Note: I second Steve’s thanks below to Dr. Meier for his essays (part1 and part 2) that enable us to have this discussion.
Back on Feb 9th, 2010 WUWT readers polled that Arctic sea ice would be recovering over 2009, by a wide margin of 69.8%. We’ll see how that pans out this year. We did pretty well last year.
As leader of the WUWT “Ice Team”, I’ll ask that when the time comes, that we all scream for the Ice Team that comes closest to predicting the actual the Arctic Sea Ice minimum, then buy the other team a beer.
The next few weeks will be entertaining, perhaps even stressful, as we watch each twist and turn in agonizing slow motion. But, let’s all take it in stride, no matter who “augers in”, may the best team win. 😉
– Anthony
By Steve Goddard
First, thanks to Dr. Walt Meier at NSIDC for taking the time to write up his very informative recent article on WUWT. It is much appreciated. In that article, Dr. Meier made this statement :
As NSIDC states in its most recent post, we’ve expected we may see the rapid decline begin to slow because the melt will soon run into older, thicker ice, which will slow the loss of ice. Steve has said essentially the same thing and indeed we’ve the rate of loss slow over the past few days.
The NSIDC newsletter which Dr. Meier refers to is dated July 6, 2010.
However, it would not be surprising to see the rate of ice loss slow in coming weeks as the melt process starts to encounter thicker, second and third year ice in the central Arctic Ocean. Loss of ice has already slowed in the Beaufort and Chukchi Seas due to the tongue of thicker, older ice in the region noted in our April update.
Note that the slowdown actually started a few days before NSIDC published their forecast for it. NSIDC only produces one newsletter per month, so this may just be a matter of timing.
By contrast, my forecast came three days ahead of the slowdown and was very precise.
stevengoddard says:
June 28, 2010 at 10:16 pm
In three days, the slope of the Arctic extent graph will begin to drop off.
Mark it on your calendar.
NSIDC also noted in their July 6 newsletter the possible similarity between 2006 and 2010.
Weather conditions, atmospheric patterns, and cloud cover over the next month will play a major role in determining whether the 2010 sea ice decline tracks at a level similar to 2007, or more like 2006. Although ice extent was greater in June 2007 than June 2006, in July 2007 the ice loss rate accelerated. That fast decline led up to the record low ice extent of September 2007.
By contrast, I clearly noted the similarity to 2006 over six weeks ago – at a time when the extent graphs showed 2010 far below 2006. My observation was made based on PIPS thickness data, which allowed me to make a very early prediction.
Can we find another year with similar ice distribution as 2010? I can see Russian ice in my Windows. Note in the graph below that 2010 is very similar to 2006.
Bookmark this post for reference in September.
June 1, 2006
June 1, 2010
Six weeks later, 2010 extent is very close to 2006 – just as the PIPS data indicated it should be. It is important to note that whether or not PIPS thicknesses have correct absolute values, I am only using it for comparisons relative to other years. The absolute thicknesses are not important – as long as their methodology is consistent from year to year.
‘
Conclusion : The PIPS thickness data has been an extremely good indicator of 2010 Arctic ice conditions. Thanks to reliance on PIPS data, WUWT has been far ahead of the curve in forecasting future 2010 ice conditions.
Coincidence? Not very likely. Theory is fine, but it is difficult to argue with results.
Can we do analyses like these for Antarctic ice or do we not have the thickness data?
Even if we do have thickness data, I suppose it is a significantly different animal, it being an island surrounded by open ocean.
Can we expect mea culpa from Romm, for this exceptionally clueless piece from May 24?
http://climateprogress.org/2010/05/24/arctic-sea-ice-extent-volume-nsidc-record-steve-goddard/
Any volunteers to remind him in his comments section? I can’t do it, because I would get censored or selectively edited.
Warren says:
July 14, 2010 at 8:20 pm
It gets silly after those paragraphs.
“If the decline in the sea ice continues – as predictions of global warming suggest it will – it is feared that the bears could die out in 25 to 30 years, or perhaps in as few as 10, if there are a succession of years with very low sea ice cover”
Actually, I think I agree with them Warren. According to wikipedia, the font of all human knowledge, the life expectancy of a polar bear is about 26 years. So I can almost guarantee that the bears living in Hudson Bay right now will mostly all be dead in 25 to 30 years time.
/sarc off
As I posted previously, the more negative AO winters tend to have a slower melt in the summer all else being equal. Of course, not all summers are equal, but the trend definitely holds fairly strong.
