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gregcharles

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Re: IJIS
« Reply #4450 on: June 29, 2017, 08:29:59 AM »
Just to be I'm understanding it, the theory is that Windsat data clumped losses onto certain days, but not that it showed greater overall losses than AMSR2 would have. Is that right?

Neven

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Re: IJIS
« Reply #4451 on: June 29, 2017, 09:56:20 AM »
Just to be I'm understanding it, the theory is that Windsat data clumped losses onto certain days, but not that it showed greater overall losses than AMSR2 would have. Is that right?

As far as I know, that's right.
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Jim Hunt

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Re: IJIS
« Reply #4452 on: June 29, 2017, 12:57:29 PM »
Just to be I'm understanding it, the theory is that Windsat data clumped losses onto certain days, but not that it showed greater overall losses than AMSR2 would have.

The relevant section of the JAXA/ADS web site reads:

Quote
In principle, SIC data could have errors of 10% at most, particularly for the area of thin sea ice seen around the edge of sea-ice cover and melted sea ice seen in summer. Also, SIC along coastal lines could also have errors due to sub-pixel contamination of land cover in an instantaneous field of view of PMR data.

In general, sea-ice extent is defined as a temporal average of several days (e.g., five days) in order to eliminate calculation errors due to a lack of data (e.g., for traditional microwave sensors such as SMMR and SSM/I). However, we adopt the average of latest two days (day:N & day:N-1) to achieve rapid data release. Only for the processing of WindSat data (Oct. 4, 2011 to the present(sic!)) the data of the day before yesterday (day:N-2) is also sometimes used to fill data gaps.

I know folks get excited about century breaks, but they can easily be an artifact of the noisy data. For a recent example of the potential problems see this from Wipneus:

http://forum.arctic-sea-ice.net/index.php/topic,382.msg117687.html#msg117687

For comparison purposes my hastily modified NSIDC daily extent spreadsheet reveals 21 CBs by June 27th 2012, one of which was in January. The NSIDC 5 day averaged metric was up to 15 CBs by the 27th.
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pauldry600

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Re: IJIS
« Reply #4453 on: June 30, 2017, 02:18:57 PM »
Down another 90k

We are 171k behind lowest year

Espen

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Re: IJIS
« Reply #4454 on: June 30, 2017, 03:20:33 PM »
IJIS:

9,112,470 km2(June 29, 2017)down 91,845 km2 and 3rd lowest measured for the date.
Have a ice day!

dmarcus

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Re: IJIS
« Reply #4455 on: June 30, 2017, 03:22:48 PM »
3rd lowest for this date. 6/29/17 value of 9112K is 78K above 2016, 171K above 2010. In the other direction, the 6/29/17 value is 42K below 2011, 51K below 2012, and 73K below 2014. So despite being 3rd lowest for the date, 6/29/2017 is closer to 6th than 2nd.

charles_oil

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Re: IJIS
« Reply #4456 on: June 30, 2017, 04:07:36 PM »

or just 2 days later than the lowest


pileus

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Re: IJIS
« Reply #4457 on: June 30, 2017, 04:29:29 PM »
The gist is that the latest daily measurement is about 10% below 2000s averages and 20% below 1980s averages.  Whether it is 100k on either side of the lowest or 6th lowest daily at figure at this point with 2.5 months left in the melting season is largely just a curious detail. 

It remains a shocking and significant decadal trend for a process that should play out over centuries or millennia.

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Re: IJIS
« Reply #4458 on: June 30, 2017, 06:10:31 PM »
3rd lowest for this date. 6/29/17 value of 9112K is 78K above 2016, 171K above 2010. In the other direction, the 6/29/17 value is 42K below 2011, 51K below 2012, and 73K below 2014. So despite being 3rd lowest for the date, 6/29/2017 is closer to 6th than 2nd.

instead of ranting again i simply ask you, means i ask a question and explain why i ask, so nothing personal, ok?

why? because if the information in such posts is reduced and translated into one short sentence they say that we are closer to recovery/positive side than to the worse which at least IMO is dead wrong.

we are looking into an abyss so to say since this is not a pure seasonal thread i think it's legit to say so, while in a seasonal thread it would not be legit because no-one knows when the overhanging rock we are standing on will break of or when mankind will jump.


