Support the Arctic Sea Ice Forum and Blog

Poll

What do you think of the IPCC definition: "Nearly ice-free conditions is when sea ice extent is less than 1 million km2 for at least five consecutive years"?

It is a good definition.
7 (24.1%)
It is misleading, because it makes you feel that there is time to react, while the true is that the Arctic sea ice is going to collapse in the near future.
15 (51.7%)
Other.
7 (24.1%)

Total Members Voted: 28

Voting closed: June 03, 2016, 07:19:27 AM

Author Topic: IPCC AR5 Definition of "Nearly ice-free conditions"  (Read 14413 times)

Juan C. García

  • Nilas ice
  • Posts: 1390
    • View Profile
  • Liked: 390
  • Likes Given: 479
IPCC AR5 Definition of "Nearly ice-free conditions"
« on: May 24, 2016, 07:19:27 AM »
Do you think that it is unacceptable that the IPCC developed this kind of ice-free definition? Should they changed it immediately?
It will be good if you write us a comment.
« Last Edit: May 24, 2016, 07:32:33 AM by Juan C. García »
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

sesyf

  • New ice
  • Posts: 47
    • View Profile
  • Liked: 2
  • Likes Given: 30
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #1 on: May 24, 2016, 01:12:35 PM »
Does that definition sort (5 years in row) sort of ignore the variability of ice cover etc - winters will rebuild the ice for a long time (at least one year.... ;) ) and the following year could have weather that changes the melt rate to 1.1 million or greater in September... so bit more flexible definition might be better?

theoldinsane

  • New ice
  • Posts: 66
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #2 on: May 24, 2016, 01:58:45 PM »
I think 1 million km2 is ok, but maybe a 5 year moving average  for the Daily minima would be better?

magnamentis

  • Guest
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #3 on: May 24, 2016, 02:17:11 PM »
any use of terms that are not straight forward is wrong IMO. in this case we are dealing with the useless term "nearly icefree" and it's  meaningless definition. facts do not have to be defined. as long as we have ice we measure as it is in km2 and km3, extent, area and volume. the only meaningful term that matters is "ice free" and that does speak for itself, icefree is no ice at all.

for any other scenario it's absolutely sufficient to deal with common numbers like for example 100'000km2 of ice, that's telling the entire story without need for a new term and new definition that has to be defined and hence will be defined in different manners and hence will lead to back and forth debates about the term itself and absorb time and energy that would be better used to debate solutions.
« Last Edit: May 30, 2016, 07:39:02 PM by magnamentis »

Juan C. García

  • Nilas ice
  • Posts: 1390
    • View Profile
  • Liked: 390
  • Likes Given: 479
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #4 on: May 24, 2016, 03:01:17 PM »
I will present my full arguments in a couple of days, but of course that it is misleading. I believe that the political leaders recieve a lot of information at the UN COPs, but the problem is that the official information continues to talk about Arctic sea ice melting at 2100, so they feel confidence. That is a lousy trick, coming directly from IPCC, that puts the planet on danger.

The true is that we have passed the point of no return. IPCC tries to ignore that.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

timallard

  • Frazil ice
  • Posts: 136
  • designer
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #5 on: May 24, 2016, 03:30:04 PM »
Consider the impacts already seen to walrus being forced to swim to feeding grounds & the bears localizing to refugia where conditions are still ok what kills the adolescents are giant leads to swim.

So, the ice is today too little for biological sustainability, thus this to me this is so small to be incredibly misleading if not criminal at this point in the game, it's too unrealistic to expect anything short of a biological disaster at that areal extent.

They need to include the ecological effects to sea-mammals, fish & birds along with the permafrost melt by then for people & infrastructure to put out a number so low.

