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zufall

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Re: 2019 sea ice area and extent data
« Reply #2300 on: August 31, 2019, 08:27:05 AM »
Distance from Aug 30 to the 2011 minimum of 4,269,199 km²: 32,888 km²
Distance from Aug 30 to the 2015 minimum of 4,257,003 km²: 45,084 km²

Note: I managed to get a calculation error into my posting #2286 from yesterday even though it was so short  ;D

binntho

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Re: 2019 sea ice area and extent data
« Reply #2301 on: August 31, 2019, 08:42:26 AM »
https://ads.nipr.ac.jp/vishop/#/extent

Aug 30 extent: 4,302,087 km², down 26,568 km² from Aug 29.
Funny how we go to the same page and you find the exact number while I don't.
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zufall

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Re: 2019 sea ice area and extent data
« Reply #2302 on: August 31, 2019, 08:47:08 AM »
It's not displayed on the page, but there is a button "Download to sea ice extent data (CSV file)".

binntho

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Re: 2019 sea ice area and extent data
« Reply #2303 on: August 31, 2019, 09:11:42 AM »
It's not displayed on the page, but there is a button "Download to sea ice extent data (CSV file)".
Yes I tried that, but I couldn't get the figures to match. Probably just being stupid.
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2304 on: August 31, 2019, 11:26:32 AM »
JAXA ARCTIC SEA ICE EXTENT :- 4,302,087 km2(August 30, 2019)

JAXA daily extent loss in the last 2 weeks very much below average and on this day up to an almost respectable 27k.

- Extent is still 2nd lowest in the satellite record,
- Extent is 764 k greater than 2012, 0.3 k less than 2016.
- Extent loss on this day 27 k, 10 k less than the average loss on this day of 37 k.
- Extent loss from maximum 9,969 k, 400 k (4.2%) greater than the average of 9,569 k loss from maximum by this day,
- Extent loss from maximum to date is still second highest in at least the last 12 years, only second to 2012,, but on 31 August will be 3rd lowest,
- On average 96.8% of the melting season done, with 14 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt (0.35 million km) would give a minimum of 3.99 million km2, 2nd lowest in the satellite record, 0.81 million km2 above the 2012 low of 3.18 million km2 and 0.03 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 

On average, each day now consumes 7% of the time available for further extent loss. However, in the the last 10 years there were as few as 8 days or as many as 22 days of extent losses to come.

Given that Arctic temperature anomalies have been consistently above average and that SSTs have been and are very high, this two week stall in extent (and now area) loss is still a mystery to me, despite lots of info from posters who know a lot more than me.

But perhaps the final days of the season will ring the changes yet again.
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Pmt111500

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Re: 2019 sea ice area and extent data
« Reply #2305 on: August 31, 2019, 01:52:26 PM »
I'll say I'm disappointed of the late race perfomance by 2019. That looks like recovery started a couple of weeks ago. I bet next winter we'll see a proper Maximum and the mainstream researchers will have to abandon their current prognostics. (Again one of those -300€ bets, I'll bet negative euros and the bettee will have to pay me 300 if I'm wrong)
Cooling the outside by heat pump.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2306 on: August 31, 2019, 02:01:55 PM »
......and the bettee will have to pay me 300 if I'm wrong)
methinks the odds area stacked in your favour, along with the 5 aces in your pack of cards, and a little bit of lead for use in those poker dice?
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2307 on: August 31, 2019, 03:19:10 PM »
NSIDC Total Area as at 30 August 2019 (5 day trailing average)  2,970,238 km2

On this day the 5 day trailing average area increased by 4k, (by 21k the previous day). The one day area change was therefore a significant loss.
                        
Total Area         
 2,970,238    km2      
-305,039    km2   <   2010's average.
-197,465    km2   <   2018
-1,235,166    km2   <   2000's average.
         
