Sea Ice News #21

Phil Nizialek,
“Secondly, I still would like to know what our AGW believer colleagues propose to do about the trend (if it is primarily anthropogenic). When you answer, beware the law of unintended consequences, my friends.”
I suggest you read Al Gore’s “Our Choice” and James Hansen’s “Storms of my Grandchildren” and perhaps a few other books or, if you prefer, blogs if you really want to know what people who consider AGW a serious problem think ought to be done. If you’re too lazy to do some reading of easily available written materials in order to satisfy your desire, I fail to see how any of us here creating yet more detailed written material here in response to your question is going to help you.

In reverse chronological order, here are my weekly (p = 0.5 or 50% or even money chance of occurence) Monday estimates (JAXA 2003-2010 inclusive) for Arctic sea ice extent (date, extent (km^2), standard deviation (km^2));
9/6/2010,4.869E06,0.054E6
8/30/2010,4.916E6,0.091E6
8/23/2010,4.898E6,0.152E6
8/16/2010,4.835E6.0.215E6
8/9/2010,4.812E6,0.267E6
8/2/2010,4.681E6,0.332E6
7/26/2010,4.587E6.0.360E6
7/19/2010,4.493E6,0.418E6
7/12/2010,4.271E5,0.476E6
7/5/2010,3.973E6,0.534E6
6/21/2010,3.886E6,0.646E6
6/28/2010,4.048E6,0.711E6
6/14/2010,4.057E6,0.716E6 (Time zero ~ midpoint of melt season or ~ three months before expected minimum)
Quite consistent over the past month or so, but no guarantee of the final minimum, by any means.
Date of minima is the same for all estimates 9/19/2010.
The following sequence is for p = 0.5 or 50% or even money chance of occurence.
-28,233 (9/7)
-26,948
-26,079
-25,332
-23,629
-21,179
-18,584
-15,953
-13,632
-10,977
-8,045
-4,650
-1,436 (9/19)
Final extent = 4,868,605 km^2
Updating (NSIDC for the 6th) the ensemble slope of Bremen (8/26-9/7), JAXA (8/25-9/6), and NSIDC (8/25-9/6), the ensemble slope is -0.33K/Day (R^2 = 0.89).
For each individual dataset;
Bremen slope is -23K/Day (R^2 = 0.92)
JAXA slope is -30K/Day (R^2 = 0.92)
NSIDC slope is -45K/Day (R^2 = 0.99).
The following sequence is of very low probability (< 1% at this time) but is consistent with the current ensemble slope;
-31,884 (9/7)
-31,461
-31,122
-30,027
-28,942
-28,368
-28,217
-28,352
-27,997
-26,611
-24,011
-21,372
-18,188
-14,019
-9,086
-4,574
-1,237 (9/23)
Final extent = 4,707,812 km^2

R. Gates,
You believe that within the lifetimes of most people posting here, we will see an ice-free arctic! Good! You made the right choice when you used the word “believe”. AGW religion requires faith and belief. Keep the faith man! Keep the faith!

rbateman says:
September 7, 2010 at 9:53 am
Hi Robert. Here in the UK we have the same arguments bandied about every decade or so and numerous stats are produced one way or t’other. In the end I doubt it makes much difference, except perhaps for road traffic accidents around the switchover as you say. What struck me about this report is that the words ‘climate change’ and ‘global warming’ don’t appear once, which is at least encouraging even if it is a rag doll 🙂

Gary Pearse says:
September 6, 2010 at 2:43 pm
My points were a Feb 2010 prediction of 57skm is not so bad given how far off some were in August 2010
Yes, I think Anthony Watts will be proven more accurate than Charles Wilson, when this summer melt season ends.
Well played.
hey in this business these predictions were better than those who are paid to make such predictions.
Those SEARCH predictions are just a friendly competition between scientists (and sometimes undergrads and grad students) – it is not considered their “day job”. It’s like pro baseball managers giving their opinion on who will win the World Series – they are definitely knowledgeable about the teams, but they are not “paid” to predict the Winner.
Re your descending ice extent at steeper than linear trends, tomorrow or the next day the line will bend up again – this is September. A lot of the trouble with the thinking on both sides of the debate (but more on the AGW side) is this simplistic notion of linear trends in a cyclic world.
Did you look at the plot ?
http://tamino.files.wordpress.com/2010/07/pred2010.jpg
The data points are for September minimum sea ice extent – for 31, and soon to be 32, years. The decline is not linear, it is accelerating. The final September value might be slightly higher than that red dot in the plot – causing a slight refit of the quadratic, but the decline is still accelerating compared to the 80’s, 90’s and 00’s.
Watch the curve level off and curve up again as it even did in 2007 around this time.
You’re thinking of a different curve:
http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Extent_L.png