Call for an EIS on scenarios from them and a geophysical analysis to put metrics on the permafrost extent change by the time the ice is that small to get an estimate on total damages a tho't.
« Last Edit: May 24, 2016, 03:36:25 PM by timallard »
-tom

Juan C. García

  • Nilas ice
  • Posts: 1390
    • View Profile
  • Liked: 390
  • Likes Given: 479
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #6 on: May 24, 2016, 03:42:03 PM »
The definition: "less than 1 million km2 for at least five consecutive year" is the only way to have models with the following behaivor:
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Laurent

  • Young ice
  • Posts: 2535
    • View Profile
  • Liked: 5
  • Likes Given: 23
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #7 on: May 24, 2016, 05:06:29 PM »
I think they take too much confidence in a Gompertz equation, thought there is some scientific arguments about that. We have put to much false bet in the climate to go on like this. IPCC is there to inform the politics and the citizens, then they should not step in the least drama but enact the worst scenarios, the one we don't want to pass at all cost. As you said it , it is too late, but it is not a reason to continue. We know that the trend is worse than any of their scenarios, from them it is just outrageous, they should endure legal action ! As scientific you must push them so that the average of their scenario follow the trend. The definition should not be averaged on 5 years because it may delay action again, and we don't have time (thought there is some scientific arguments for that also)... if we want to survive (future generations).
« Last Edit: May 24, 2016, 08:20:30 PM by Laurent »

timallard

  • Frazil ice
  • Posts: 136
  • designer
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #8 on: May 24, 2016, 06:58:09 PM »
Correctly interpreting new conditions of sea-ice by satellite data, another Ted Cruzer??

This is at-sea recent work taking ice-cores on sea-ice from UW-APL, a new finding when another researcher sailing north into the Beaufort Sea encountered this "rotten ice", a new form not known to anyone.

The other newbie pancake ice as first forming, never happened like this before to Inuit afaik, commented on elsewhere.

These 3 videos cover this:
"Assessing the Habitability and Physical Structure of Rotting First-year Arctic Sea Ice"; UW-APL research; 6:38;

"ARCTIC SEA STATE: Pancake ice; UW-APL research";5:12 ;

"2010 Arctic Ice Update: Beaufort Sea research vignette 3:10"; 9:49;
-tom

ritter

  • Grease ice
  • Posts: 541
    • View Profile
  • Liked: 5
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #9 on: May 24, 2016, 07:15:55 PM »
I think "nearly ice-free" should reflect a one year event, not wait around for five consecutive years as if we can put the genie back in the bottle. If we hit it once, it is a very clear dead canary. Five-year consecutive is more of an indication of a totally collapsed Arctic rather than "nearly ice-free".

DoomInTheUK

  • Frazil ice
  • Posts: 221
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #10 on: May 25, 2016, 01:53:06 PM »
I see Nearly Ice Free as a statement that the Acrtic we knew is in effect no more.

Once we get to the 'less than 1 million km2' position, it's fairly obvious where it's heading. The trend is unambiguous. Waiting for 5 years to confirm that it's not coming back is more than just erring on the side of caution, it's bordering on denial.

Juan C. García

  • Nilas ice
  • Posts: 1390
    • View Profile
  • Liked: 390
  • Likes Given: 479
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #11 on: May 25, 2016, 02:10:18 PM »
Waiting for 5 years to confirm that it's not coming back is more than just erring on the side of caution, it's bordering on denial.

I agree.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Juan C. García

  • Nilas ice
  • Posts: 1390
    • View Profile
  • Liked: 390
  • Likes Given: 479
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #12 on: May 25, 2016, 02:12:18 PM »
Would you believe that this two graphs could mean something completely different?

1. Would you believe that the first one means that reality exceeds expectations and that "is probably that we will have an ice-free Arctic on the first half of the 21th Century"?

2. While the second one means that "the RCP2.6 emission scenario would imply a high probability that the complete loss of Arctic summer sea ice can still be avoided."?
« Last Edit: May 25, 2016, 02:20:08 PM by Juan C. García »
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Neven

  • Administrator
  • First-year ice
  • *****
  • Posts: 7069
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 651
  • Likes Given: 432
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #13 on: May 25, 2016, 02:34:21 PM »
I wrote about this back in March.

Image September being ice-free four years in a row, but then the fifth year it isn't. IPCC: Arctic not ice-free?  :D  ::)
Il faut comparer, comparer, comparer, et cultiver notre jardin

Laurent

  • Young ice
  • Posts: 2535
    • View Profile
  • Liked: 5
  • Likes Given: 23
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #14 on: May 25, 2016, 02:36:12 PM »
First we should not look at SIA but volume. The loss of volume is much more important compared to the 70' than SIA. Even looking at it, these two graphs show the same thing, the expectations do not fit the reality so models should adapt (that doesn't work the other way).
« Last Edit: May 25, 2016, 05:27:41 PM by Laurent »

timallard

  • Frazil ice
  • Posts: 136
  • designer
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #15 on: May 25, 2016, 04:47:19 PM »
NASA can measure thickness directly using two radars one reflects the ice the other the water below it so gains the difference from the air ... thus volume is rather exact now over the entire area versus previous estimates from like 2009-2010.