The last 3 decently -AO winters have been 2009-2010, 2005-2006, and 2000-2001, of which the previous 2 have had high mins (2000-2001 a very high min). The middle case, 2006, we obviously know a lot about because its on the jaxa record. It flattened out very fast with the extra multi-year ice held in along with a non-hostile pattern for ice loss in summer. The summer pattern still matters a lot, but the Beaufort Gyre being enhanced in the -AO winters tends to really help out in the prevention of major ice loss after those winters. 1995-1996 is another good example. 1996 had a very weak melt.
In contrast, if you look at the lower extents in history (compared to years around them), they generally followed major +AO winters. 1988-1989, 1994-1995, and 2006-2007 are good examples. This isn’t an airtight argument because there are still other factors and as a result a few exceptions to the rule, but its good evidence that the winter AO might play a significant role.
We still have a ways to go to see where 2009-2010 finishes. Its been flattening a lot recently, but it doesn’t mean it still cannot be an outlier and finish pretty low.
Smells like Teen Ice.
=============
I completely agree with Dave Wendt’s comments about this site.
Cheers to Anthony for a monumental task [the search for truth] made palatable…in the form of WUWT. I love this place!
Meanwhile, thanks also to Steve Goddard for his incessant assault on the sea ice misinformation police.
Looks like ice thickness and girth….matters.
Good ole’ PIPS. If its good enough for the mightiest Navy in the known universe, it should be more than good enough for R Gates.
Chris
Norfolk, VA, USA
Anthony got it right in one image: Aerial manoeuvre, the Full Serreze.
I think that the minimum Arctic sea ice extent will be slightly larger than in 2009.
Now, I still don’t have a “Dr.” before my name (could have collected doctorates by the dozen but was too fastidious). Which means that if I am right, I am “lucky,” and if I am wrong… but I am never wrong, that’s the problem.
Coincidence? Paul the Octopus predicted all world championchip matches correctly he had been “asked” about. So if something that is not made to predict certain things still produces good results does not mean it actually works. For how long are you using PIPS to make your predictions? If it worked for you for a decade – well, it probably just works. If you only do it for 2-3 years you cannot know whether it works (just saying, since you begged the question yourself).
Matthias
The odds of correctly predicting ten consecutive football matches are 1024/1
“stevengoddard says:
July 14, 2010 at 11:46 pm
Matthias
The odds of correctly predicting ten consecutive football matches are 1024/1”
That is only true if both teams are equally good, and if there is no tie.
The odds of correctly predicting ten consecutive football matches are 1024/1
Yes, but an octopus has 8 arms. 😉
The sharp decline in June was due to areas outside of the Arctic Basin (like the Hudson Bay) melting out. It became clear at the end of June that Hudson Bay would be clear of ice on July 1, and that there was almost no thin ice left to melt anywhere. As a result, ice loss came to nearly a hard stop on July 1.
Steven, thanks for the answer. There is one thing I don’t understand. Why didn’t the 2007 ice loss have a hard stop at a certain point? Is that because 2007 had a lot more thin ice?
At some point later in July, it will probably start to pick up again.
Why will it start to pick up again if there is no thin ice left to melt anywhere?
PS I’ve only just noticed it, but in the article’s title it says NSDIC (should be NSIDC).
“Can we expect mea culpa from Romm, for this exceptionally clueless piece from May 24?”
I think comments are closed, at least I can’t seem to respond. Smart of him to do that. Some of the comments are priceless in there. They are just so cute and smug, I wonder what their excuse will be when there’s 2M km^2 more ice this September….
Steven,
the question was for how many years PIPS has been used for prediction, not what the odds are to guess 10 consecutive football matches.
FYI
For those who aren’t pilots: there’s no aerial maneuver called The Full Serreze. The picture is an aircraft in a spin. Been there, done that, a few times. Easy to do. Full throttle, yoke all the way back, mash one rudder pedal to the floor. The trick is coming out of it alive. In a forgiving aircraft like the Cessna 172 I flew all you have to do, aside from beginning the maneuver a few thousand feet AGL, is cut the throttle, let go of the yoke, and apply a little rudder in the direction opposite the spin.
Curious about the name I googled Full Serreze and found a Dr. Mark Serreze of the U.S. National Snow and Ice Data Center who has a history of making dire warnings about arctic ice loss.
Good one, Anthony.
Matthias
PIPS has been used by the Navy for decades as their operational ice model.
