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oren

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Re: 2018 sea ice area and extent data
« Reply #1100 on: July 19, 2018, 05:20:48 PM »
Thank you A-Team. I knew that but was missing a definitive visual proof.

Steven

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Re: 2018 sea ice area and extent data
« Reply #1101 on: July 19, 2018, 08:34:08 PM »
Ho hum.

NSIDC has put in the data that automatically sorted out my data. Pity that all the posts since 9th July were pretty much a waste of time.


I'm not sure what you are talking about.  The data on the NSIDC website are still consistent with the data I had saved on my computer last weekend.  There have been no revisions whatsoever. 

I guess there was just a temporary problem with the data file you are using: the file had several incorrect values on 17 July.  The file for 18 July is consistent with the file for 16 July (and previous days); only the file for 17 July was wrong.
« Last Edit: July 19, 2018, 08:39:12 PM by Steven »

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1102 on: July 19, 2018, 09:31:44 PM »
Ho hum.

NSIDC has put in the data that automatically sorted out my data. Pity that all the posts since 9th July were pretty much a waste of time.


I'm not sure what you are talking about.  The data on the NSIDC website are still consistent with the data I had saved on my computer last weekend.  There have been no revisions whatsoever. 

I guess there was just a temporary problem with the data file you are using: the file had several incorrect values on 17 July.  The file for 18 July is consistent with the file for 16 July (and previous days); only the file for 17 July was wrong.

At around 2 pm British Summer Time on the 17th of July, I uploaded NSIDC's daily extent and regional area and extent spreadsheets, which then automatically updated my spreadsheets. I then as usual posted the area tables, missing days, warts, and all. (e.g. see attached screenshot)

https://forum.arctic-sea-ice.net/index.php/topic,2223.msg163587.html#msg163587

The following day the gaps were filled.
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Re: 2018 sea ice area and extent data
« Reply #1103 on: July 19, 2018, 10:12:51 PM »
Sure.  But you were saying that:

Pity that all the posts since 9th July were pretty much a waste of time

which isn't the case.  The tables you posted upthread on 18 July are consistent with the ones you posted on 16 July and previous days.  Apart from the erroneous data file on 17 July, everything seems fine.

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1104 on: July 19, 2018, 11:06:12 PM »
Sure.  But you were saying that:

Pity that all the posts since 9th July were pretty much a waste of time

which isn't the case.  The tables you posted upthread on 18 July are consistent with the ones you posted on 16 July and previous days.  Apart from the erroneous data file on 17 July, everything seems fine.
I agree the data now looks OK. But my post re the 16th July said daily loss 116 K, now that has been corrected to 79k. So the analysis of daily change sea by sea was junk. I maintain that once the problems e.g. with Hudson Bay extent and area, were evident, it would have been better for me to leave off posting until the sorting out was done.

But of more moment is what on earth is the remainder of this season going to do, or not do?
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Juan C. García

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Re: 2018 sea ice area and extent data
« Reply #1105 on: July 20, 2018, 01:25:19 AM »
Ho hum.

NSIDC has put in the data that automatically sorted out my data. Pity that all the posts since 9th July were pretty much a waste of time.


I'm not sure what you are talking about.  The data on the NSIDC website are still consistent with the data I had saved on my computer last weekend.  There have been no revisions whatsoever. 

I guess there was just a temporary problem with the data file you are using: the file had several incorrect values on 17 July.  The file for 18 July is consistent with the file for 16 July (and previous days); only the file for 17 July was wrong.


Maybe it is related to the following e-mail from NSIDC (Date July 17th, 2018):


Dear Colleague,

NOAA@NSIDC is pleased to announce that the Sea Ice Index has been updated from near-real-time data to final data for the time period 01 January 2016 through 31 December 2017. Initially, when the Sea Ice Index is first processed, it uses a near-real-time (NRT) sea ice concentration product as an input. This NRT product can contain missing data and has less stringent quality control applied than the final sea ice concentration input product provided by NASA Goddard. However, the final input product often lags behind by approximately one year. Using the NRT product allows the Sea Ice Index to provide sea ice extent and concentration data for the previous day. When the final NASA Goddard sea ice concentration product becomes available, NOAA@NSIDC reprocesses data for that time period so that the higher quality data are used for the Sea Ice Index computations. To access the newest data, please visit the Sea Ice Index landing page: https://nsidc.org/data/g02135

Data Acknowledgements
Authors: Fetterer, F., K. Knowles, W. Meier, M. Savoie, and A. K. Windnagel
DOI: https://doi.org/10.7265/N5K072F8
Data Center: http://nsidc.org/noaa

If you have any questions, please contact the User Services Office by addressing your messages to nisdc@nsidc.org.