Vignette on rotten ice by Barber.

-tom

Acts5v29

  • New ice
  • Posts: 44
    • View Profile
    • worshipJehovah.org - not associated with any religion
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #16 on: May 30, 2016, 05:50:57 PM »
Respectfully to this kind of thinking from IPCC and others, there is a time and a place for catagorising data, and there is a time and a place to state the obvious in clear and blunt terms for those who would otherwise just juggle with the definitions.  It would not harm any scientist to be so blunt - it might even be a valid measure of how serious the situation is.

Juan C. García

  • Nilas ice
  • Posts: 1390
    • View Profile
  • Liked: 390
  • Likes Given: 479
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #17 on: May 30, 2016, 06:54:42 PM »
How much longer for this 2016 lead to be maintained before it becomes apparent we are heading for an historic finish?

Well, the CFSv2 (http://www.cpc.ncep.noaa.gov/products/CFSv2/CFSv2seasonal.shtml) says never, calling instead for this season's large, negative sea ice anomaly to all but disappear entirely over the next two months, with August and September actually coming in *above* climatology:

Of course, the Arctic is in an unstable transitional period, and weird things have happened. But, still, I'll be surprised and amazed--and more than a little relieved--if the CFS comes to pass...

I wrote about this back in March.

Image September being ice-free four years in a row, but then the fifth year it isn't. IPCC: Arctic not ice-free?  :D  ::)

From my point of view, there are several official sites that they continue to be completly misleading. If NOAA has a site that forecast 6+ million for September 2016, it is an official site that it is misleading, but it is not the only one.

The NSIDC graphs that only look at extent, not volume, but they made a trend and then implicity they make a forecast on when there is going to be an ice-free Arctic, are others that are misleading.

And of course, it seems that is politically easier to change the definition of ice-free Arctic, from less than one million km2 in extent, to 5 consecutive years with the same definition, than to recognize that the IPCC models are wrong in general.

We have to say it loud and clear, the new IPCC definition of ice-free Arctic is unacceptable!
« Last Edit: May 30, 2016, 07:02:36 PM by Juan C. García »
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

timallard

  • Frazil ice
  • Posts: 136
  • designer
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #18 on: May 30, 2016, 10:55:38 PM »
Respectfully to this kind of thinking from IPCC and others, there is a time and a place for catagorising data, and there is a time and a place to state the obvious in clear and blunt terms for those who would otherwise just juggle with the definitions.  It would not harm any scientist to be so blunt - it might even be a valid measure of how serious the situation is.
There is much evidence that the sea-ice we see is a remnant at this time of the Holocene, a new form of ice to the Inuit and scientific community, "rotten", over most of the Beaufort unknowing the rest.
-tom

Acts5v29

  • New ice
  • Posts: 44
    • View Profile
    • worshipJehovah.org - not associated with any religion
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #19 on: May 31, 2016, 09:28:45 AM »
That sounds more informative than defining a 5-year period for an ice-free Arctic

abbottisgone

  • Frazil ice
  • Posts: 297
  • "...I'm a rock'n'roll star,...... YES I ARE!!!!!!"
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #20 on: May 31, 2016, 10:01:40 AM »
I have no beef with the definitions of science. It's just nomenclature.

It is not up to the IPCC to tell people how to react: they just deliver the facts and their job ends exactly there.

You don't call your local department of Agriculture and ask them how to be a farmer that makes more cash than the bloke next door.. you ask them for advice on specific things that are supported by documented evidence.
..
But I left school and grew my hair
They didn't understand
They wanted me to be respected as
A doctor or a lawyer man
But I had other plans..........

abbottisgone

  • Frazil ice
  • Posts: 297
  • "...I'm a rock'n'roll star,...... YES I ARE!!!!!!"
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #21 on: May 31, 2016, 10:06:51 AM »
First we should not look at SIA but volume. The loss of volume is much more important compared to the 70' than SIA. Even looking at it, these two graphs show the same thing, the expectations do not fit the reality so models should adapt (that doesn't work the other way).
Cetainly, volume is the most important statistic in the end!
..
But I left school and grew my hair
They didn't understand
They wanted me to be respected as
A doctor or a lawyer man
But I had other plans..........

abbottisgone

  • Frazil ice
  • Posts: 297
  • "...I'm a rock'n'roll star,...... YES I ARE!!!!!!"
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #22 on: May 31, 2016, 10:10:02 AM »
Waiting for 5 years to confirm that it's not coming back is more than just erring on the side of caution, it's bordering on denial.