what do you want to say with this, because the only thing i can imagine is that things are getting better or that they are not THAT bad but again many forget that 5% lower volume compared to 2% higher extent is a huge gap in ice to melt out, hence energy needed to melt what's there, on the negative side means, MUCH LESS ICE MASS than last year and any year before that

i simply can't get over this kind of posts which i personally think that they are either misleading for newcomers or being ignorant of certain factors like thickness, fragmentation and the likes. not saying which because i dunno and there are probably more possibilities than those two.

if you want you can PM me your intention, perhaps i'm the one to learn something and will shut up in the future once someone can give me a good explanation about what the meaning could be, other than simply posting numbers of course but i see not much benefit in reading every days dozens of posts with 3rd, 4th and so on lowest and the related speculations in the aftermath.

again, tell my your reason and i promise to learn if there is something to it.

if we are driving with a car into a turn either 10cm or 1m from the cliff/edge which is safer?

at first glance one meter seam to be safer but not if we are driving at 100mph into a 90 degree corner. if the turn is sharp it's safer to drive 20mbh 10cm from the cliff/edge.

this is just an example because IMO we are now a bit farther from the cliff/edge but way too fast and will shoot over eventually
« Last Edit: June 30, 2017, 06:22:09 PM by magnamentis »

gerontocrat

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Re: IJIS
« Reply #4459 on: June 30, 2017, 06:18:13 PM »
3rd lowest for this date. 6/29/17 value of 9112K is 78K above 2016, 171K above 2010. In the other direction, the 6/29/17 value is 42K below 2011, 51K below 2012, and 73K below 2014. So despite being 3rd lowest for the date, 6/29/2017 is closer to 6th than 2nd.

instead of ranting again i simply ask you, means i ask a question and explain why i ask, so nothing personal, ok?

what do you want to say with this, because the only thing i can imagine is that things are getting better or that they are not THAT bad but again many forget that 5% lower volume compared to 2% higher extent is a huge gap in ice to melt out, hence energy needed to melt what's there, on the negative side means, MUCH LESS ICE MASS than last year and any year before that

i simply can't get over this kind of posts which i personally think that they are either misleading for newcomers or being ignorant of certain factors like thickness, fragmentation and the likes. not saying which because i dunno and there are probably more possibilities than those two.

if you want you can PM me your intention, perhaps i'm the one to learn something and will shut up in the future once someone can give me a good explanation about what the meaning could be, other than simply posting numbers of course but i see not much benefit in reading every days dozens of posts with 3rd, 4th and so on lowest and the related speculations in the aftermath.

again, tell my your reason and i promise to learn if there is something to it.
This is the thread on which is posted the numeric data from JAXA. "It is what it is". Elsewhere are images and data from images and weather / SSTs , volume etc on what is now and may be in the near future. From that one might make interpretations on the future.
But data is just data. It does not express an opinion. It just is.
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Shared Humanity

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Re: IJIS
« Reply #4460 on: June 30, 2017, 07:19:58 PM »

This is the thread on which is posted the numeric data from JAXA. "It is what it is". Elsewhere are images and data from images and weather / SSTs , volume etc on what is now and may be in the near future. From that one might make interpretations on the future.
But data is just data. It does not express an opinion. It just is.

Thank you.

We are following extent here. As such, the discussion needs to center on, by golly, extent. No one, and I mean no one, should be chastised about any comment on the current extent numbers or trends or any other relevant comment about specific regions and the nature of that extent. I get tired of reading comments like this.

greatdying2

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Re: IJIS
« Reply #4461 on: July 01, 2017, 06:41:36 AM »
Why are people arguing about noise? The trend is obvious. Just look at the graph.
The Permian–Triassic extinction event, a.k.a. the Great Dying, occurred about 250 million years ago and is the most severe known extinction event. Up to 96% of all marine species and 70% of terrestrial vertebrate species became extinct; it is also the only known mass extinction of insects.

Juan C. García

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Re: IJIS
« Reply #4462 on: July 01, 2017, 07:28:43 AM »
We really need several Century drops....  Got to get to Zero Ice..  We need to be happy we are right!

To be at the same level than 2012 on June 30th (9,039,911 km2), we need an average daily drop of 74,289 km2.

June 30th:
2012: 9.04 million km2
2017: 9.03 million km2

How it happened? Without melt ponds?
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.

pauldry600

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Re: IJIS
« Reply #4463 on: July 01, 2017, 08:11:20 AM »
145k behind the record

It is happening coz theres not much good ice

About 70 to 75 days left

2016 had a huge lead over 2017 but its only about 50k ahead now

No doubt even if theres a record the deniers will still be out in force. "Freak weather caused that over 1 year"

Tigertown

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Re: IJIS
« Reply #4464 on: July 01, 2017, 08:33:46 AM »
Quote
How it happened? Without melt ponds?

