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viddaloo

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Re: Annual Average Thread
« Reply #50 on: December 09, 2014, 12:00:14 PM »
Quote from: Wikipedia
In colloquial language average usually refers to the sum of a list of numbers divided by the size of the list, in other words the arithmetic mean. However, the word "average" can be used to refer to the median, the mode, or some other central or typical value. In statistics, these are all known as measures of central tendency. Thus the concept of an average can be extended in various ways in mathematics, but in those contexts it is usually referred to as a mean (for example the mean of a function).



Let's zoom in on the same graph to the next 12 months, shall we? There we see that the auto–prediction yesterday rather amazingly went from Apr4 to May3 for when the annual volume will go from 5th to 6th lowest. This happened in just one day. The auto is based on weekly gain and how fast that weekly gain will take the annual volume above the current 6th lowest year.

My gut feeling prediction for the next 7 months, however, says we will cross the line somewhere between May 3rd and August 1st. Really, it's amazing that the purple graph has been rising for as long as it has, and 'gravity' should soon pull it back downwards, but likely not until it crosses the pink 2010 line.
« Last Edit: December 09, 2014, 10:10:47 PM by viddaloo »
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viddaloo

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Re: Annual Average Thread
« Reply #51 on: December 11, 2014, 02:14:05 PM »
Daily estimates fluctuate up and down the late–March — early–May blue line, which isn't that strange, as this part of the blue 2007/08 line is pretty much aligned and it doesn't take much in the form of variation to the weekly gain to switch from one side of the spectrum to the other.

I don't think the annual average will ever go higher than the blue line, though. In fact, I think when the AAV finally turns around and goes down again, it will never again be as high as at that turning point. These are probably the very last days/months above 15 k km³.

The only aspect of excitement is how high we will go and how long it will be before the turn.
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crandles

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Re: Annual Average Thread
« Reply #52 on: December 11, 2014, 02:48:47 PM »
Added annual average and more gridlines.

Don't want to put words in your mouth but this seems like what you are proposing. Not impossible to believe that. When 4 people jump to an assumption, is the correct response to blame them for making that assumption or to think maybe your beliefs could be more clearly explained and this is just a suggestion for what you could try.


viddaloo

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Re: Annual Average Thread
« Reply #53 on: December 11, 2014, 02:58:07 PM »
2029, crandles. So your crash dates are off by at least a year.

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crandles

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Re: Annual Average Thread
« Reply #54 on: December 11, 2014, 03:24:47 PM »
2029, crandles. So your crash dates are off by at least a year.

Yes, you are right they are off, my mistake. But then there could well be other things wrong. For instance, there is quite a sharp turn in the max month trend, why would that happen now? Is it supposed to wait until there is a year with no ice before turning? There might also be a few other ways of dealing with that.

As I said I don't want to put words in your mouth so want to see what you think rather than demand that you think what I think you might think. So it was more a sketch of what you could show if you wanted.

viddaloo

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Re: Annual Average Thread
« Reply #55 on: December 11, 2014, 03:35:47 PM »
2029, crandles. So your crash dates are off by at least a year.

Yes, you are right they are off, my mistake. But then there could well be other things wrong. For instance, there is quite a sharp turn in the max month trend, why would that happen now?

Well, the main other things that are wrong are your max and min volume graphs, that you claim that I claim will turn like this. For anyone who reads closely, they'll see I don't say anything about those graphs, only that the total will hit zero in '29 if the choice of trendline is plausible.

So far I've seen no other trendlines attached to the Annual Average graph, so it will be exciting to see if such a suggestion arises, for instance from persons who disagree with my posted choice of trendline. That said, I won't hold my breath!  ;D
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crandles

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Re: Annual Average Thread
« Reply #56 on: December 11, 2014, 05:38:41 PM »

Well, the main other things that are wrong are your max and min volume graphs, that you claim that I claim will turn like this. For anyone who reads closely, they'll see I don't say anything about those graphs, only that the total will hit zero in '29 if the choice of trendline is plausible.

So far I've seen no other trendlines attached to the Annual Average graph, so it will be exciting to see if such a suggestion arises, for instance from persons who disagree with my posted choice of trendline. That said, I won't hold my breath!  ;D

re the first sentence. I didn't show anything about what you thought the min would do. I did make a suggestion about the max which I wanted you to correct assuming that was necessary. (purple line is just a remnant that perhaps should have been deleted.)

Re second sentence. That seems a remarkably different version of event to what I understood before.

Above is a clear conditional on 'if the trendline is plausible' which seems to accept no responsibility for whether the trendline is plausible or not.

