Over the past few days, Arctic sea ice extent has braked dramatically in the daily loss rate and now has made a sharp right turn, which is rather unusual. Here’s the JAXA extent:
And here is a close up view, note the 2011 red line:
That turn is unique to the record since 2002. Note that in 2007, there was also a turn, though brief, and then melt accelerated.
It is also showing up in the NSIDC plot:
But what is really most interesting is the plot from DMI, which show not only a turn, but a reversal:
What does this mean? The short answer is, probably nothing. When we approach the minimum, and the ice pack becomes more fractured and scattered, it also becomes more susceptible to the vagaries of local and regional wind and weather.
WUWT regular and contributor “Just the facts” suggested in comments that:
One factor appears to be the Greenland Sea, where sea ice began to grow on July 15th and has been trending above average since then.
Source: ftp://sidads.colorado.edu/DATASETS/NOAA/G02186/plots/r07_Greenland_Sea_ts.png
On the other hand, looking at the most recent comparison with 2007, the Arctic ice cover looks a bit more soupy in 2011:
Air temperature is above freezing throughout the Arctic….
…as is fairly normal for this time of year:
Clearly, at present, air temperature in the Arctic is not in any way climatologically abnormal, so the reasons for the current extent being low and making erratic turns must lie elsewhere. Wind, soot deposition/albedo, ocean currents, etc. all factor in.
So, while we may have temporarily avoided a new record minimum (as many in the “Serreze death spiral” camp said we are headed to) there’s still the possibility that the plots will turn to the left again, and resume or even accelerate. It all depends on the weather, and the outcome could go either way at this point. Historically, we have about 7 more weeks before the turn upwards as the Arctic begins the slow re-freeze.
Still, it makes for interesting observation and discussion. The WUWT sea ice page has all the latest stats, updated as soon as they are made available.
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UPDATE: Bill Illis runs his own database, and offers this interesting view in comments.
The last 21 days are the lowest melt since 1973 in my database over the same period. The total ice extent is still well-below average but there are very few periods in the record where the trend is so different than normal for an extended period of time like the current period is.
Matching up a few different datasets back to 1972.
UPDATE2: In the meantime, while extent loss slows, the NSIDC “death spiral team” tries to make a case for a record low average for July, while at the same time admitting that On July 31, 2011 Arctic sea ice extent was 6.79 million square kilometers (2.62 million square miles). This was slightly higher than the previous record low for the same day of the year, set in 2007.
Arctic sea ice at record low for July
Arctic sea ice extent averaged for July 2011 reached the lowest level for the month in the 1979 to 2011 satellite record, even though the pace of ice loss slowed substantially during the last two weeks of July. Shipping routes in the Arctic have less ice than usual for this time of year, and new data indicate that more of the Arctic’s store of its oldest ice disappeared.
Figure 1. Arctic sea ice extent for July 2011 was 7.92 million square kilometers (3.06 million square miles). The magenta line shows the 1979 to 2000 median extent for that month. The black cross indicates the geographic North Pole. Sea Ice Index data. About the data.
—Credit: National Snow and Ice Data CenterHigh-resolution image
Overview of conditions
Average ice extent for July 2011 was 7.92 million square kilometers (3.06 million square miles). This is 210,000 square kilometers (81,000 square miles) below the previous record low for the month, set in July 2007, and 2.18 million square kilometers (842,000 square miles) below the average for 1979 to 2000.
On July 31, 2011 Arctic sea ice extent was 6.79 million square kilometers (2.62 million square miles). This was slightly higher than the previous record low for the same day of the year, set in 2007. Sea ice coverage remained below normal everywhere except the East Greenland Sea.
more here
I don’t know if this is a statistical fluke or what, but I’ve discovered an “August 28th leading indicator” for IARC-JAXA data. The rule is that however the August 28th IARC-JAXA values are ranked by year, so too will the minima be ranked. E.g. 2003 has the #1 (i.e. highest) August 28th value, and the highest overall min. 2004 has second highest August 28th and overall values. For what it’s worth, here are the numbers. I’m looking forward to 1400Z August 29th for the IARC-JAXA August 28th value, to see where this year slots in.
Year Overall Overall
Year Min Value Rank Value Rank
2003 6032031 1 6353125 1
2004 5784688 2 5971563 2
2006 5781719 3 5966406 3
2002 5646875 4 5957656 4
2005 5315156 5 5771250 5
2009 5249844 6 5554219 6
2010 4952813 7 5342656 7
2008 4707813 8 5163125 8
2007 4254531 9 4724844 9
Jigs and jogs aren’t all that unusual. The lines tend to cluster together most of the time, and geographic constraints result in significant autocorrelation. Anything could happen. Well, anything but Serreze retracting his death-spiral cant.