Best regards,
NSIDC User Services
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

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Re: 2018 sea ice area and extent data
« Reply #1106 on: July 20, 2018, 06:07:54 AM »
[ADS-NIPR-JAXA] ASI Extent.

July 19th, 2018: 7,851,927 km2, a drop of -95,373 km2.
The average drop on the last seven days starts to be above average: 93.9K km2.
2018 is the tenth lowest on record.
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.

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1107 on: July 20, 2018, 08:44:42 AM »
JAXA ARCTIC EXTENT 7,851,927 km2(July 19, 2018)

Just to add to Juan's post:-
- Extent is 457 k (5.8%) above the 2010's average extent on this date,
- Extent loss to date is 790k km2 (11.6%) below the 2008-2017 average, with 69% of the average melting season done.

Resulting minimum from average remaining melt = 4.72 million km2, (excluding 2012 from the average 4.82 million km2). Range of results from last ten years remaining melt is 3.81 to 5.25 million km2.

It is that 2017 feeling  - extent losses even when above average never enough to catch up on the slow melt to date. There is, on average, less than one third of further extent loss to go. In one weeks time daily extent loss, on average, will be already in significant decline. A September minimum of 4.75 to 5.25 million km2 still looks the most likely outcome.
« Last Edit: July 20, 2018, 09:02:50 AM by gerontocrat »
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1108 on: July 20, 2018, 02:32:34 PM »
NSIDC Total Area as at 19 July (5 day trailing average =  5,628,747 km2
This has now increased to 221 k above the 2010-2017 average


Total Area loss 64 K, Central Seas 59k, Periphery loss 3 k, Other Seas loss 3 k  
Analysis of individual seas.

Pacific Side
- The Okhotsk Sea area is 4 k,
- The Bering Sea area is 2 k,
- Chukchi Sea loss 6 k,
- Beaufort Sea loss 10 k,
Atlantic Side
- Baffin Sea loss 1 k,
- Greenland Sea loss 1 k,
- Barents Sea loss 1 k -  area is 4 k, i.e. melting season over.
- The Kara Sea area loss 14 k.
- The Laptev Sea area loss 4 k.
CAB
- The Central Arctic Sea loss 3 k,
- The Canadian Archipelago loss  8 k,
- East Siberian Sea loss 13 k .
Other seas
- St Lawrence area at 1 k,
- Hudson Bay area loss 3 k.

Area loss 30+k below average on the day, and a similar story over the last five days.
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Steven

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Re: 2018 sea ice area and extent data
« Reply #1109 on: July 20, 2018, 07:57:37 PM »
The tables you posted upthread on 18 July are consistent with the ones you posted on 16 July and previous days.  Apart from the erroneous data file on 17 July, everything seems fine.
I agree the data now looks OK. But my post re the 16th July said daily loss 116 K, now that has been corrected to 79k. So the analysis of daily change sea by sea was junk. I maintain that once the problems e.g. with Hudson Bay extent and area, were evident, it would have been better for me to leave off posting until the sorting out was done.

That 116k number only appears in the erroneous data file that was posted on 17 July.  I already said twice that that file should be ignored, but you're obviously not paying attention.  The tables you posted on 18 July are consistent with the ones you posted on 16 July (or any day apart from 17 July).  There have been no revisions whatsoever.


Neven

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Re: 2018 sea ice area and extent data
« Reply #1110 on: July 20, 2018, 10:24:10 PM »
Compactness going down again, middle of the pack:
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Juan C. García

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Re: 2018 sea ice area and extent data
« Reply #1111 on: July 21, 2018, 05:57:41 AM »
[ADS-NIPR-JAXA] ASI Extent.

July 20th, 2018: 7,717,932 km2, a century drop of -133,995 km2.
2018 is the tenth lowest on record.
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.