Warm air and rain, which melted the snow, lowered albedo, and made instant melt ponds. A little help from wave action, too. Not saying there were no other factors, but I believe these were main contributors.

Quote
It is happening coz theres not much good ice
That too.
"....and the appointed time came for God to bring to ruin those ruining the earth." Revelation 11:18.

oren

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Re: IJIS
« Reply #4465 on: July 01, 2017, 08:45:38 AM »
2012's record was set in late July and August, in the CAB. Main losses now come from the far periphery. The extent numbers at this stage don't contain enough information to assess probabilty of a record.

Lord M Vader

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Re: IJIS
« Reply #4466 on: July 01, 2017, 09:27:57 AM »
I think we can be fairly sure that the minimum will be lower than 2013 which ended up at 4,80 Mn km2. The next 2 weeks will be crucial in determining the prospect of a new record. I think the odds are pretty low, say 5% that we'll see a new record minimum. And that's not the real point, of more concern should be how long the open areas are. Chukchi and ESS as well as Beaufort will have another month to absorb the heat from the sun and warm the waters. And this will have effects later this fall and winter.

And I still believe we'll see a fairly big El Niño next year which will ramp up the temps in the Arctic even more during winter and fall and yield more early openings and so on.

Espen

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Re: IJIS
« Reply #4467 on: July 01, 2017, 10:24:04 AM »
IJIS:

9,030,644 km2(June 30, 2017)down 81,826 km2 and 3rd lowest measured for the date.
Have a ice day!

gerontocrat

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Re: IJIS
« Reply #4468 on: July 01, 2017, 04:15:51 PM »
Herewith some analysis of Jaxa sea ice extent numbers. The projections are not meant to be forecasts in any sense of the word. Rather they are attempts to test what melting is required from now to minimum to achieve certain results.

 As at June 30              Melt        As % of      Resulting 
                             Required     07/16 av.   Minimum
 For 2016 Result     5,013,380    101.1%    4,017,264
 For 2012 Result     5,853,189    118.0%    3,177,455
 For 2007 Result     4,964,905    100.1%    4,065,739
 Av 2007-16 melt        4,960,046    100.0%    4,070,598
 For 1 million km2     8,030,644    161.9%    1,000,000

It is obvious that a 2nd lowest miminum only requires remaining melt to be a modest fraction greater than the average remaining melt in the last 10 years.

For the magic 1 million km2 minimum, melt from now to minimum has to be 62% above the 2007-2016 average. This seems unlikely, given variations in previous years.

For a record low (below 2012), remaining melt has to be at least 18% above the previous 10 year average. This has only happened once in the satellite record - in 2012. My memory of 2012 was that it was the late season melt that made 2012 such a record record low. So I looked at the Jaxa record. In 2012, melt from Aug 1st to minimum was 35 % greater than the 2007-16 Average. In 2008 it was + 15%. No other year comes close.

 Melt Aug1 to min    Km2         cf with 07-16
1980's Average       1,588,705    -26%
1990's Average       1,502,583    -30%
2000's Average       1,728,320    -20%
2002    No data    
2003                       1,658,226    -23%
2004                       2,181,360       2%
2005                       1,721,140    -20%
2006                       1,345,561    -37%
2007                       2,116,693      -1%
2008                       2,466,075      15%
2009                       1,717,881     -20%
2010                       2,036,131       -5%
2011                       2,039,229       -5%
2012                       2,904,945       35%
2013                       1,833,934      -15%
2014                       1,848,264      -14%
2015                       2,211,140         3%
2016                       2,304,571         7%
Av. 2007-2016       2,147,886         0%


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Shared Humanity

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Re: IJIS
« Reply #4469 on: July 01, 2017, 07:45:12 PM »
Thank you for this.

Given the weak freeze this past winter and the resulting thin ice, I can't imagine that the remainder of the melt season will not be more than the average over the past 10 years. I also would be surprised if it melts like 2012. So it looks like 2nd place is most likely.