That seem to be you distinctly distancing yourself from such a rapid transition prediction.

Contrast that with:

The way I read the data from PIOMAS, it will be a decade tops from the first ice–free day till the first ice–free year.

note that you said "will be" not "might only be"

Oh, it shows what I think it shows, all right!

Is also very definite not conditional.

Posting just the annual average quadratic fit is not enough to show ' it will be a decade tops from the first ice–free day till the first ice–free year.'

Four people have assumed from that graph that it is more likely the average will become less steep when the min reaches zero somewhat like as suggested below rather than the max trend suddenly getting steeper as in the suggested graph previously posted.

I suggest that first you need to decide whether you are claiming there will be a rapid transition or not and make this clear.

If you want to stick to predicting a rapid transition but don't want to predict that the max volume trend will turn sharply steeper then it is hard to understand how you can believe the rapid transition belief and you would need to explain how such positions are not contradictory.

viddaloo

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Re: Annual Average Thread
« Reply #57 on: December 11, 2014, 05:59:14 PM »
I suggest that first you need to decide whether you are claiming there will be a rapid transition or not and make this clear.

Hilarious!

I don't know if you'd call perennial open waters by mid–2029 a rapid transition or not, as obviously I have no access to your line of thinking here. But for what it's worth, I do distance myself and I have distanced myself several times already from the 2029 figure: I think it's much too conservative.
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Peter Ellis

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Re: Annual Average Thread
« Reply #58 on: December 11, 2014, 06:56:08 PM »
Viddaloo: 
What we know at this point is that you are predicting annual average to hit zero around 2029 or before.  From this we can deduce that the winter maximum must also hit zero around 2029 or before.

I think it would help us all if you could draw a graph like crandles' graph, showing all three figures - i.e. summer min, winter max and annual average - making clear what your predictions actually are, and confirming whether you think the implied crash in winter maximum is physically plausible.

At the very least, this will allow us to test your predictions to some extent over the coming few years.


Well, the main other things that are wrong are your max and min volume graphs, that you claim that I claim will turn like this. For anyone who reads closely, they'll see I don't say anything about those graphs, only that the total will hit zero in '29 if the choice of trendline is plausible.
But you are claiming the max volume graph will turn like this - whether you realise it or not!  If the total annual average hits zero in '29, then the max volume must also hit zero in '29, because the average of any positive number plus zero is greater than zero. So, when you claim "the total will hit zero in '29" it is your job to realise what that prediction actually implies, and to evaluate its plausibility based on those implications.

Or are you somehow predicting that the annual average will hit zero before the winter maximum hits zero?  If so, I may have some important information for you about, well, how maths works.

viddaloo

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Re: Annual Average Thread
« Reply #59 on: December 11, 2014, 07:19:00 PM »
LOL! Nice try, guys.

PS: I have enough data and an adequate method to say something about the annual average hitting zero. I don't have that for neither minimum nor maximum, so I just won't speculate. It's funny how guys who deny others the right to speculate freely change back and forth from that and to demanding that others speculate, when they explicitly do not want to speculate. Must be a higher form a logic that I just don't have access to yet!  ;D



PPS:
  • I don't have the day–to–day volume figures for 2015—2029, so therefore I cannot find the maximum and minimum volume for those years.
  • What I do have is twelve thousand data points each made by calculating the centered average for the 365 days around that point, which is more than enough points to base an accurate trendline on.
  • The data I have is adequate for pointing out a plausible collapse year for the annual average, ie a zero point year, and a plausible path/graph down to that zero.
  • The data I have is also adequate for giving a 'deadline' for when min, max and all other days will have gone to zero.
  • That does not mean it's adequate for drawing up a plausible decline path for min, max or any other days on their way to zero.
  • I can say they will be zero by year X without drawing up a decline path, because I can have enough data to say when it will be zero, without having enough data to say how every single date of the year or every single point on the map got there.
  • The arithmetic mean ('average') is the secret weapon for this sort of job, because it cannot be zero if even one single grid block or a single day has a small amount of ice. When it's not zero, I cannot know where that ice is, but when it is zero, I can know the exact amount of ice for every single spot on the map for each day of the year. (Sounds like magic, but isn't. It's just math!)
« Last Edit: December 11, 2014, 08:48:50 PM by viddaloo »
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Peter Ellis

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Re: Annual Average Thread
« Reply #60 on: December 12, 2014, 01:44:25 AM »
You're missing the point again.

I take issue with your (3). Your zero date for the annual average is not remotely plausible, and nor is the path to that zero.

The reason your predicted path to zero is not plausible is because having an annual average of zero necessarily implies an annual maximum of zero.

