures at equal pressures.”
Venus is a red herring. No sunlight penetrates to the surface. It’s hot enough to melt lead on the surface because, unlike the earth, once the internal heat of the planet reaches the top of the crust it can’t radiate out into space but must continue to make its way slowly through an atmosphere 80 times denser than the earth’s. Internal heat has virtually no effect on surface temperature on our planet. Only a few milliwatts per square meter comes from below because the crustal rocks are very good insulators and it can readily escape once it reaches the end of the rocks while at the same time a couple hundred watts per square meter reaches the top of the rocks from the sun. On Venus no heat from the sun reaches the crust as it is all blocked by the atmosphere while the internal heat of the planet can’t escape easily until it reaches clear sky. So the internal heat of the planet builds up quite high in the lower atmosphere.
None of this stuff should be called the greenhouse effect. It’s much more apt to call it the insulation effect. Venus has a great deal of insulation its atmosphere which masses 80 times greater than the earth’s. It insulates the surface from solar heating in the upper atmosphere and insulates the surface against internal heat loss to space.
A very ignorant assertion is made about Venus in that the surface temperature is a result of Boyle’s Law i.e. gasses undergoing compression heat up and those undergoing expansion cool down. The ignorant part is conflating compression with pressure. The surface pressure of the Venusion atmosphere is static. The only way it could experience any compressional heating is if the pressure were constantly increasing i.e. undergoing compression. Once the compression stops and pressure becomes static Boyle’s Law no longer applies.
So it looks like my spreadsheet doesn’t mean too much on June 30. Correlations are very poor, especially in the last decade. Consequently, I’m taking the same approach as Steve Mosher, but I’m using 2010 as my proxy instead of 2008. I’ll assume equal loss wrt to 2010 in the coming months.
The average for June 1-29 for 2011 is 53000 km^2 higher than 2010. From that, I’m guessing we’ll end that much higher, so my guess is 4.95 million km^2, smack dab in the middle of 4.9-5.0 million. Note that this should make Mosher happy, because it’s slightly different than my guess of 4.8-4.9 million last month. 😉 I put in my vote about 12:04 EST, so hopefully it counts. On the bright side, it looks like the 5.0-5.1 vote is going to win this month, which is much more reasonable than last month (a lot fewer total votes this month, so maybe fewer passers-by than last time?)
We should learn a lot in July. Correlation approaches that are nearly worthless now are quite telling by July 31. This will be an interesting year I believe. Last year fell in the this odd middle ground where everyone tried to claim victory. If PIOMAS is right, we almost have to see a smaller extent this year than last year (especially considering that CAGWers claimed that last year’s weather was ideal for keeping ice). If PIPS is right, we almost have to see a larger extent this year than last year (especially considering that CAGWers claimed that last year’s weather was bad for keeping ice).
-Scott
Good thinking there Scott and nice analysis.
Daily rate of ice loss is at the higher end of the spectrum currently so sub 5 million is still well on the cards.
Andy
AndyW says:
July 3, 2011 at 10:04 am
The analysis is very simple, but probably as reasonable as any other unless one gets heavily involved with estimated thicknesses, SSTs, projected weather patterns, etc.
Sub 5 is definitely on the cards and probably more likely than > 5. I would argue that sub 4 might even still be in the cards (it would take a 2007-type loss…well, slightly worse than that).
-Scott
Hi Scott,
Just had a quick look at previous years on which day of the year extent went below 8×10^6km2 in conjunction with final extent :-
2002 27 July => 5.6 final
2003 28 July => 6.0
2004 31 July => 5.8
2005 20 July => 5.3
2006 18 July => 5.8 ( very slow August)
2007 13 July => 4.3
2008 21 July => 4.7
2009 20 July => 5.2
2010 17 July => 4.8
2011 is currently on track to hit sub 8 from 12th to 16th July so even if it is a very slow August like 2006 then it puts an upper limit of about 5.5 on things for final extent. More likely to be be closer to 2007. Currently I am thinking 4.5 to 4.6. My original estimate from very early in the year was about 4.75.
Andy
By the way, with La Nina barely hanging on but for ENSO neutral and La Nina returning forcasts, the chance is greater for a negative AO, meaning weaker polar winds. So I stand by my +5.5 prediction. We are not set up for a strong wind pushing ice around and down through Fram strait. The day to day ice movement grid also shows very weak ice movement up there. If the polar vortex picks up, then I will be wrong by a long shot.
#################
nice to make a high low bet.
What’s the chances that the polar vortex picks up? and how far off will that make you.
2011: 12.79, 11.01, X (1.78)
2010: 13.1, 10.87 , 4.6 (2.23)
2009: 13.39, 11.48 , 5.1 ( 1.91)
2008: 13.18, 11.44, 4.52 (1.74)
July 2010 was not very good for daily extent loss, not that many days over 100 000, I think 2 or 3 from memory, this year we have already had
-149375
-168125
-75782
-102968
-81719
-117969
-149844
2007 had about 10 or 11 ( again from memory)
At this rate the time to reach sub 8 million square kilometres in extent will be the earliest in the short JAXA history
Looks like 2011 broke through 8 million in extent on the 10th, beating 2007 by 3 days.