I agree.
Basically: the world will be in Anarchy exactly 2 seconds after the ice drops below 1 million, guaranteed!
..
But I left school and grew my hair
They didn't understand
They wanted me to be respected as
A doctor or a lawyer man
But I had other plans..........

6roucho

  • Frazil ice
  • Posts: 296
  • Finance geek
    • View Profile
  • Liked: 0
  • Likes Given: 1
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #23 on: May 31, 2016, 06:41:32 PM »
I can't make up my mind about this. If it really is tinkering with definitions to avoid having to declare the Arctic ice-free then that's obviously unacceptable, and brazenly so. On the other hand we should have a naming convention that can absorb outliers. The problem with this one is that it introduces a new outlier on the other side.

Actually I've made up my mind: it's nonsense.

magnamentis

  • Guest
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #24 on: May 31, 2016, 06:51:12 PM »
Waiting for 5 years to confirm that it's not coming back is more than just erring on the side of caution, it's bordering on denial.

I agree.
Basically: the world will be in Anarchy exactly 2 seconds after the ice drops below 1 million, guaranteed!

and i tell you that exactly nothing more than a few headlines will happen. if that what you say were true it would have happened many times already, the 1M mark is just another news for the average citizen and those who understand and could have acted upon facts obviously can't or don't want.

soon we shall see what really will happen but, and i rarely do that, i bet that i'm right here while it does not matter who is right, hence correcting to, it will happen as i say LOL, nothing out of the ordinary will happen before "close to zero event" and 1M is a big number for the public consciousness, the meaning will elude them.

Juan C. García

  • Nilas ice
  • Posts: 1390
    • View Profile
  • Liked: 390
  • Likes Given: 479
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #25 on: June 01, 2016, 08:43:57 AM »
Voting closes in two days, so it will be great if you give your vote!  ;)
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

timallard

  • Frazil ice
  • Posts: 136
  • designer
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #26 on: June 09, 2016, 09:03:32 PM »
any use of terms that are not straight forward is wrong IMO. in this case we are dealing with the useless term "nearly icefree" and it's  meaningless definition. facts do not have to be defined. as long as we have ice we measure as it is in km2 and km3, extent, area and volume. the only meaningful term that matters is "ice free" and that does speak for itself, icefree is no ice at all.

for any other scenario it's absolutely sufficient to deal with common numbers like for example 100'000km2 of ice, that's telling the entire story without need for a new term and new definition that has to be defined and hence will be defined in different manners and hence will lead to back and forth debates about the term itself and absorb time and energy that would be better used to debate solutions.
>> Reacting to, "the useless term "nearly icefree" and it's meaningless definition", along with if it is defined you get mess.

The thought is using the remote-sensing data now available with an albedo-loss quotient tied to the current conditions of the ice, immediate recognition of the change to "rotten ice" new to the Inuit, new to science indicating a change of state.

Barber reports open-area increasing in all months of the year. My take is that the change to rotten ice is the last penultimate state before bluewater [There are very deep stacks of wind-driven slabs now, yet, it's not multi-year ice in properties, not a replacement that way & the process making it not the same].

Albedo-loss is today= 20-years of CO2 forcing = 0.21-watts/m² ... at the FEEM talk last spring was stated that albedo-loss is the greatest source of warming in the Arctic by far, it's a specific-heat water vs reflected LWIR difference so a huge input.

The implications of not knowing this are big-deals in trying to use emissions to control global-warming, doesn't look good, far better to preserve sea-ice or bust.

Afaik albedo-loss heat-gain is not in models as a dynamic property if at all.

We have such good info already to not use it dynamically to me as a software architect is like unreal archaic thinking before API's.

The consequential condition is when large areas turn to rotten ice, not how much area is left, this can be done from satellite with recent voyages ground-proofing the satellite interpretation & last fall's voyage by APL, that involved a lot of institutions processing aspects now.