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1112 on: July 21, 2018, 10:27:12 AM »
JAXA ARCTIC EXTENT 7,717,932 km2(July 20, 2018)

Just to add to Juan's post:-
- Extent is down a bit to 406 k (5.3%) above the 2010's average extent on this date,
- Extent loss to date is 750k km2 (10.8%) below the 2008-2017 average, with 69.5% of the average melting season done.

Resulting minimum from average remaining melt = 4.68 million km2, (excluding 2012 from the average 4.78 million km2). Range of results from last ten years remaining melt is 3.74 to 5.17 million km2.

3 days losses above average in a row and the last an impressive 133k, but that 2017 feeling remains - extent losses even when above average never enough to catch up on the slow melt to date. There is, on average, less than one third of further extent loss to go. In one weeks time daily extent loss, on average, will be already in significant decline. A September minimum in the range of 4.75 to 5.25 million km2 still looks the most likely outcome.
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Juan C. García

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Re: 2018 sea ice area and extent data
« Reply #1113 on: July 22, 2018, 06:26:25 AM »
[ADS-NIPR-JAXA] NH ASI Extent has not been updated yet.  ???
Please help us posting the updated information, if it appears on the following link:

https://ads.nipr.ac.jp/vishop/#/extent
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.

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1114 on: July 22, 2018, 03:09:12 PM »
NSIDC Total Area as at 21 July (5 day trailing average =  5,433,425    km2
This has now stabilised atn 217 k above the 2010-2017 average


Total Area loss 95 K, Central Seas 79k, Periphery loss 7 k, Other Seas loss 9 k  
Analysis of individual seas.

Pacific Side
- The Okhotsk Sea area is 6 k - up 2 k over the last 2 days,
- The Bering Sea area is 2 k,
- Chukchi Sea loss 9 k,
- Beaufort Sea loss 6 k,
Atlantic Side
- Baffin Sea loss 3 k,
- Greenland Sea loss 3 k,
- Barents Sea loss 1 k -  area is 2 k, i.e. melting season over,
- The Kara Sea area loss 15 k,
- The Laptev Sea area loss 8 k.
CAB
- The Central Arctic Sea loss 13 k,
- The Canadian Archipelago loss  9 k,
- East Siberian Sea loss 19 k .
Other seas
- St Lawrence area at 1 k,
- Hudson Bay area loss 10 k.

Area loss average on the last 2 days. Extent losses were catching up with area losses, but only because area losses were low. Now area losses are back up, area minus extent values are flat. (graph attached)
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1115 on: July 22, 2018, 06:41:14 PM »
The data is now for 21st July. This means that the two maximum months of insolation are now past, and on average, daily area loss is already in decline. So I thought I would give all the area graphs an airing. Note they are all from NSIDC area 5 day trailing average data.

Here we go.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1116 on: July 22, 2018, 06:47:48 PM »
The data is now for 21st July. This means that the two maximum months of insolation are now past, and on average, daily area loss is already in decline. So I thought I would give all the area graphs an airing. Note they are all from NSIDC area 5 day trailing average data.

4 more graphs
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1117 on: July 22, 2018, 09:48:00 PM »
WHOOPS - INTERNET DIED (hot humid weather plays havoc with signal in areas with low reception anyway)
The data is now for 21st July. This means that the two maximum months of insolation are now past, and on average, daily area loss is already in decline. So I thought I would give all the area graphs an airing. Note they are all from NSIDC area 5 day trailing average data.

Yet 4 more graphs
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1118 on: July 22, 2018, 09:49:41 PM »
WHOOPS - INTERNET DIED (hot humid weather plays havoc with signal in areas with low reception anyway)
The data is now for 21st July. This means that the two maximum months of insolation are now past, and on average, daily area loss is already in decline. So I thought I would give all the area graphs an airing. Note they are all from NSIDC area 5 day trailing average data.

Last 3 graphs
"Para a Causa do Povo a Luta Continua!"
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Steven

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Re: 2018 sea ice area and extent data
« Reply #1119 on: July 22, 2018, 10:59:55 PM »
NSIDC daily sea ice area is currently 8th lowest for the date:


Juan C. García

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Re: 2018 sea ice area and extent data
« Reply #1120 on: July 23, 2018, 05:55:25 AM »
[ADS-NIPR-JAXA] ASI Extent.

July 21st, 2018: 7,578,275 km2, a century drop of -139,657 km2.
July 22nd, 2018: 7,460,007 km2, a century drop of -118,268 km2.