Lord M Vader

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Re: IJIS
« Reply #4470 on: July 01, 2017, 08:53:28 PM »
A big contributor to the amazing melt in early August 2012 was the GAC. Surely, there would have been a record but the question is how big the melt rate in August 2012 would have been without the GAC.

gerontocrat

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Re: IJIS
« Reply #4471 on: July 01, 2017, 09:41:32 PM »
A big contributor to the amazing melt in early August 2012 was the GAC. Surely, there would have been a record but the question is how big the melt rate in August 2012 would have been without the GAC.
Brain-fade. GAC IS ?
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crandles

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Re: IJIS
« Reply #4472 on: July 01, 2017, 09:45:44 PM »
Great Arctic Cyclone

Tor Bejnar

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Re: IJIS
« Reply #4473 on: July 01, 2017, 11:21:15 PM »
ASIG, BOE, CAPIE:  when you don't know what an abbreviation means, just go to the Arctic Sea Ice menu's     
Glossary ... for newbies and others (pegged near the top).  If it's not there, please ask (probably on that thread).  Neven is surprised, occasionally, to find a commonly used abbreviation (that is, used on this forum) missing, and adds it to that list. (Some abbreviations found on these threads are common texting abbreviations.)

If one of the listed ASIF abbreviations hasn't been used in a while, it may be kind to newbees (and us with warn-out brains) to re-introduce the abbreviation with the term.
Arctic ice is healthy for children and other living things.

Darvince

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Re: IJIS
« Reply #4474 on: July 01, 2017, 11:47:28 PM »
http://onlinelibrary.wiley.com/doi/10.1002/grl.50190/abstract

The 2012 minimum still would've been quite substantial without the 2012 August GAC, but there would have likely been a hint of a Wrangel arm like the 2016 one, but much smaller.

Bill Fothergill

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Re: IJIS
« Reply #4475 on: July 02, 2017, 08:55:38 AM »
Ho hum, looks like there will be a little more twitching...


gerontocrat

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Re: IJIS
« Reply #4476 on: July 02, 2017, 10:57:07 AM »
Great Arctic Cyclone
Now I remember, watching in near disbelief the cyclone and the melt. Like everyone else thinking "Is this the one ?",  and then along came 2013 and the answer was "NO".
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Bill Fothergill

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Re: IJIS
« Reply #4477 on: July 02, 2017, 04:28:39 PM »
This is the thread on which is posted the numeric data from JAXA. "It is what it is". Elsewhere are images and data from images and weather / SSTs , volume etc on what is now and may be in the near future. From that one might make interpretations on the future.
But data is just data. It does not express an opinion. It just is.

By and large, I completely agree with that sentiment. However, there are instances when the data can either be in error, or can be subject to misuse/misinterpretation.

On 2017 Melting Season thread, there was a recent comment which indirectly alluded to this.
This means one has to trust intuition of people who work in the field, personally, - more than usual.
...
 and sadly we can never know for sure what kind of errors (or even worse - bias) data processing made by other people may have.

Whilst we are waiting for the IJIS/JAXA/ADS site to complete its maintenance run, it may be educational to look at a form of data error which appears on ADS Vishop Version 2.

On the right hand side of their Extent Graphs page, there is a Graph Option selector. One of the options displays a simple line chart showing the progression of the annual average SIE. (The minimum and maximum values for each year can also be displayed.)

The first pair of charts below show the annual average SIE for both the Arctic and the Antarctic as they appear on ADS Vishop Ver 2. Something that should literally jump off the screen - at least for anyone familiar with the data - is the anomalous spike seemingly occurring in 1987 for both hemispheres. (A downward spike for the Arctic, and an upward spike for the Antarctic.)

However, the second pair of charts comparing the ADS and NSIDC annual average SIE makes this even clearer. Although the absolute values from ADS tend to be several hundred thousand sq kms lower than those from the NSIDC, the inter-annual variations exhibited by both usually track each other with a high level of agreement - except for 1987. (And, to a much lesser extent - no pun intended - in the 1980 Antarctic data.)

The "discrepancy" in 1987 is, of course, partially explained by the switch from alternate day to daily recording during July of that year. This change to recording frequency immediately introduces a weighting bias in favour of data gathered in the second half of the year. As the second half of each year encompasses the Arctic minimum and the Antarctic maximum, the averages thus calculated become skewed. In each case, the situation is exacerbated by further spurious data drops in January, April and December.

In the case of the 1980 data example, there are 4 data drops (each covering 3 or 4 measurement periods) spread from January through to April.