My vote really is for neither and use the data as outlined, neither are recognizing a pivotal new form of sea-ice and the relationship to albedo-loss to runaway heating of the Arctic to show the seriousness of losing the ice to total bluewater input in one season vs now.

We need to vizualize these relationships tied to what ice is there, to an old local there for the big melt of 2007 jellyfish thrive in the exposed sea, not more fish, the biological changes tied as well, eh?
-tom

Hans

  • New ice
  • Posts: 24
    • View Profile
  • Liked: 1
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #27 on: August 29, 2016, 09:43:22 PM »
IPCC is about Climate, and climate is not weather. In that view, 5 years is a short period, where 30 year averages are more common in climate definitions.
I fully support this definition. Anybody is free to set his own definition of ice free. It is not about an incidental summer, but about a general trend.
Remind that also 1 million km2 is just a number. Why not 1.1 or 0.4?
IPCC is well aware that there will be no return to the good old days. That is not the reason to wait 5 years. No definition of IPCC wil have impact on the real situation. lt is just wording. The main goal is to compare scenario calculations. Not to close down all coal fired power stations the day we dip below the "target".But if you want to compare different model forecasts from different research groups, it's nice to have a common agreement what you are comparing.

For me, the day someone is able to sail to the NP, without help from ice breakers will be the day. I guess that will have far more impact on the general public than any definition with "only 1 million left".

Iceismylife

  • Frazil ice
  • Posts: 281
    • View Profile
  • Liked: 2
  • Likes Given: 1
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #28 on: August 30, 2016, 05:44:24 PM »
...

Afaik albedo-loss heat-gain is not in models as a dynamic property if at all.

...
Over estimating CO2, underestimating albedo.

TerryM

  • Young ice
  • Posts: 4989
    • View Profile
  • Liked: 303
  • Likes Given: 5
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #29 on: August 30, 2016, 09:20:11 PM »
tim


Changes in albedo over time seems so important and so basic that I'd assumed every model would include it.


Are you sure that few or none do?


Terry

Rob Dekker

  • Nilas ice
  • Posts: 2287
    • View Profile
  • Liked: 95
  • Likes Given: 111
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #30 on: September 10, 2016, 07:39:29 AM »
On a separate thread, starting about here :
http://forum.arctic-sea-ice.net/index.php/topic,1457.msg89167.html#msg89167

we discussed how this new IPCC definition of "nearly ice-free for 5 consecutive years" came about.

It is present in the Summary for Policy makers, which is arguably the most important report that the IPCC produces :
http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_SPM_FINAL.pdf

In this report, there are 3 places that refer to the definition of an "ice-free" Arctic, with the clearest definition in a footnote on page 25 :
Quote
Conditions in the Arctic Ocean are referred to as nearly ice-free when the sea ice extent is less than 10^6 km2 for at least five consecutive years.

Now the interesting thing is that (as S.Pansa notes in the thread above) this definition was different in the Draft version (from June 7, 2013) :
https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/drafts/WG1AR5-SPM_FD_Final.pdf

Here the same footnote reads :
Quote
Conditions in the Arctic Ocean are referred to as ice-free when the sea ice extent is less than 10^6 km^2.

Now, since the final definition occurs at least 5 years after the draft definition, and there does not seem to be any reason to change the definition (looking at the final comments by all countries)
https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/drafts/WGIAR5_FGD_FinalDraftSPMComments.pdf
the question is, who changed the definition after the 'draft' version, when and why ?

After all, adding "for at least five consecutive years" to the definition buys you at least 5 years, which is about $ 20 trillion in fossil fuel revenue.
« Last Edit: September 10, 2016, 08:03:09 AM by Rob Dekker »
This is our planet. This is our time.
Let's not waste either.

P-maker

  • Frazil ice
  • Posts: 232
    • View Profile
  • Liked: 13
  • Likes Given: 0
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #31 on: September 10, 2016, 11:32:39 AM »
Rob

Sorry to have been neglecting your references to the difference between the AR5 WG I Draft SPM and the final version of that document.

Generally, footnotes are also agreed in plenary, so I assume the whole lot has seen the wording on the screen and approved it.