Therefore, in order for the annual average to follow your predicted path, the winter maximum will have to undergo a much faster drop - and there is absolutely no physical basis for any such prediction.

Like it or not, you are making a prediction about the winter maximum (to wit, that it will be zero on or around 2029), with no evidence and no reasoning. I disagree with you.

I don't think there's any basis in pursuing this further.

crandles

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Re: Annual Average Thread
« Reply #61 on: December 12, 2014, 02:32:20 PM »
You're missing the point again.

Like it or not, you are making a prediction about the winter maximum (to wit, that it will be zero on or around 2029), with no evidence and no reasoning. I disagree with you.

I don't think there's any basis in pursuing this further.

+1


viddaloo

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Re: Annual Average Thread
« Reply #62 on: December 12, 2014, 02:49:09 PM »
You're missing the point again.

I take issue with your (3). Your zero date for the annual average is not remotely plausible, and nor is the path to that zero.

The reason your predicted path to zero is not plausible is because having an annual average of zero necessarily implies an annual maximum of zero.

Yeah, well, I guess I should have written that you should also read my point 4). 'My mistake'. LOL.

I think it would help us all if you could draw a graph like crandles' graph, showing all three figures - i.e. summer min, winter max and annual average - making clear what your predictions actually are, and confirming whether you think the implied crash in winter maximum is physically plausible.

At the very least, this will allow us to test your predictions to some extent over the coming few years.

I agree that being able to test an estimate over the coming years is good. That's why I test my estimate every day, in fact. When I'm posting the zoomed–in annual average graphs, I am publishing those tests. The best thing, however, is probably the fact that you can do this yourself. You can test my estimates every day, if you like, for the coming few years. I've been kind enough to show you how, by detailing my method.

PS: The problem with testing my estimates for winter maximum volume is that I haven't made any. If, on the other hand, I had made such estimates, then you would have been able to test those once a year. Now you are left instead with the possibility to test my average volume assumptions every day of every year.
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viddaloo

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Re: Annual Average Thread
« Reply #63 on: December 13, 2014, 03:17:48 PM »
For the first time in 6 days, the annual average is not closing in 52 km³ on 2007, but 50 km³. But the weekly gain is still 27 km³, so the explanation is 2007 falling slower towards us. In any case, the estimate is now for an April 8th shift from 5th lowest average volume to 6th lowest.

But, as stated before, I think we'll cross the pink 2010 line, and not the blue 2007/8 line, somewhere between May and August. We should soon be getting the first estimates suggesting such a 'pink' crossing instead of the blue.
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viddaloo

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Re: Annual Average Thread
« Reply #64 on: December 14, 2014, 05:42:59 AM »
But, as stated before, I think we'll cross the pink 2010 line, and not the blue 2007/8 line, somewhere between May and August. We should soon be getting the first estimates suggesting such a 'pink' crossing instead of the blue.
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viddaloo

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Re: Annual Average Thread
« Reply #65 on: December 14, 2014, 09:17:33 AM »
Back to the 2029 collapse graph for average volume: We shall have to go through all of these three orange boxes during 2015—2020 for the '29 collapse estimate to be realized. If we don't, the estimate may be considered falsified.

For the lower of the three boxes, this means the annual average needs to go below 10 k km³ within the next five years. The average is currently at 15.2.

Going through all of these three will probably entail some pretty heavy dents to the winter maximum volume during ~2016—2019.
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viddaloo

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Re: Annual Average Thread
« Reply #66 on: December 15, 2014, 05:47:01 PM »
May 11th.
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Unmex Chingon

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Re: Annual Average Thread
« Reply #67 on: December 15, 2014, 11:29:04 PM »
LOL! Nice try, guys.

PS: I have enough data and an adequate method to say something about the annual average hitting zero. I don't have that for neither minimum nor maximum, so I just won't speculate. It's funny how guys who deny others the right to speculate freely change back and forth from that and to demanding that others speculate, when they explicitly do not want to speculate. Must be a higher form a logic that I just don't have access to yet!  ;D


You have enough data and method to say something about annual average hitting Zero, Correct? (just copying your quote)

IF the annual average is close to Zero - does that not imply 365 consecutive days of nearly Zero?  So the Maximum and Minimum would have to be close to Zero every single day of 2029 - am i missing something in my math different than yours?  You don't have to speculate the maximum and minimum if you know annual average is Zero - as those would have to be Zero as well.


viddaloo

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Re: Annual Average Thread
« Reply #68 on: December 16, 2014, 02:58:29 AM »
Correct, Unmex. For the July 17th 2029 zero date, the volume for all days half a year earlier to half a year later would be exactly zero. That makes an arithmetic mean (or average) of 0.0.
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viddaloo

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Re: Annual Average Thread
« Reply #69 on: December 16, 2014, 03:05:19 AM »
Some fairly major news, folks: There is now reason to believe the purple line has already started its long awaited (and likely long–lasting) descent, as ESA's Cryosat program reports a significantly lower sea ice volume for October compared to last year, and a slightly lower volume for November compared to last. See the PIOMAS thread for more detail.