2018 is the ninth lowest on record.
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.

Phil42

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Re: 2018 sea ice area and extent data
« Reply #1121 on: July 23, 2018, 09:05:12 AM »
We had now 6 consecutive days with a drop of over 90'000 km2 and an average of 112'731 km2.

In just the last 4 days 2018 got 209'909 km2 (24.5%) closer to the record minimum (2011). The record minimum will only go down by ~190'000 km2 (average 63'300 km2 per day) in the next 3 days.

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1122 on: July 23, 2018, 11:54:21 AM »
JAXA ARCTIC EXTENT 7,460,007 km2(July 22, 2018)

Just to add to Juan's and Phil42's posts:-
Despite the impressive extent loss of 676k in 6 days,
- Extent is 401 k (5.4%) above the 2010's average extent on this date,
- Extent loss to date is still 660k km2 (9.3%) below the 2008-2017 average, with 71.2% of the average melting season done.

Resulting minimum from average remaining melt is down to 4.59 million km2, (excluding 2012 from the average 4.70 million km2). Range of results from last ten years remaining melt is 3.60 to 5.14 million km2.

6 days losses above average in a row and the last 3 days well over 100k, but that 2017 feeling fades but remains - extent losses even when above average never enough to catch up on the slow melt to date. There is, on average, less than 30% of further extent loss to go. Daily extent loss, on average, is already in significant decline. Nevertheless, A September minimum down one bin in the range of 4.50 to 5.00 million km2 now looks the most likely outcome.

The question only NSIDC data can answer is - which seas in the Arctic got hammered by this significant loss? Perhaps it will start to show up in NSIDC regional and area extent data (5 day averages) over the next few days.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1123 on: July 23, 2018, 12:28:31 PM »
And a new graph for your delectation.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1124 on: July 23, 2018, 02:44:46 PM »
NSIDC Total Area as at 22 July (5 day trailing average =  5,336,278 km2
This is at 210 k above the 2010-2017 average - down a bit 


Total Area loss 97 K, Central Seas 81k, Periphery loss87 k, Other Seas loss 9 k  
Analysis of individual seas.

Pacific Side
- The Okhotsk Sea area is 6 k,
- The Bering Sea area is 2 k,
- Chukchi Sea loss 10 k,
- Beaufort Sea loss 16 k,
Atlantic Side
- Baffin Sea loss 6 k,
- Greenland Sea loss 2 k,
- Barents Sea loss 0 k -  area is 2 k, i.e. melting season over,
- The Kara Sea area loss 12 k,
- The Laptev Sea area loss 8 k.
CAB
- The Central Arctic Sea loss 3 k,
- The Canadian Archipelago loss 7 k,
- East Siberian Sea loss 23 k .
Other seas
- St Lawrence area at 2 k,
- Hudson Bay area loss 9 k.

Area loss slightly above average on the last 2 days. Extent losses are catching up with area losses again.

Adding St Lawrence area graph - the sea that will not give up its last fragments of ice?
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Neven

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Re: 2018 sea ice area and extent data
« Reply #1125 on: July 23, 2018, 04:05:45 PM »
Extent losses are catching up with area losses again.

And so compactness goes up again:
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1126 on: July 23, 2018, 11:02:48 PM »
Some time ago I made NSIDC extent graphs in similar format to the area graphs.
Now average minimum is only about 50 days away,people are looking much more at extent.

So here are the extent graphs (NSIDC 5-day trailing average) as at 22 July 2018.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1127 on: July 23, 2018, 11:04:32 PM »
Some time ago I made NSIDC extent graphs in similar format to the area graphs.
Now average minimum is only about 50 days away,people are looking much more at extent.

So here are the extent graphs (NSIDC 5-day trailing average) as at 22 July 2018.

4 more graphs
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1128 on: July 23, 2018, 11:05:46 PM »
Some time ago I made NSIDC extent graphs in similar format to the area graphs.
Now average minimum is only about 50 days away,people are looking much more at extent.

So here are the extent graphs (NSIDC 5-day trailing average) as at 22 July 2018.

Yet 4 more graphs
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1129 on: July 23, 2018, 11:06:40 PM »
Some time ago I made NSIDC extent graphs in similar format to the area graphs.
Now average minimum is only about 50 days away,people are looking much more at extent.