Phil Nizialek says:
September 7, 2010 at 6:18 am
It seems to me that all us sceptics are just going to have to sit back and eat some crow for a year (at least) on the Arctic Sea ice extent. There’s no denying at this point that 2010 will fisinsih below 2009, and given current trends (always subject to change) probably below 2008. The gloaters are pouring forth their sarcasm, and so it goes in these debates.
I still have a couple of questions though. First is why a 30 year trend of ice loss on one half of the globe is considered gospel, and never subject to reversal. If there’s one thing all of us should recognize, climate seems to rarely if ever continue trends indefinitely. Many non anthropogenic factors could act to reverse this trend, and soon. We have to follow the trend for a lot longer than 30 years, which seems to me at least an impossibly tiny amount of time in the context of something as hopelessly complex as earth’s climate.
Secondly, I still would like to know what our AGW believer colleagues propose to do about the trend (if it is primarily anthropogenic). When you answer, beware the law of unintended consequences, my friends.
___________
First, though I am a “warmist” in the sense that I believe it is more likely than not that AGW is happening, I have no intention of making any AGW skeptic eat any crow…unless of course, they want to launch ad hominem attacks my way, then I may change my mind.
My interest is, and always has been, one of looking for the truth. This is the main reason that I maintain a 75/25 warmist/skeptic split in my mind when it comes to AGW. Yes, I beleive it is likely happening, and if I had to place a bet, I would put my money on the line that it is happen, and furthermore, that we can see it most readily in the changes we are seeing in the Arctic. However, I am always on the look out for other alternative possibilities and influences, and certainly don’t completely discount the notion that a longer term cycle in the PDO, AMO, solar cycle, etc. could also be at work in adding to or even completely causing much of what is taken as AGW…but my belief right now is that these other influences are less likely than AGW.
What to do about the loss of Arctic Sea ice? (if indeed it is from AGW). I’ve not gone there yet. Depsite the ad hominems on me, lumping me into the “catastrophic” category of AGW believers, I’m not there yet, I’ve never taken the next step and said what the consequences will be from an ice free summer Arctic, or what we ought to do about it. Some species may benefit and some will likely not be so fortunate. One thing I a definitely opposed to at this point is any sort of geoengineering to try to “fix” the issue. Just from a purely scientific perspective, if humans are causing the climate to change, then geoengineering efforts will likely only make the matter worse, as we would be introducing one more factor into the mix in a system on the edge of chaos that would already be out of balance. If humans are causing AGW and climate change, then probably the best solution is to create societies in which we all consume much less and consumption is not the basis of our economies. Of course, we can all practice this on our own, as I do, and I know others here (including Anthony) already do as well to one degree or another.

All the talk of whose predictions were (or will be) more correct than others is interesting, but, just consider.
What if the high arctic had been at average temps, instead of colder than usual?
What if it had been a sunny year in the arctic, instead of unusually cloudy?
What if the winds were favorable for ice export, instead of not?
And still, look where it’s ending up.

Djon says:
I suggest you read Al Gore’s “Our Choice” and James Hansen’s “Storms of my Grandchildren” and perhaps a few other books or, if you prefer, blogs if you really want to know what people who consider AGW a serious problem think ought to be done. If you’re too lazy to do some reading of easily available written materials in order to satisfy your desire, I fail to see how any of us here creating yet more detailed written material here in response to your question is going to help you.”
Sorry to offend, Mr. Djon, but I think you missed my point. I’ve read a bit here and there about what Mr Gore, Mr. Hansen and others propose to do about AGW. I guess I could be a bit lazy, not having read it all, and maybe I needed to be more clear that I find most such ‘solutions” to be, at least to me, far worse and unpredictable than the perceived problem. My hope was to generate a conversation on possible solutions, since many here seem to think any further discussion of the nature of the problem is futile.
Mr. R Gates, I certainly never meant to question your motives in presenting your evidence, nor your credentials as a lukewarmist. The bone I have several times tried to pick with you is your reliance for your views on a 30 year trend. I think the trend is too short, for reasons I’ve mentioned in earlier posts, to justify the crisis type predictions many here posit. You believe otherwise, which is fine, except that your statement that “my belief right now is that these other influences are less likely [a cause of the melt] than AGW” is not really a reason that causes me to seriously reevaluate mine.

That is a horrible analogy.
And cutting off baby toes is what?