This means that this graph should probably be targeting the orange 2014 line instead of the pink 2010 line, that is if annual volume isn't already lower than it was about 12 months ago:

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viddaloo

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Re: Annual Average Thread
« Reply #70 on: December 16, 2014, 05:48:53 AM »
Quote
«Between autumn 2010 and spring 2013, there was a 14% and 5% reduction in autumn and spring Arctic sea ice volume, respectively, in keeping with the long-term decline in extent.»
Autumn 2010 to autumn 2012: 14% drop in sea ice volume.
Spring 2011 to spring 2013: 5% drop in sea ice volume.

Quote
«However, since then there has been a marked 41% and 9% recovery in autumn and spring sea ice volume, respectively, more than offsetting losses of the previous three years.»
Autumn 2012 to autumn 2014: 41% increase in sea ice volume.
Spring 2013 to spring 2014: 9% increase in sea ice volume.

Add to that a 15% drop in reported October sea ice volume from 2013 to 2014 and a 6% drop by 1st or 15th December from 2013, and you have a picture of an annual average ice volume that clearly peaked somewhere between 'spring' 2014 (still up 9% over the previous year) and October 2014 (down 15%), and that is very different from the PIOMAS AAV depicted here:
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Unmex Chingon

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Re: Annual Average Thread
« Reply #71 on: December 16, 2014, 04:28:24 PM »
Correct, Unmex. For the July 17th 2029 zero date, the volume for all days half a year earlier to half a year later would be exactly zero. That makes an arithmetic mean (or average) of 0.0.

Wow!  Your belief is that in 15 years - all through the winter - the arctic will be enjoying warm weather so that NO ice will form or refreeze.   8)

jdallen

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Re: Annual Average Thread
« Reply #72 on: December 16, 2014, 06:12:47 PM »
Correct, Unmex. For the July 17th 2029 zero date, the volume for all days half a year earlier to half a year later would be exactly zero. That makes an arithmetic mean (or average) of 0.0.

Wow!  Your belief is that in 15 years - all through the winter - the arctic will be enjoying warm weather so that NO ice will form or refreeze.   8)
Unmex, I think you'll find that's an extreme minority opinion on the board here, and Vidd is leading you into a trap.  He's suggesting for the July 17 date calculation to be *true*, the numbers would need to line up as he suggests.  Whether he believes we'll have weather which will support year-round ice-free conditions is a separate question.


This space for Rent.

viddaloo

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Re: Annual Average Thread
« Reply #73 on: December 16, 2014, 09:12:23 PM »
No trap, JD. I'm just explaining grown–up human beings how zero divided by 365 is zero. Strangely, people take weeks on end to understand how 0/x = 0, and sound like they want to burn your house down because you've acquired the secret mathematical knowledge of calculating an average.

PS: Of course, with the data from Cryosat, we're looking at a much earlier collapse year than 2029.
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Peter Ellis

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Re: Annual Average Thread
« Reply #74 on: December 16, 2014, 09:42:48 PM »
No trap, JD. I'm just explaining grown–up human beings how zero divided by 365 is zero. Strangely, people take weeks on end to understand how 0/x = 0, and sound like they want to burn your house down because you've acquired the secret mathematical knowledge of calculating an average.

No, that's the exact opposite of the truth.  Various people on this board have been pointing out to you the fact that zero average implies zero max, and asking - initially politely and later more sarcastically - whether (a) you really meant to make that prediction, and (b) you had any evidence at all to justify it.  After all, it's hard to credit that anyone would be that naive, so we gave you the benefit of the doubt.

However, we've now established that the answers are (a) yes, and (b) no, so we're ignoring you except when you're in danger of confusing other people. Or at least, that's what I'm doing.

ChrisReynolds

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Re: Annual Average Thread
« Reply #75 on: December 16, 2014, 09:45:45 PM »
No trap, JD. I'm just explaining grown–up human beings how zero divided by 365 is zero. Strangely, people take weeks on end to understand how 0/x = 0, and sound like they want to burn your house down because you've acquired the secret mathematical knowledge of calculating an average.