However, if you take a closer look at the comment made by the US (SPM-1678 in this document: https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/drafts/WGIAR5_FGD_FinalDraftSPMComments.pdf ), you will see this can of worms being opened up:

Quote
In Figure 2B, What is the source of sea ice going back to 1900?. Satellites only go to 1979, in the SPM Technical summary Figure TS12 sea ice record only plotted back to about 1960. The reliability of the pre-1979 instrumental record of sea ice could easily be drawn into question. Conversely there is little discussion or paleo-sea ice reconstructions which are extremely important as they show large variability including summer-sea ice free conditions in the Arctic at several times. Please crosscheck all sea ice sections across AR5. [Government of United States of America]
From these questions were made by the US, the scientists in consultation with the secretariat would have to “crosscheck” everything related to sea ice in AR5 and bring the results to the subsequent plenary. Consequently, a major change occurred in the footnote, and please note that the diagram (Fig 2B) was based mainly on observations from Jul-Aug-Sep, whereas the new sea ice diagram, which appeared both as Fig SPM.7 b - and in the SyR (Figure 2.1 c) a couple of years later - was for September only and mainly based on modelling results. Somewhere along the line, someone had the chance to tweak the definition of nearly sea ice free and apparently got away with it (until now).


Rob Dekker

  • Nilas ice
  • Posts: 2287
    • View Profile
  • Liked: 95
  • Likes Given: 111
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #32 on: September 11, 2016, 07:35:38 AM »
Thanks P-maker, for shining some light on the process.
Yet, the obscurity by which the "for five consecutive years" addition came about warrants further investigation.
Quote
Generally, footnotes are also agreed in plenary, so I assume the whole lot has seen the wording on the screen and approved it.
The addition also shows up in the caption of figure SPM.7.
That is already two places in the SPM alone.
So how, when and where did this happen and by whom ?

Just for clarity, we are talking here about the 36th session of the IPCC where the modifications proposed by WG1 (after the comments referenced above were incorporated) to the "final draft" of the Summary for Policy Makers were approved by all the countries involved.

This was the September 23-26, 2013, session in Stockholm, Sweden.
Here are the reports from that session :
http://www.ipcc.ch/scripts/_session_template.php?page=_36ipcc.htm

One interesting report there is listing the difference between the final draft (from June 7, 2013) and the SPM as approved during the September 23-26 session :
http://www.ipcc.ch/meetings/session36/p36_doc4_changes_underlying_assessment.pdf

And you can go through the whole list, but the addition of "for five consecutive years" to the "nearly ice free" definition is NOT THERE !

So I am not sure now if the addition "for five consecutive years" was visible during the plenary in Stockholm....

It actually looks like something happened under the table here...

All we know is that it IS NOT present in the June 7 'final draft SPM' as prepared by WG1
https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/drafts/WG1AR5-SPM_FD_Final.pdf
and it IS present in the 'approved SPM' after the September 23-26 session :
http://www.ipcc.ch/meetings/session36/p36_doc3_approved_spm.pdf

It remains a mystery WHO changed the definition, WHEN exactly, and WHY...

What we know for sure that with that new definition, any IPCC-definition-compliant "ice free" Arctic is postponed by at least 5 years (and probably much longer).

Just like that.
« Last Edit: September 11, 2016, 09:46:24 AM by Rob Dekker »
This is our planet. This is our time.
Let's not waste either.

crandles

  • Nilas ice
  • Posts: 2463
    • View Profile
  • Liked: 73
  • Likes Given: 44
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #33 on: September 19, 2016, 09:28:27 PM »
William Connolleys views:

First reply was
Quote
To which I’d say 1m km^2 is clearly arbitrary, but also (a) easy to compute and (b) a long way away; so its arbitrariness isn’t currently a problem. As we get somewhat closer to it in a few decades people will probably re-think the criterion more carefully.

I explained a bit more why I didn't think this adequately addressed the question and got

[I agree that “5 consecutive” years is a bit odd and a 5-year-average would be more “normal”… but I can’t get very excited about it, because it really doesn’t seem to matter. Unless someone is interested in “exactly when is this likely to occur under scenario X” which is probably not a sensible question anyway, as it is so far off and not really interesting that there’s no point looking at it in current models, unless you’re whoring after a cheap paper -W]

http://scienceblogs.com/stoat/2016/09/17/sea-ice-dull-as-expected/#comment-56864

seems a bit too dismissive to me.

oren

  • Young ice
  • Posts: 4302
    • View Profile
  • Liked: 762
  • Likes Given: 1230
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #34 on: September 19, 2016, 10:13:43 PM »
William Connolleys views:

First reply was
Quote
To which I’d say 1m km^2 is clearly arbitrary, but also (a) easy to compute and (b) a long way away; so its arbitrariness isn’t currently a problem. As we get somewhat closer to it in a few decades people will probably re-think the criterion more carefully.