Kadaka,
To perpetuate this bit of fun…
If you had historic castles in the US you would know that the castle turrets were designed to have a clockwise orientation so as to afford the right-handed swordsman defender a greater advantage over the right-handed swordsman attacker who would be baulked by the wall. Ergo, in true warmist logic, we in the UK have it right! Of course, left-handed swordsmen would have been fine, but unfortunately they were all burned as witches for being weird.
Usual PC caveats apply… no offence meant to either warmists or lefties, etc…:)
Arfur
Mods said:
[snip – policy violation – trying to advertise a website on art prints]
Sorry – that was definitely not the intent. Lesson learned.
@Caleb
I remember you predicting this some weeks ago: an above average melt followed by an unexpected early flattening out.
Something changed in the Cryosphere today image data this year, it shows larger day to day variability in colour pattern. I would take it with a pinch of salt.
SandyInDerby says:
August 3, 2011 at 2:47 pm
Correct – illustrating what happens when one posts in haste and has a poor memory! My bad! When I checked the archive sometime later I realised my mistake! I guess I was remembering that there were several years with significant summer temp variation and my brain was essentially ‘noting’ that this year the graph seems to have closely follow the mean line…
I suppose, if air temps are fairly ‘normal’ then any melt acceleration must be related to ocean heat/currents, etc.
Hmm, is that tick left turning or anti clockwise?
Only joking.
Last few days on JAXA are
-23281
-22969
-34687
-18594
-2500
-25938
so not very big at all, certainly not compared to the start of July when it was 100 00+. Maybe it will pick up again though. The AO seems to be turning once again more negative and the pattern of High and Lows up there may revert to looking like start of July again. Certainly the warm southerly winds from the Russian side have not been blowing of late and assisting the insitue melt and compaction, if they start again it should pick up as it looks pretty crumbly on that side.
Andy
Ed Mertin says:
August 3, 2011 at 7:09 pm
As I recall Pamela called this last week. Well done, Pam!
Actually she said the opposite, if the AO gets more positive then ice extent loss will increase, when actually it has decreased. That is because she is of the opinion it is mainly wind driven.
Andy
commieBob says:
August 3, 2011 at 12:26 pm
anticlimactic: The energy to melt the ice comes from the sea, not the atmosphere
Then how do melt ponds occur and why does the snow around Barrow dissappear in summer?
Andy
If its responding to the somewhat lazy sun already, it could even bottom out above 6Mkm3.
I doubt it very much, but if you continue the curvature, that’s where it ends up !!
Anyone want to start guessing values for December ??
How would AGW bletheren feel if it was above 12Mkm3 in December 😉 That would be fun to see !!
Has any of this ‘early melting’ to do with the recent nearby volcanic activity on Iceland? And I think I recall there has been recent underwater volcanic activity around the Arctic itself. Has anyone done any comparisons to see if there is any relationship between the two?
SandyInDerby says:
August 3, 2011 at 2:47 pm
Kev-in-Uk says:
August 3, 2011 at 11:48 am
Kev,
the DMI has graphical data on the Artic temperature back to 1959 here.
http://ocean.dmi.dk/arctic/meant80n.uk.php
The summer temperature seems to be pretty stable over the years where as the rest of the year the temperature can vary quite a lot. It is as if there is a ceiling that the temperature can not rise above?
Anthony I know you blokes over in America drive on the wrong side of the road, I have driven in America on a motor cycle and did have a few problems.
This arctic ice gives me a clue as to my driving problems, if you were on the red line traveling from west to east and did a right turn you would be headed south. This graph is heading north.
This explains my driving problems, your right turns are my left turns, riding a harley in California with these differences, I count my blessings.
My take on this arctic ice turn is that the ocean under the ice has lost its heat. I have said before that the melting of the ice is the start of a cooling. Melting Ice takes a lot of heat and open water in the far north dumps a heap of heat to space.
For better eyeballing the JAXA Data: This picture shows the Extent-Anomaly in comparisation to the previous years: http://www.dh7fb.de/noaice/max11akt.gif
and this one http://www.dh7fb.de/noaice/icelossakt.gif shows the daily extentloss also in comparisation to the previous years and the average of 2003…2010.
Both pictures are updated almost every single day.
Frank
RE: phlogiston says:
August 4, 2011 at 12:33 am
“Something changed in the Cryosphere today image data this year, it shows larger day to day variability in colour pattern. I would take it with a pinch of salt.”
I’ve sensed the same thing. I find it irksome, for I tend to think in pictures. If I can’t get a clear picture, my thinking is fuzzy.
I have great respect for the great brains who post on this site, and marvel over their math, and am humbled, for, compared to them, I’m a math moron. However, to pump my ego back up, I use the following analogy:
Suppose you are coaching a baseball team, and you have two outfielders, one who has an IQ of 160 and a second who has an IQ of 60. When you hit a fly ball to the genius he whips out a calculator, does calculations with amazing speed, and comes up the answer just as the ball bounces off his head. When you hit a fly ball to the moron he watches it go up, runs to where it will come down, waits, and catches it.