No, that's the exact opposite of the truth.  Various people on this board have been pointing out to you the fact that zero average implies zero max, and asking - initially politely and later more sarcastically - whether (a) you really meant to make that prediction, and (b) you had any evidence at all to justify it.  After all, it's hard to credit that anyone would be that naive, so we gave you the benefit of the doubt.

However, we've now established that the answers are (a) yes, and (b) no, so we're ignoring you except when you're in danger of confusing other people. Or at least, that's what I'm doing.

Ditto.

viddaloo

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Re: Annual Average Thread
« Reply #76 on: December 16, 2014, 09:53:29 PM »
Correct, Unmex. For the July 17th 2029 zero date, the volume for all days half a year earlier to half a year later would be exactly zero. That makes an arithmetic mean (or average) of 0.0.

Wow!  Your belief is that in 15 years - all through the winter - the arctic will be enjoying warm weather so that NO ice will form or refreeze.   8)

No, Unmex. I know this is very hard for you, so I'll explain this very slowly: I'm saying after all your questions about very, very simply things if you know what a calculator is, that an annual average volume of zero in July 2029 would require all 365 days around that date to have zero volume. Somehow that's very, very hard for you to understand, so you keep asking, and keep asking, and when you finally get it, you dream up some story about warm weather every day, which you then suppose is my story, because it's your story.

I've said time and time again that I personally don't believe this will happen in 2029. I think it will happen much earlier. The recent data from the AGU also seems to suggest a year closer to the mid–twenties.
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Unmex Chingon

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Re: Annual Average Thread
« Reply #77 on: December 16, 2014, 09:59:21 PM »
No trap, JD. I'm just explaining grown–up human beings how zero divided by 365 is zero. Strangely, people take weeks on end to understand how 0/x = 0, and sound like they want to burn your house down because you've acquired the secret mathematical knowledge of calculating an average.

PS: Of course, with the data from Cryosat, we're looking at a much earlier collapse year than 2029.

I will continue for a little - since this is not a trap.

The math part I get - I know the formula.  My question is not regarding the formula calculation but the fact that variable X has to be Zero.  X/365=0 so  viddaloo - it is your prediction that X will be zero by 2029 or now even sooner?  Does viddaloo believe X will be zero in 2029 or sooner?  Does viddaloo thinks for 365 straight days Arctic sea ice will not exist around 2029?

ChrisReynolds

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Re: Annual Average Thread
« Reply #78 on: December 16, 2014, 10:06:05 PM »
Correct, Unmex. For the July 17th 2029 zero date, the volume for all days half a year earlier to half a year later would be exactly zero. That makes an arithmetic mean (or average) of 0.0.

Wow!  Your belief is that in 15 years - all through the winter - the arctic will be enjoying warm weather so that NO ice will form or refreeze.   8)

No, Unmex. I know this is very hard for you, so I'll explain this very slowly: I'm saying after all your questions about very, very simply things if you know what a calculator is, that an annual average volume of zero in July 2029 would require all 365 days around that date to have zero volume. Somehow that's very, very hard for you to understand, so you keep asking, and keep asking, and when you finally get it, you dream up some story about warm weather every day, which you then suppose is my story, because it's your story.

I've said time and time again that I personally don't believe this will happen in 2029. I think it will happen much earlier. The recent data from the AGU also seems to suggest a year closer to the mid–twenties.

ROFLMAO.

Thanks Viddaloo, I always like to have a good laugh before bedtime, you just had me hooting.  ;D

Sorry for breaking my policy of no comment, but there's only so much a man can take. The only  alternative would have been to PM various people, and I don't like talking behind people's backs.

Back to no comment. :-X

viddaloo

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Re: Annual Average Thread
« Reply #79 on: December 16, 2014, 11:22:49 PM »
If you average the official sea ice volume numbers on a 365–day basis this is what you get. Just add a trendline and voila; July 2029.

Any person with a basic skill in math anywhere in the world could repeat this and get the exact same result. So your beef is really with math, not with me as a person.
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Peter Ellis

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Re: Annual Average Thread
« Reply #80 on: December 17, 2014, 12:06:58 AM »
Viddaloo:  There are many trendlines you can fit to the data - quadratic ones, exponential ones, cubic ones, higher order polynomials, logarithmic ones, Gompertz ones, etc...

All of these will fit the data equally well, but give very different predictions.  If you want us to take your predictions seriously, you have to explain why you have chosen the type of trendline you have.  The equation of that trendline implies some kind of model for how ice is formed and lost.  Different types of trendline may be more or less plausible, depending on the types of physical model implied by each trendline.

Yours is incredibly implausible.