Total Area Change    4    k   gain
Peripheral Seas   -4    k   loss
Central Seas__    8    k   gain
Other Seas___    0    k   gain
         
Peripheral Seas         
Bering _______    0    k   gain
Baffin  Bay____   -0    k   loss
Greenland____   -3    k   loss
Barents ______   -1    k   loss
         
CAB Seas         
Beaufort_____   -1    k   loss
CAA_________    1    k   gain
East Siberian__    2    k   gain
Central Arctic_    7    k   gain
         
Kara_________   -1    k   loss
Laptev_______   -1    k   loss
Chukchi______    0    k   gain
         
Other Seas         
Okhotsk______    1    k   gain
St Lawrence___    -    k   loss
Hudson Bay___   -0    k   loss
- Area GAIN 4 k, 35 k different from the 2010's average area LOSS of 31 k on this day,
- Total area 3rd Lowest, 279 k MORE than 2016, and 454 k MORE than 2012.

NSIDC one day extent manged to drop by a respectable 58k.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September.

This late in the season getting back any "shortfall" in area and extent losses is more difficult to get back (it is a matter of arithmetic). However, both the one day extent and area changes on this day were respectable losses. It is just possible the end-of-season might be waking up after its two week slumber.

But even so, end of season wobbles make comments out-of-date almost before they are typed.  Just sit back and watch, there will be plenty of autopsies over the next month or two.
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JUST ICE

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Re: 2019 sea ice area and extent data
« Reply #2308 on: August 31, 2019, 03:29:53 PM »
NSIDC extent for Aug 30 is 4.589 million Km2. Aug 22 was not the minimum. Anyone else not the least bit surprised?

Alphabet Hotel

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Re: 2019 sea ice area and extent data
« Reply #2309 on: August 31, 2019, 03:49:42 PM »
NSIDC daily extent

Killian

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Re: 2019 sea ice area and extent data
« Reply #2310 on: August 31, 2019, 04:02:46 PM »
...It is likely 2019 will fall to the third lowest northern hemisphere NSIDC sea ice area value for the date, in the next 4 days.
Oh look you are back at a convenient time yet you are still wrong, nothing has changed!

How can you say they are wrong on a forwardlooking statement? And, I essentially agree, though I'd put it more likely to be the 30th or 31st. Just look at the trend.

Worth noting, 2019 fell to 3rd the very same day, the 26th, making weatherdude correct and bbr wrong.

I, of course, was very wrong in being four days late with my guess. However, JAXA extent is tied for 3rd on the 30th (according to the graph and ignoring gerontocrat's 0.3k which must be well withing any error bars for the data), which I had predicted to occur on the 30th or 31st, so 1 out of 2 ain't bad.  ;) :P ::)

Careful with predictions... for or against.

And, it's not always raw data that tells one what they need to know. Trends, patterns matter.
« Last Edit: August 31, 2019, 04:07:55 PM by Killian »

DrTskoul

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Re: 2019 sea ice area and extent data
« Reply #2311 on: August 31, 2019, 06:46:52 PM »
I guess the fat lady has a few more notes...

Shared Humanity

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Re: 2019 sea ice area and extent data
« Reply #2312 on: August 31, 2019, 07:46:07 PM »
NSIDC extent for Aug 30 is 4.589 million Km2. Aug 22 was not the minimum. Anyone else not the least bit surprised?

count me as not surprised...

Jacobus

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Re: 2019 sea ice area and extent data
« Reply #2313 on: September 01, 2019, 06:04:52 AM »
Per JAXA

August 31st, 2019

4,259,262 km2    A drop of 42,825 km2 from yesterday.
« Last Edit: September 01, 2019, 06:14:11 AM by Jacobus »

Frivolousz21

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Re: 2019 sea ice area and extent data
« Reply #2314 on: September 01, 2019, 07:37:47 AM »
Considering momentum, heat in the water and everything else, the slowdown over the last week is nothing short of astonishing to me.

I really didn't expect to be wrong concluding extent this year would drop under 4 million KM2, but am happy that it appears it won't.