So here are the extent graphs (NSIDC 5-day trailing average) as at 22 July 2018.

last 3  graphs
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Re: 2018 sea ice area and extent data
« Reply #1130 on: July 24, 2018, 12:08:15 AM »
That graph of the Kara Sea sports the cliffiest cliff I have ever seen.  ;D
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1131 on: July 24, 2018, 12:23:01 AM »
That graph of the Kara Sea sports the cliffiest cliff I have ever seen.  ;D

One looks at the graph for the whole Arctic - and it is actually rather boring. The contrast between the individual seas and the oddities (e.g. St Lawrence last remnants refusing to disappear) is where the fascination is for me.
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oren

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Re: 2018 sea ice area and extent data
« Reply #1132 on: July 24, 2018, 02:19:10 AM »
That graph of the Kara Sea sports the cliffiest cliff I have ever seen.  ;D
Indeed. But when it stops in a few days the total extent drops may slow as well.

Juan C. García

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Re: 2018 sea ice area and extent data
« Reply #1133 on: July 24, 2018, 05:56:42 AM »
[ADS-NIPR-JAXA] ASI Extent.

July 23rd, 2018: 7,335,434 km2, a century drop of -124,573 km2.

2018 is the ninth lowest on record.
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

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Re: 2018 sea ice area and extent data
« Reply #1134 on: July 24, 2018, 06:01:37 AM »
This is just a qualitative comment, but on the Bremen AMSR-2 map, I see a large area that could melt or be compressed, before the melting season is over.

Well, seems that the Arctic has its own will, so time will tell...
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.

Wherestheice

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Re: 2018 sea ice area and extent data
« Reply #1135 on: July 24, 2018, 06:11:46 AM »
The ice is having an impressive meltdown all of a sudden. I agree Juan that big patch looks like it won't last long and that will have a lot of affect on the extent data.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1136 on: July 24, 2018, 10:37:06 AM »
JAXA ARCTIC EXTENT 7,335,434 km2(July 23, 2018)

Just to add to Juan's post:-
One cannot deny that the extent loss of 801k in 7 days and 4 100k+ days in a row is impressive.,
- Extent is down to 240k k (3.3%) above the 2010's average extent on this date,
- Extent loss to date is still 610k km2 (8.5 %) below the 2008-2017 average, with 72% of the average melting season done.

Resulting minimum from average remaining melt is down to 4.54 million km2, (excluding 2012 from the average 4.65 million km2). Range of results from last ten years remaining melt is 3.57 to 5.09 million km2.

7 days losses above average in a row and the last 4 days well over 100k, but that 2017 feeling fades but lingers yet - extent losses are not yet enough to catch up on the slow melt to date. There is, on average, just 28% (51 days) of further extent loss to go. Daily extent loss, on average, is already in significant decline. Nevertheless, A September minimum down one bin in the range of 4.50 to 5.00 million km2 now looks increasingly the most likely outcome.
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Darvince

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Re: 2018 sea ice area and extent data
« Reply #1137 on: July 24, 2018, 11:53:41 AM »
How much of the recent cliff is driven by Kara vanishing suddenly? Because if it is, the cliff should end in a day or two and we go back to the slow loss that has otherwise characterized this season.

echoughton

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Re: 2018 sea ice area and extent data
« Reply #1138 on: July 24, 2018, 12:14:05 PM »
After Neven's splendid scientific explanation "Cliffiest Cliff" of recent Kara ice poofiness, one has to wonder where the floor is on this recent nose-dive.  :o

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Re: 2018 sea ice area and extent data
« Reply #1139 on: July 24, 2018, 12:30:35 PM »
How much of the recent cliff is driven by Kara vanishing suddenly? Because if it is, the cliff should end in a day or two and we go back to the slow loss that has otherwise characterized this season.

I think that will depend on what happens in the Beaufort Sea (and perhaps the ESS as well).
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Alexander555

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Re: 2018 sea ice area and extent data
« Reply #1140 on: July 24, 2018, 12:33:55 PM »
Maybe we wil see some more cliffiest cliffs. Over here it has been strange for already several months. In December and January there was almost no sun for 2 months. Than it was a few weeks very cold late in the winter. And a couple weeks later it was almost 30 degree C. And now it's hot and dry for already several weeks. Sounds like a cliffiest cliff environment.