Peter Ellis

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Re: Annual Average Thread
« Reply #81 on: December 17, 2014, 01:29:24 AM »
Further comment:

You have projected a trendline based on average yearly volume.  From this you predict an average yearly volume of zero before 2029, and from that deduce that the yearly maximum volume will have to undergo an unprecedented crash (through unidentified mechanisms).

You could equally well project a trendline based on winter max volume, from which you would predict a yearly max volume of zero some time around ~2040, and from that deduce that the drop rate of the yearly average volume will have to level off some time between now and then.

What leads you to favour one over the other?  Why is a naive extrapolation of yearly average volume so much more credible to you than a naive extrapolation of winter maximum volume?  Why are both of these so much more credible to you than predictions grounded in real understanding and modelling of the relevant physics?

viddaloo

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Re: Annual Average Thread
« Reply #82 on: December 17, 2014, 02:17:14 AM »
  • I don't have the day–to–day volume figures for 2015—2029, so therefore I cannot find the maximum and minimum volume for those years.
  • What I do have is twelve thousand data points each made by calculating the centered average for the 365 days around that point, which is more than enough points to base an accurate trendline on.
  • The data I have is adequate for pointing out a plausible collapse year for the annual average, ie a zero point year, and a plausible path/graph down to that zero.
  • The data I have is also adequate for giving a 'deadline' for when min, max and all other days will have gone to zero.
  • That does not mean it's adequate for drawing up a plausible decline path for min, max or any other days on their way to zero.
  • I can say they will be zero by year X without drawing up a decline path, because I can have enough data to say when it will be zero, without having enough data to say how every single date of the year or every single point on the map got there.
  • The arithmetic mean ('average') is the secret weapon for this sort of job, because it cannot be zero if even one single grid block or a single day has a small amount of ice. When it's not zero, I cannot know where that ice is, but when it is zero, I can know the exact amount of ice for every single spot on the map for each day of the year. (Sounds like magic, but isn't. It's just math!)
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Unmex Chingon

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Re: Annual Average Thread
« Reply #83 on: December 17, 2014, 03:31:55 AM »
If you average the official sea ice volume numbers on a 365–day basis this is what you get. Just add a trendline and voila; July 2029.

Any person with a basic skill in math anywhere in the world could repeat this and get the exact same result. So your beef is really with math, not with me as a person.

What does you trendline state the avg will be from 2029 to 2040?

Peter Ellis

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Re: Annual Average Thread
« Reply #84 on: December 17, 2014, 10:10:18 AM »
1)  You could easily get it.  Other people here have been plotting it.  If you asked nicely, I'm sure they'd tell you where to find it.

2) a) If I collected 12,000 points by measuring the Arctic extent every 15 minutes from April through July, I would get a very nice trend forecasting a melt-out some time in about November.  Would this be accurate?  No, because it would not be grounded in physics.  The Earth has a yearly cycle which means that naively forecasting a trend is not necessarily a good predictor of the future.  There may or may not be cycles in average yearly extent: there are _certainly_ physical factors which you are ignoring that will alter the shape of the trendline for average yearly extent.

2) b) As previously stated, there are many different trendlines you could fit to your 12,000 points, with completely different results.  Why have you chosen exponential (or was it quadratic) ahead of Gompertz, say?

3+4) No it isn't, for reasons we're trying to explain to you.

5) Finally something we can agree on!

6) No, you can't.  Well, you can say it, but that doesn't make you right, or even plausible.

7) Being revoltingly patronising doesn't exactly help your cause.  We all know what an average is.

viddaloo

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Re: Annual Average Thread
« Reply #85 on: December 17, 2014, 03:48:03 PM »
Amid suggestion the purple graph could be already dropping, like the green graph, the target is now moving down the pink graph from May 13th to May 16th. But we could just as well be looking at the orange graph from below. Will we ever know, and how soon will we grow accustomed to the deafening silence?
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viddaloo

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Re: Annual Average Thread
« Reply #86 on: December 18, 2014, 06:42:23 AM »
In just one week from December 11th to yesterday, the 17th, the target (for crossing the line to 6th lowest) has moved all the way from March 29th on the blue line to May 18th on the pink one.



It will be interesting to see how far down the line it will finally go, and whether it could instead cross the orange graph into 4th lowest instead of 6th.
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jai mitchell

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Re: Annual Average Thread
« Reply #87 on: December 18, 2014, 08:59:21 PM »
Haiku of Past Futures
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viddaloo

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Re: Annual Average Thread
« Reply #88 on: December 19, 2014, 04:38:43 AM »
I have a question Mr. Vid,

When do you think that lake superior will move into perpetual ice free 365 averages?