Günther
Winds have been spiraling away from the pole, lowering the ice concentration. That means more water is being heated by sunlight, and eventually this will show up as ice loss in the graphs.
If you look at JAXA by eyeball, you see a point ~Aug 5 where 2006, 2008, and 2009 are practically right on top of each other. I suspect 2010 will likely closely join that grouping on that date.
So what drives what happens after that date, from Aug 5 to the end of September and minimum? To me, it seems likely that the available amount of multi-year ice is the major answer (tho certainly wind and tide play a role).
2007 “headed for the basement” quite early, starting around July 5 or so. So far, 2010 shows no such inclination. The rapidity of the May/June melt for 2010, in my mind, is an artifact of the late surge to maximum in late March of this year. The youngest ice is the thinnest ice, and in retrospect it makes sense that such a late surge in extent would melt off correspondingly fast.
Returning to 2006/2008/2009. . . .look at the “sag” (i.e. post Aug 5) difference between 2008 and 2009. Why is it there? It’s there because 2009 had much more second year ice than 2008 did (after the 2007 outlier). 2010 has more 3rd year ice, and much more second year ice at this point than 2009 did and far more than 2008.
Am I suggesting that wherever 2010 is on Aug 5 that I expect the “sag” difference to be of the same amplitude between 2010 and 2009 as it was between 2009 and 2008? Well, that would be nice, but I suspect not –there has got to be some kind of asymptotic ice-age maturity function going on here.
So, anyway, back in late April I began telling WUWT that I would find anything that wasn’t truly eye-poppingly unusual between May 1 and July 1 unintersting, and that my next major checkpoint was July 1-July 15, just completed. In my view, that policy has been confirmed by events.
And now my next major checkpoint is Aug 5. See you there.
David says:
July 14, 2010 at 8:35 pm
I think I saw him commenting on some other threads within the past few days, but he doesn’t appear to be commenting on sea ice currently.
Most of the AGW crowd here has either departed from the Sea Ice discussion or are switching tactics back to the “long term trend is still down” approach. See, for instance:
Thrasher says:
July 14, 2010 at 7:38 pm
&
Regg says:
July 14, 2010 at 4:56 pm
They don’t seem to realize that, though the long term trend is still down, the point is to show that the claim(s) of no summer sea ice by
20082013 don’t look to be coming true.-Scott
Steve
this is what I am trying to get at:
Mr Meier said in his first article:
“2. Validation of PIPS (see references above) has been done for sea ice extent, concentration, and motion near the ice edge (an important factor in the day-to-day changes in the ice edge). This is because the ice edge is the area of operational interest – i.e., the focus is on providing guidance for ships to avoid getting trapped in the ice. Very little validation was done for ice thickness estimates, particularly in the middle of the ice pack.”
The way I understood it is that PIPS isn’t really made to forecast thickness, espcially with view to PIPS’ purpose of making practical predictions for only a few days into the future.
Now, to connect this to my question: You seem to rely on their thickness data nonetheless, stating how well it apparently worked, but also asking whether this be merely a coincidence. I was wondering whether you might believe it could be merely coincidence after all in light of PIPS not being meant for thickness prediction (or rather: did I get this correctly?).
So when I ask for how many years you have used PIPS thickness data to predict a slowdown in melt, the question could be rephrased to ask whether even though PIPS may not have been made with thickness prediction in mind, does it still reliably work for melt slowdown predictions of yours nonetheless? And if it worked for you not only once or twice, but rather reliably, then this would suggest that your predictions are not merely coincidential.
Maybe I am missing the obvious and the question is silly altogerher, but certainly your second answer also did not address my question. The question was not for how long PIPS is in use, it was for how long YOU used PIPS thickness prediction for your own predictions in slowdown of melt. Or at least that was what I was trying to ask in the first place. Was my queston simply “weird” / off the mark in this context or is it you not wanting to state for how many years you did your predictions based on that PIPS data? Or both? 🙂
Prediction: 5,301,000 sqkm
Matt
I have been using PIPS for six weeks, and so far everything has been close to perfect.
I calculated that in order to stop the long term downwards trend, the summer minimum would have to be 22 million km^2.
Isn’t it NSIDC?
REPLY: Yep fumble fingers on my part, fixed -A
Steve–
I’m going to go out on a limb here and say 22M km/2 is not in the cards this year.
However, bending the decline of the LT “less downwards” would only take about 5.5M km/2, right?