I explained a bit more why I didn't think this adequately addressed the question and got

[I agree that “5 consecutive” years is a bit odd and a 5-year-average would be more “normal”… but I can’t get very excited about it, because it really doesn’t seem to matter. Unless someone is interested in “exactly when is this likely to occur under scenario X” which is probably not a sensible question anyway, as it is so far off and not really interesting that there’s no point looking at it in current models, unless you’re whoring after a cheap paper -W]

http://scienceblogs.com/stoat/2016/09/17/sea-ice-dull-as-expected/#comment-56864

seems a bit too dismissive to me.
This guy is really detached from reality. It seems like he genuinely dismisses "ice free arctic" as something a couple of generations down the line. Scary.

crandles

  • Nilas ice
  • Posts: 2463
    • View Profile
  • Liked: 73
  • Likes Given: 44
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #35 on: September 19, 2016, 10:24:13 PM »

This guy is really detached from reality. It seems like he genuinely dismisses "ice free arctic" as something a couple of generations down the line. Scary.

Not a couple of generations. He has said there will still be sea ice in summer in 50 years time (or was it in 2050?)

I think he is nearer right than some around here.

If he is detached from reality you should want to bet against him, right? He has paid up when I have won so that shouldn't be an excuse not to.

However, you might want to know he is £300 to £100 up against me. Whether that will change your view of just who is detached from reality, I will wait and see but I won't hold my breath.

Neven

  • Administrator
  • First-year ice
  • *****
  • Posts: 7069
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 651
  • Likes Given: 432
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #36 on: September 19, 2016, 11:59:16 PM »
seems a bit too dismissive to me.

What did you expect of WC? He's always skeptical for the sake of being skeptical. It's the British way, I guess (James Annan is like that too).
Il faut comparer, comparer, comparer, et cultiver notre jardin

crandles

  • Nilas ice
  • Posts: 2463
    • View Profile
  • Liked: 73
  • Likes Given: 44
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #37 on: September 20, 2016, 01:07:49 AM »
seems a bit too dismissive to me.

What did you expect of WC? He's always skeptical for the sake of being skeptical. It's the British way, I guess (James Annan is like that too).

Well yes but should we value a skeptical view? Dismissing such views completely seems like saying I know I am right and seems the route to DK effects.

A-Team

  • Nilas ice
  • Posts: 2317
    • View Profile
  • Liked: 237
  • Likes Given: 14
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #38 on: September 20, 2016, 03:50:28 AM »
This issue is worth pursuing. As Oren says, there will be blow-back down the road at the time of the first essentially ice-free season which will be upon us shortly. (Indeed this year, no one had the slightest scientific basis to rule it out well into June as not-unusual weather could have done the trick.)

I've just been floored by the arrogance, ignorance, indifference and general stupidity of outside responses so far to what is a very serious query about proceedings of the IPCC -- proceedings which need to be fully transparent. Manipulation of the official record by one of the parties, if that's what occurred, is a very serious matter and needs to be fixed. Now.

Neven

  • Administrator
  • First-year ice
  • *****
  • Posts: 7069
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 651
  • Likes Given: 432
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #39 on: September 20, 2016, 06:59:55 AM »
Well yes but should we value a skeptical view? Dismissing such views completely seems like saying I know I am right and seems the route to DK effects.

I'm not saying it should be dismissed, I'm just saying that it was to be expected that WC's view is a 'bit too dismissive'.
Il faut comparer, comparer, comparer, et cultiver notre jardin

Rob Dekker

  • Nilas ice
  • Posts: 2287
    • View Profile
  • Liked: 95
  • Likes Given: 111
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #40 on: September 20, 2016, 07:04:50 AM »
What did you expect of WC? He's always skeptical for the sake of being skeptical. It's the British way, I guess (James Annan is like that too).