As I said elsewhere, seems there's a factor we are missing somehow.

I've been speculating for a while about that. Maybe, the ice is in such a bad condition that mostly volume is being lost at this point and the remaining ice continues to disperse, keeping up with the two-dimensional losses.  Of course, the only way we will know is to wait a couple weeks on  the PIOMAS numbers.

Nope.

Not going to get much ice loss in late August with a reverse dipole. This should have been expected weeks ago on the main thread.

The pattern going back almost 10 days has been great for the ice

The models are picking up a mini vortex dominant dipole for the next week.

So September loses will probably be above average.

But the slowdown would have happened any time during the melting season with weather that perfect for it
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binntho

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Re: 2019 sea ice area and extent data
« Reply #2315 on: September 01, 2019, 08:59:21 AM »
So I figured it out.  :P

On August 31st JAXA has 4,259,262 km2 with a drop of 42,825 km2 from the previous day.
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Stephan

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Re: 2019 sea ice area and extent data
« Reply #2316 on: September 01, 2019, 09:21:22 AM »
...which puts 2019 now in 3rd place behind 2012 and 2016. The following days 2016 showed significant extent losses, so one can assume that 2019 will stay behind 2016 in the next days (at least).
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zufall

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Re: 2019 sea ice area and extent data
« Reply #2317 on: September 01, 2019, 10:18:58 AM »
The 2011 minimum has been passed.

Distance from Aug 31 to the 2015 minimum of 4,257,003 km²: 2,259 km²
Distance from Aug 31 to the 2007 minimum of 4,065,739 km²: 193,523 km²

Steven

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Re: 2019 sea ice area and extent data
« Reply #2318 on: September 01, 2019, 10:46:05 AM »
JAXA extent graph:


binntho

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Re: 2019 sea ice area and extent data
« Reply #2319 on: September 01, 2019, 11:00:50 AM »
Methinks 2019 can still surprise us (yet again!)
because a thing is eloquently expressed it should not be taken to be as necessarily true
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2320 on: September 01, 2019, 11:32:34 AM »
JAXA ARCTIC SEA ICE EXTENT :- 4,259,262 km2(August 31, 2019)

After the last 2 weeks of very much below average JAXA daily extent losses, on this day extent loss increased to an above average 43k (after the previous day's almost respectable 27k).

- Extent is now 3rd lowest in the satellite record,
- Extent is 764 k greater than 2012, 17 k greater than 2016.
- Extent loss on this day 43 k, 7 k MORE than the average loss on this day of 36 k.
- Extent loss from maximum 10,012 k, 407 k (4.2%) greater than the average of 9,605 k loss from maximum by this day,
- Extent loss from maximum to date is still second highest in at least the last 12 years, only second to 2012,
- On average 97.2% of the melting season done, with 13 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt (0.28 million km) would give a minimum of 3.98 million km2, 2nd lowest in the satellite record, 0.80 million km2 above the 2012 low of 3.18 million km2 and 0.04 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 

Each day now consumes nearly 8% of the average time available for further extent loss. However, in the the last 10 years there were as few as 7 days or as many as 21 days of extent losses to come.

But perhaps the final days of the season will ring the changes yet again. With very high SSTs and bottom melt still underway, this could provide the conditions for a later date of minimum as well as a slow refreeze (if surface weather conditions are at least not unfavourable)
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2321 on: September 01, 2019, 11:59:35 AM »
JAXA ARCTIC SEA ICE EXTENT :- 4,259,262 km2(August 31, 2019) OTHER STUFF

Remaining Extent Losses to Minimum
I attach the plume graph of projected minima from previous years' remaining extent loss. Of interest (at least to me) is that 2018 continued losing extent beyond the average date to a record 21 September despite an overall poor melting season. The clear leader in September extent loss was 2010 - 82% above the average.

In contrast  2016 September extent losses were 18% below average and the date of minimum was nearly a week earlier than average - on 7 September.