I have absolutely no data on Lake Superior, dude  ;D

I dunno why you would expect that.
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viddaloo

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Re: Annual Average Thread
« Reply #89 on: December 19, 2014, 04:39:44 AM »
Target moving on down to May 19th.
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jai mitchell

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Re: Annual Average Thread
« Reply #90 on: December 19, 2014, 06:11:44 PM »
That is a pathetic copout,

either you think that the arctic has a much higher likelihood of a perpetual ice free state than lake superior or you don't.

And if you hold an unfounded belief that the arctic will move to equitable temperatures in 2029 then reason follows that Lake Superior would also experience this change in temperature regime at or before this time.

It makes me a bit sad to see you post such nonsense on this board.

you can't have an annual average of zero until you have a winter maximum of zero.  If you don't get this. . .well then maybe you should revisit some basic arithmetic classes, I suggest 10th year finishing school.

http://lmgtfy.com/?q=calculating+the+mean&l=1

unless you can magically come up with a negative value for daily sea ice volume, I suggest you revisit your calculus.
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viddaloo

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Re: Annual Average Thread
« Reply #91 on: December 19, 2014, 06:25:30 PM »
Well, merry Christmas to you too, Jai!

First, the Lake Superior is a lake. The name is really a giveaway here. It wouldn't be called Lake Superior by almost everyone if it wasn't a lake.

Being a lake means it's not connected to the warming ocean. Thus the ocean may warm without the lake warming much.

Apart from that, I thought everyone had now got the point I've stressed several times about all 365 days surrounding the estimated date for ice–free year by definition needing to have zero volume. I have not made an exception for April days or September days. Thus max and min must of course also be zero.

Please take the time to read what I write before launching such pathetic attacks. Thank you  ;D
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ChrisReynolds

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Re: Annual Average Thread
« Reply #92 on: December 19, 2014, 06:27:54 PM »
Viddaloo,

So that you can have some ammunition to oppose Jai's allegation of a cop-out, here is the April Volume for Hudson Bay. April is the month of peak volume, so for Hudson Bay to be ice free one need only look at when Hudson bay is ice free in April.

Year  Volume (k km^3)
1978   1.809
1979   1.799
1980   1.730
1981   1.701
1982   1.824
1983   1.859
1984   1.938
1985   1.891
1986   1.817
1987   1.805
1988   1.787
1989   1.911
1990   1.943
1991   1.956
1992   1.988
1993   1.968
1994   2.002
1995   1.895
1996   1.895
1997   2.004
1998   1.922
1999   1.684
2000   1.704
2001   1.736
2002   1.871
2003   1.931
2004   1.768
2005   1.814
2006   1.739
2007   1.634
2008   1.741
2009   1.828
2010   1.380
2011   1.649
2012   1.595
2013   1.765
2014   2.033

Q1) When does your trend extrapolation reach zero?

Q2) Why is this different from the Arctic Ocean?

A good place to start would be to look at volume from ice above and below 2.2m thick in April for the Arctic Ocean (not the seas outside the Arctic Ocean).

Year   <2.2m   >2.2m
4/1978   4.802   24.467
4/1979   4.544   24.774
4/1980   4.001   24.319
4/1981   5.104   22.055
4/1982   6.598   18.385
4/1983   6.072   20.016
4/1984   6.156   19.886
4/1985   5.112   21.589
4/1986   5.517   21.789
4/1987   4.920   23.003
4/1988   4.870   22.638
4/1989   6.600   20.067
4/1990   6.440   19.587
4/1991   5.639   21.243
4/1992   6.242   19.553
4/1993   5.539   20.956
4/1994   5.568   20.045
4/1995   5.459   19.203
4/1996   7.693   16.430
4/1997   7.034   18.471
4/1998   5.777   19.641
4/1999   5.336   19.194
4/2000   6.891   16.661
4/2001   7.128   16.881
4/2002   8.609   15.093
4/2003   8.743   14.945
4/2004   9.586   12.947
4/2005   8.425   14.234
4/2006   7.167   14.516
4/2007   9.988   10.302
4/2008   11.076   10.066
4/2009   12.211   9.032
4/2010   8.898   11.906
4/2011   12.678   6.647
4/2012   9.111   10.278
4/2013   12.407   7.150
4/2014   12.587   6.702

Q3) With regards the loss of volume that gives rise to the exponential loss you are extrapolating to give a year round sea ice free state before 2029:

Where is this volume loss coming from?
a) From all thicknesses of ice.
b) From ice below 2.2m thick.
c) From ice above 2.2m thick.