Using a simple linear interpolation, a proxy was created for the the missing data and for the incorrectly weighted data and more realistic annual averages were created for 1987 (both hemispheres) and for the Antarctic only in 1980. (NB A similar correction could have been applied in the Arctic, and this would have resulted in a better tracking there as well. However, I only carried out this correction for the Antarctic as the unadjusted averages actually went in different directions.)

The third pair of charts show how the ADS and NSIDC annual average SIE numbers would compare following such a data-infill exercise. The infill causes the Arctic annual average figure to rise by around 1 million sq kms, whilst the Antarctic equivalent falls by nearly 2 million sq kms.


The moral, if there is one, is that we can check up on certain aspects of the data ourselves. It just takes a bit of understanding, and a little bit of effort.

gerontocrat

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Re: IJIS
« Reply #4478 on: July 02, 2017, 04:38:02 PM »
I agree - data must be tested. "Question all assumptions " is always a good motto. However, the response was to a post that suggested that the data was bent through malicious intent. I felt that would not do.
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Shared Humanity

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Re: IJIS
« Reply #4479 on: July 02, 2017, 05:29:45 PM »
I agree - data must be tested. "Question all assumptions " is always a good motto. However, the response was to a post that suggested that the data was bent through malicious intent. I felt that would not do.

If the data is being manipulated in order to convince us there is no problem with melting ice, they need to do a better job.    ::) ;) 8)

Bill Fothergill

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Re: IJIS
« Reply #4480 on: July 02, 2017, 05:53:56 PM »
I agree - data must be tested. "Question all assumptions " is always a good motto. However, the response was to a post that suggested that the data was bent through malicious intent. I felt that would not do.

Yep. I'm going to do a further response to what you and Shared Humanity were saying.

However, as I'm being dragged out for some beer to (belatedly) celebrate having dodged the coffin for yet another orbit of Sol, that must, perforce, wait until tomorrow.

gerontocrat

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Re: IJIS
« Reply #4481 on: July 02, 2017, 07:25:23 PM »
I agree - data must be tested. "Question all assumptions " is always a good motto. However, the response was to a post that suggested that the data was bent through malicious intent. I felt that would not do.

Yep. I'm going to do a further response to what you and Shared Humanity were saying.

However, as I'm being dragged out for some beer to (belatedly) celebrate having dodged the coffin for yet another orbit of Sol, that must, perforce, wait until tomorrow.
The advantage of age is to say "you can wait until tomorrow". I am off to a quiz with some other ancients. The objective is beer and sarcasm to the young.
Happy Birthday.
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Deeenngee

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Re: IJIS
« Reply #4482 on: July 02, 2017, 09:34:47 PM »
A monthly update of the graphs best described as the IJIS graphs that I update on a monthly basis.
First, 2017 vs the range & decadal averages.
Second, cumulative days in the bottom 3 for 1990-2017.
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Deeenngee

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Re: IJIS
« Reply #4483 on: July 02, 2017, 09:52:30 PM »
Thirdly, the psychedelic toothpaste comparison of 2017 and previous rolling 10 year averages.

(PS OT, what was your quiz team name, Gerontocrat?)
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Feeltheburn

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Re: IJIS
« Reply #4484 on: July 03, 2017, 02:07:58 AM »
Herewith some analysis of Jaxa sea ice extent numbers. The projections are not meant to be forecasts in any sense of the word. Rather they are attempts to test what melting is required from now to minimum to achieve certain results.

 As at June 30              Melt        As % of      Resulting 
                             Required     07/16 av.   Minimum
 For 2016 Result     5,013,380    101.1%    4,017,264
 For 2012 Result     5,853,189    118.0%    3,177,455
 For 2007 Result     4,964,905    100.1%    4,065,739
 Av 2007-16 melt        4,960,046    100.0%    4,070,598
 For 1 million km2     8,030,644    161.9%    1,000,000

It is obvious that a 2nd lowest miminum only requires remaining melt to be a modest fraction greater than the average remaining melt in the last 10 years.