William Connelly is skeptical, but in a good way.
For example, I started a bet with him 5 years ago, about Arctic sea ice :
http://scienceblogs.com/stoat/2011/06/26/betting-on-sea-ice-10000/

At that time (2011) it looked like Arctic sea ice was in a free fall, both for extent and for volume.
http://www.greenpeace.org/argentina/Global/international/artwork/climate/2011/average%20sea%20ice%20extent%20july.png
http://neven1.typepad.com/.a/6a0133f03a1e37970b014e87616da4970d-pi

If you would not know better, extrapolation suggested that I had the better hand :
http://rankexploits.com/musings/2011/connelly-dekker-bet-actually-robs-got-a-very-good-chance-of-not-losing/

So you have to respect William Connelly.
I thought is was quite bold of him to engage under the terms of this bet.

And then 2012 came along, and that made him nervous.
But then there was 2013 and 2014, and I got nervous.

In the end, the "trend" line appears to be right in between our two positions, which kind of means we were both wrong in our mutual opinions....

I'd buy William a beer any time, and I respect his opinion.
This is our planet. This is our time.
Let's not waste either.

Rob Dekker

  • Nilas ice
  • Posts: 2287
    • View Profile
  • Liked: 95
  • Likes Given: 111
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #41 on: September 20, 2016, 08:05:08 AM »
crandles, Sorry, but I asked William the same question as you did. I wonder if he is/was involved with the IPCC meetings and procedures enough to give a skillful answer.
 
This is our planet. This is our time.
Let's not waste either.

crandles

  • Nilas ice
  • Posts: 2463
    • View Profile
  • Liked: 73
  • Likes Given: 44
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #42 on: September 20, 2016, 03:32:40 PM »
crandles, Sorry, but I asked William the same question as you did. I wonder if he is/was involved with the IPCC meetings and procedures enough to give a skillful answer.

No need to be sorry - more a case of I should be sorry I rushed the process and didn't convey the all the info needed until at least the third attempt. I think he has got the picture now. Doubt he was involved enough judging by his "no personal experience" recent comment.

Rob Dekker

  • Nilas ice
  • Posts: 2287
    • View Profile
  • Liked: 95
  • Likes Given: 111
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #43 on: September 21, 2016, 09:17:12 AM »
William posted a separate blog on the issue :
http://scienceblogs.com/stoat/2016/09/20/dark-deeds-of-definitions/

If there was any nefarious intent, then inquiring about this with the IPCC authors will not lead anywhere. And if this addition of "five consecutive years" was not nefarious, then we will fix it in the next IPCC (AR6) reports. Either way, I don't think it matters much what we do now.
 
In summary, I don't feel good about pursuing this issue any further.
Should I ?
« Last Edit: September 21, 2016, 10:02:35 AM by Rob Dekker »
This is our planet. This is our time.
Let's not waste either.

Neven

  • Administrator
  • First-year ice
  • *****
  • Posts: 7069
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 651
  • Likes Given: 432
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #44 on: September 21, 2016, 10:54:47 AM »
I think you've done all you could, Rob, and it's another argument that shows the IPCC to be a conservative/reticent organisation.
Il faut comparer, comparer, comparer, et cultiver notre jardin

oren

  • Young ice
  • Posts: 4302
    • View Profile
  • Liked: 762
  • Likes Given: 1230
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #45 on: September 21, 2016, 11:38:03 AM »
Good action Rob and Crandles. At least now it's out in the open and acknowledged.
I personally still find William's calm and assured remark that we are decades away from 1m km2, without acknowledging any possibility or risk to the contrary, to be detached from reality. Just my two cents.

Edit reason: A Richard is not a William! Thank you Rob.
« Last Edit: September 22, 2016, 04:49:30 PM by oren »

Rob Dekker

  • Nilas ice
  • Posts: 2287
    • View Profile
  • Liked: 95
  • Likes Given: 111
Re: IPCC AR5 Definition of "Nearly ice-free conditions"
« Reply #46 on: September 22, 2016, 07:46:32 AM »
Oren: I guess you mean William, not Richard.

Neven: Not sure if this (re-definition of "nearly ice free") has anything to do with the IPCC as an organization. This particular issue feels more the action of a single individual who found a minor crack in the IPCC procedures.

As P-maker stated elsewhere in this thread :
Quote
Somewhere along the line, someone had the chance to tweak the definition of nearly sea ice free and apparently got away with it (until now).
This is our planet. This is our time.
Let's not waste either.