In terms of math, I’m the moron, but if I get a clear picture of things I sometimes can figure out where the ball is going to land. Therefore I wish I could be more certain I was getting a clear picture from Cryosphere today.
Caleb
I agree with your baseball analogy. Climate is complex with many factors combining in unknown ways. Being too mathematical with climate can lead you up the garden path – CAGW is an example. In biology with even more complex systems, mathematics plays only a peripheral role.
@R Gates
Quick to call “divergence” when extent increases (relatively speaking) but when extent falls we don’t hear much from you about “convergence” (wind packing the ice closer) – then its all about the catastropically warming Arctic. Anyway we’ll see if your prediction of an early responsive fall in extent happens or not…
RACookPE1978 says:
quote
(Should the late war have gone the other way, would the Argentines been forced to convert their tanks?
unquote
The Argies demonstrated their consideration for the inhabitants of their new colony by immediately enforcing a drive on the right policy. They left a nice lot of Merc jeeps, all LHD, for us to drive after they’d legged it. And, oddly, they sh*t on everything, even going so far as to trowel the stuff into a house fusebox. But I digress.
kadaka (KD Knoebel) wrote
quote
Also, as revealed by new research (for those who didn’t realize it from mere common sense), distracted driving is a major cause of accidents. So the best thing is to do quickly whatever control fiddling is needed so you can sooner return your attention to the road and get both hands back on the wheel. This is best accomplished with your most dexterous hand, which is normally a person’s right hand. So right side of the road driving remains more correct.
unquote
You have created in this post a model which, if we are to trust you, must be testable to see if your hypothesis is correct. You have made a common error by not showing your data.
Your model shows that countries with the steering wheel on the left will have a lower accident rate than those with RHD. What does the data say?
BTW, not all cars have power steering — my Midget is completely free of all mod cons. Mind you, it was built in 1967.
(See, Anthony, even distractions can give valuable insights into GW science! And if you’d like another description of what that line is doing, it’s turning widdershins.)
JF
Maybe I should have been a teacher….
I’m sticking with my under 4.5 guess. If 2007 was wind-driven, then a repeat of strong winds in August should flush a lot of ice from the Arctic because it looks a lot less concentrated than it was in 2007, plus the NE passage is open already and never did open in 2007. It just seems like it’s set up to be easily flushed this year if the winds are right.
Note that the area graphs keep falling at a decent clip, indicating that melting is going on at a more or less normal pace, but I don’t think the winter build up was as good as previous years so there’s less to melt this year. With melting still continuing and the ice spread out like it is, it seems to me like it would just melt faster in place and be even more prone to a faster flushing when (or if) the winds finally pick back up.
phlogiston says “In biology with even more complex systems, mathematics plays only a peripheral role.”
That is factually incorrect. In fact one of the major initiatives by pretty much all of the major firms is to spend more time modeling and doing analytics across their R&D portfolio.
Been watching this every day. If you look at the arctic air temperature anomaly, it is sharply negative, which is what is driving the trend. I would bet that we are near the bottom for 2010 ice.
If this is true, the Western USA is in for one HELL of a winter. Temps in the bay area are barely breaking 70
Okay, Andy, I’ve been known to be wrong when my thinkolator is fried. It doesn’t take long to bake a gourd in Ft. Smith, AR at 115°F (new record) & McAlester & Atoka, OK at 113°F which is where I was at the time. Baking it some more in Schulenburg, TX… at least the trees are green. In Oklahoma everything is various shades of brown.
Dennis Wingo says:
August 4, 2011 at 9:55 am
Been watching this every day. If you look at the arctic air temperature anomaly, it is sharply negative, which is what is driving the trend. I would bet that we are near the bottom for 2010 ice.
_____
Ice melt is now being driven more by water temps than air temps, and water temps in and around the Arctic remain quite high. We are far from the bottom. I expect a dramatic downturn soon. 2011 will certainly be lower than 2010, and its far too early tell about winter weather, but the association between sea ice extent and harsh winters in lower latitudes is more inverse…with warmer Arctic weather and less sea ice more closely associated with harsher weather further south.
Wow, just took a look at the satellite images, lots of holes opening.
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2011216.terra.4km
phlogiston says:
August 4, 2011 at 4:46 am
@R Gates
Quick to call “divergence” when extent increases (relatively speaking) but when extent falls we don’t hear much from you about “convergence” (wind packing the ice closer) – then its all about the catastropically warming Arctic. Anyway we’ll see if your prediction of an early responsive fall in extent happens or not…
_____
I call it like I see it. When ice is compacting, I’ll say it is. Early in the melt season, April-May-June, the ice is still to concentrated to really diverge or compact too much. It is really later in the melt season July-Aug-Sept that we can start to get big divergence and compacting of the ice as the concentration is lower and weather systems can diverge or compact all that “soupy” ice more easily. Overall, the long-term trend of year-to-year Arctic sea ice extent, area, and volume is clear to all but the most hardened of skeptics…and it’s down.