Q4) What does the behaviour of ice above and below 2.2m thick tell us about the future of the exponential trend of loss of winter volume?

Q5) In view of the above data, why would one expect radically different profiles of loss between the Arctic Ocean and a seasonal ice pack such as Hudson Bay (or Lake Superior).



Thanks Jai, that was a very intelligent angle you used. I spotted what you were getting at as soon as you posted, so it was not unreasonable to expect it to be understood and to be straightly addressed.

viddaloo

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Re: Annual Average Thread
« Reply #93 on: December 19, 2014, 06:33:23 PM »
Merry Christmas to you too, CR.

I don't want to sound boring, but I suggest you two go ahead and create a new thread about the inland lakes of North America, where your posts will be more on–topic.

This thread is about annual averages for the Arctic sea ice, it's posted in the Arctic sea ice forum and generally concerns matters related to Arctic sea ice.

Therefore, should you have a burning issue on your mind concerning something other than Arctic sea ice, I suggest you post it elsewhere. That way we can focus more in this thread on annual averages of the Arctic sea ice.
« Last Edit: December 19, 2014, 06:48:01 PM by viddaloo »
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ChrisReynolds

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Re: Annual Average Thread
« Reply #94 on: December 19, 2014, 06:34:58 PM »
I see an errant reliance on warming oceans is being made. If this is seen as a problem, here is Bering Sea March volume (March being the peak volume for Bering Sea).

393.881
264.152
441.839
408.697
268.870
447.083
500.402
327.796
427.384
432.688
475.580
170.865
558.116
502.564
570.366
388.179
457.388
492.380
225.962
359.942
458.874
492.491
372.084
217.526
417.706
284.063
301.725
272.981
404.980
473.026
607.092
409.370
557.639
260.688
644.290
533.281
301.837

You can easily substitute that for Hudson in the above post.

jai mitchell

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Re: Annual Average Thread
« Reply #95 on: December 20, 2014, 12:24:24 AM »
however,

even if the summer sea ice minimum reaches zero around  2020-2025 and we start experiencing august minimums of zero by 2029.  This will cause profound changes in Jetstream and associated weather disruptions throughout the northern hemisphere.

So maybe vid is right in context, though not in scope.

All things being equal, when we start seeing august 15th sea ice minimums, there will be hell to pay for consistent water and agriculture resources for about 85% of the Human population.
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ChrisReynolds

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Re: Annual Average Thread
« Reply #96 on: December 20, 2014, 06:16:17 PM »
Jai,

I know we still disagree on the implications of autumn volume increase in response to low sea ice in summer. I had hoped that this would mean you'd have more success with Viddaloo, it seems not.

However none of the above pre-supposes a long tail. The above observations were factors in my previous opinion that we'd see a fast transition in the 2020s. As for the impact of autumn/winter growth, I think we'll just have to agree to disagree as we see what happens.

viddaloo

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Re: Annual Average Thread
« Reply #97 on: December 20, 2014, 08:37:31 PM »
Though the daily gain is highest since December 15th, target's still moving south: May20.
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ChrisReynolds

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Re: Annual Average Thread
« Reply #98 on: December 20, 2014, 08:59:48 PM »
Merry Christmas to you too, CR.

I don't want to sound boring, but I suggest you two go ahead and create a new thread about the inland lakes of North America, where your posts will be more on–topic.

This thread is about annual averages for the Arctic sea ice, it's posted in the Arctic sea ice forum and generally concerns matters related to Arctic sea ice.

Therefore, should you have a burning issue on your mind concerning something other than Arctic sea ice, I suggest you post it elsewhere. That way we can focus more in this thread on annual averages of the Arctic sea ice.

So you edited it to add a load of waffle.

Jai is correct, you have no interest in open discussion so it's back to ignoring you, you have nothing of value to add to this forum. Anyone with average intelligence and average understanding of sea ice would have got why Jai posted the reference to Lake Superior. You didn't get it, and when presented with the chance to think critically you ran away (again).

By the way, 5 year cycle?

2007 1
2008 2
2009 3
2010 4
2011 5
2012 And there we have the five year cycle.

But as the events of 2007 and 2012 occured due to seperate processes, the only underlying causal factor being the overall thinning of the ice, there is no five year cycle. It is as meaningless as your curve extrapolation.

How about you keep this thread as the one where you talk to yourself to avoid impairing the other threads? Especially with the meaningless and incomprehensible graphs you keep posting, as above.

viddaloo

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Re: Annual Average Thread
« Reply #99 on: December 21, 2014, 08:36:26 PM »
Moving on down to May 21st.
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