Pmt111500

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Re: 2018 sea ice area and extent data
« Reply #1141 on: July 24, 2018, 01:05:53 PM »
Ok, I'll say it. Merely noting the CAB speedier drops of 2010s haven't yet started, so adding the average drop on there to the current value might be advisable. Kara is indeed showing the 'cliffiest cliff'.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1142 on: July 24, 2018, 02:14:31 PM »
NSIDC Total Area as at 23 July (5 day trailing average =  5,227,894  km2
This is at 183 k above the 2010-2017 average - down a bit more


Total Area loss 118 K, Central Seas 83k, Periphery loss 10 k, Other Seas loss 15 k  
Analysis of individual seas.

Pacific Side
- The Bering Sea area is 2 k,
- Chukchi Sea loss 8 k,
Atlantic Side
- Baffin Sea loss 6 k,
- Greenland Sea loss 3 k,
- Barents Sea loss 0 k -  area is 2 k, i.e. melting season over,
- The Kara Sea area loss 9 k, Area now just 82k.
- The Laptev Sea area loss 7 k.
CAB
- Beaufort Sea loss 18 k,
- The Central Arctic Sea loss 10 k,
- The Canadian Archipelago loss 6 k,
- East Siberian Sea loss 25 k .
Other seas
- St Lawrence area at 2 k,
- Hudson Bay area loss 15 k,
- The Okhotsk Sea area is 5 k.

Area loss slightly more above average on the last 2 days. Extent losses are catching up with area losses again. See graph

Note:
- Okhotsk Sea moved to other seas - it is so detached from the Arctic Ocean (sea, estuary, lagoon, whatever).
- Beaufort Sea moved to CAB - as it is one of the four seas that are always the most reluctant to melt. None as yet have lost 50% of their area maximum. Some will disagree, "but this post belongs to me"
« Last Edit: July 24, 2018, 03:50:48 PM by gerontocrat »
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colchonero

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Re: 2018 sea ice area and extent data
« Reply #1143 on: July 24, 2018, 02:33:54 PM »
@gerontocrat

Just one small correction. Total area loss =108k not 198k ;)

magnamentis

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Re: 2018 sea ice area and extent data
« Reply #1144 on: July 24, 2018, 03:25:58 PM »
That graph of the Kara Sea sports the cliffiest cliff I have ever seen.  ;D
Indeed. But when it stops in a few days the total extent drops may slow as well.

there are plenty more regions where it can repeat as far as i can see but yes, it "may" or may not ;)

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1145 on: July 24, 2018, 03:48:35 PM »
NSIDC daily Extent (One day observations) has been falling much quicker than area. So here is a graph to show it.

Also a crude table (maybe I will clean it up later) showing possible outcomes from remaining melt in previous years (as I do for JAXA)
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magnamentis

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Re: 2018 sea ice area and extent data
« Reply #1146 on: July 24, 2018, 03:51:22 PM »
something of that kind i expected in 2016 but apparently the ice is now thin in enough to make it happen, at least in parts, despite the lack of sunshine (cloudyness)

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #1147 on: July 24, 2018, 03:51:39 PM »
@gerontocrat

Just one small correction. Total area loss =108k not 198k ;)

Muchas Gracias, colchonero
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jdallen

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Re: 2018 sea ice area and extent data
« Reply #1148 on: July 24, 2018, 05:22:27 PM »
NSIDC daily Extent (One day observations) has been falling much quicker than area. So here is a graph to show it.

Also a crude table (maybe I will clean it up later) showing possible outcomes from remaining melt in previous years (as I do for JAXA)
And we are back to the 2010s average.
Statistically, most outcomes take us to the 4.25-4.75 million km2 range.
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Stephan

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Re: 2018 sea ice area and extent data
« Reply #1149 on: July 24, 2018, 07:38:29 PM »
There are maybe some few more "century melt days" in the pipeline. When I look at the "Uni Bremen" maps, it seems likely that Laptev and Chukchi (and, in parts, Beaufort) are some candidates for a more rapid melting. Also the remains in Kara, Hudson, Baffin and Grønland should decline markedly in the next 14 days. Whether this brings us below the 2010s average is still open -  time will tell...
For ESS and CAA I believe they will keep up with their "laggardness".
« Last Edit: July 24, 2018, 08:53:59 PM by Stephan »
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