The biggest variable that will determine the SIE low this year will likely be the wind. If there is another GAC, ice could be as low as 2012. If no wind to speak of, then it will likely end higher than 2007 and 2017, both of which experienced late season wind events that caused SIE to drop faster than it would have otherwise.
« Last Edit: July 03, 2017, 04:18:30 PM by Feeltheburn »
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DavidR

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Re: IJIS
« Reply #4485 on: July 03, 2017, 07:46:16 AM »
Two century breaks put 2017 within 90K of lowest. 
Toto, I've a feeling we're not in Kansas anymore

Espen

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Re: IJIS
« Reply #4486 on: July 03, 2017, 05:31:52 PM »
IJIS:

8,821,604 km2(July 2, 2017)and 3rd lowest measured for the date.
Have a ice day!

oren

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Re: IJIS
« Reply #4487 on: July 03, 2017, 05:40:46 PM »
209k in two days, humming along.

pauldry600

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Re: IJIS
« Reply #4488 on: July 04, 2017, 12:53:29 PM »
down another 80K

Gap to lowest still narrowing but 2016 will take a leap ahead in the next few days

binntho

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Re: IJIS
« Reply #4489 on: July 04, 2017, 12:58:23 PM »
down another 80K

Gap to lowest still narrowing but 2016 will take a leap ahead in the next few days
You mean 2017?
because a thing is eloquently expressed it should not be taken to be as necessarily true
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pauldry600

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Re: IJIS
« Reply #4490 on: July 04, 2017, 03:50:01 PM »
No 2016 dropped a huge amount on these days last year

Espen

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Re: IJIS
« Reply #4491 on: July 04, 2017, 05:55:32 PM »
IJIS:

8,741,930 km2(July 3, 2017)down 79,674 km2 and 3rd lowest measured for the date.
Have a ice day!

southseas

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Re: IJIS
« Reply #4492 on: July 05, 2017, 05:28:35 AM »


I'll place money on the certainty that 2017 will move below 2016 within the next eight weeks, and stay there for some time.

Ah well you would have lost ... just! ;)

Not trying to be smart, but it does rather illustrate the folly of betting on the noise rather than the trend (sadly a much surer bet)

Sourabh

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Re: IJIS
« Reply #4493 on: July 05, 2017, 06:10:35 AM »


I'll place money on the certainty that 2017 will move below 2016 within the next eight weeks, and stay there for some time.

Ah well you would have lost ... just! ;)

Not trying to be smart, but it does rather illustrate the folly of betting on the noise rather than the trend (sadly a much surer bet)

Eight weeks will complete next week. So, there are still six days left.  ;)

gregcharles

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Re: IJIS
« Reply #4494 on: July 05, 2017, 06:56:47 AM »


I'll place money on the certainty that 2017 will move below 2016 within the next eight weeks, and stay there for some time.

Ah well you would have lost ... just! ;)

Not trying to be smart, but it does rather illustrate the folly of betting on the noise rather than the trend (sadly a much surer bet)

Eight weeks will complete next week. So, there are still six days left.  ;)

Want to bet on that?  ;)

Sourabh

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Re: IJIS
« Reply #4495 on: July 05, 2017, 07:22:48 AM »

Want to bet on that?  ;)

In order to catch up with 2016, approximately 470,000 km2 of SIE must be lost by 9th July, which translates into roughly 95,000 km2 per day.

So, bet is on. That is all we can do now. ;D

southseas

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Re: IJIS
« Reply #4496 on: July 05, 2017, 12:04:24 PM »
Perhaps you should check your counting before you take Greg's bet ;)

Bill Fothergill

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Re: IJIS
« Reply #4497 on: July 05, 2017, 01:05:44 PM »
It's a shame to see someone throw their money away on a zero-possibility bet.     ;)

Here's the arithmetic to which Greg and southseas were referring...

8th May 2017 equates to Day 128

add 8 weeks (56 days) gives Day 184, which is July 3rd

Jim Pettit

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Re: IJIS
« Reply #4498 on: July 05, 2017, 01:15:30 PM »


I'll place money on the certainty that 2017 will move below 2016 within the next eight weeks, and stay there for some time.

Ah well you would have lost ... just! ;)

Not trying to be smart, but it does rather illustrate the folly of betting on the noise rather than the trend (sadly a much surer bet)

In my defense, extent is now just 9k km2 below 2016's same-day number. So it almost made it. And I was talking about two months generally, not eight weeks specifically, though I said eight weeks so you got me there. ;-)
« Last Edit: July 05, 2017, 01:33:30 PM by Jim Pettit »

dnem

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Re: IJIS
« Reply #4499 on: July 05, 2017, 01:27:07 PM »
Sorry to be a grump, but this whole horse race strikes me as a bit silly.  Arctic SIE is bumping bottom along with several other recent years within the error of the measurement system, no?