Extent 31 August c.f. previous years' minima
If extent losses stopped now, 2019 would be 5th lowest in the satellite record, a mere 2k (above 2015) denying a 4th place.

This is already 134k below the 2010's average minimum, which in my view is probably more significant than that the 2012 minimum is 1,082k km2 below the 2019 current extent.

365 Day Trailing Average

The graph shows continued steep declines towards a new record low in early 2020. Some decline is inevitable in the immediate future, simply because 2019 extent on this day is 483k less than 2018, and even if refreeze is early and extent rises quickly it will take some time for 2019 to catch up to 2018.

Something to watch as/when refreeze commences.
« Last Edit: September 01, 2019, 12:10:06 PM by gerontocrat »
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2322 on: September 01, 2019, 03:30:56 PM »
NSIDC Total Area as at 31 August 2019 (5 day trailing average)  2,977,774 km2

On this day the 5 day trailing average area increased by 7.5k, (by 4k the previous day). This in contrast to the one-day NSIDC extent loss of 73k (58k the day before).
                        
Total Area         
 2,977,774    km2      
-267,702    km2   <   2010's average.
-472,777    km2   <   2018
-1,203,999    km2   <   2000's average.
         
Total Area Change    8    k   gain
Peripheral Seas   -6    k   loss
Central Seas__    14    k   gain
Other Seas___   -1    k   loss
         
Peripheral Seas         
Bering _______    0    k   gain
Baffin  Bay____   -1    k   loss
Greenland____   -5    k   loss
Barents ______   -0    k   loss
         
CAB Seas         
Beaufort_____    0    k   gain
CAA_________    1    k   gain
East Siberian__    1    k   gain
Central Arctic_    13    k   gain
         
Kara_________    0    k   gain
Laptev_______   -2    k   loss
Chukchi______    1    k   gain
         
Other Seas         
Okhotsk______   -0    k   loss
St Lawrence___    -    k   loss
Hudson Bay___   -1    k   loss
- Area GAIN 8 k, 39 k different from the 2010's average area LOSS of 31 k on this day,
- Total area 3rd Lowest, 300 k MORE than 2016, and 486 k MORE than 2012.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September.

This late in the season getting back any "shortfall" in area and extent losses is more difficult to get back (it is a matter of arithmetic). However, the one day extent changes in the last 2 days were respectable losses. It is just possible the end-of-season might be waking up after its two week slumber. Or area will continue to diverge from extent.

But even so, end of season wobbles make comments out-of-date almost before they are typed.  Just sit back and watch, there will be plenty of autopsies over the next month or two.
« Last Edit: September 01, 2019, 03:41:01 PM by gerontocrat »
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2323 on: September 01, 2019, 03:46:36 PM »
NSIDC Total Area as at 31 August 2019 (5 day trailing average)  2,977,774 km2 - OTHER STUFF


The Greenland Sea is the only sea that has consistently lost sea ice area in the last week or so.

The NSIDC 5-day Trailing Average Extent Graph also shows the stalling of extent loss - which has changed in the last two days.

Extent losses vs Area gains have increased concentration / compaction. i.e. dispersion reducing again.
« Last Edit: September 01, 2019, 09:36:15 PM by gerontocrat »
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Re: 2019 sea ice area and extent data
« Reply #2324 on: September 01, 2019, 08:02:16 PM »
NSIDC daily area is currently 2.97 million km2, which is third lowest for the date:



The year-to-date minimum for this year so far is 2.88 million km2 on 24 August 2019.

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Re: 2019 sea ice area and extent data
« Reply #2325 on: September 01, 2019, 08:16:49 PM »
NSIDC daily area is currently 2.97 million km2, which is third lowest for the date:

The year-to-date minimum for this year so far is 2.88 million km2 on 24 August 2019.
Area flattening before than extent is normal.
If area stays at this level, —-and cannot see a reason why it should go much lower at this time, with no surface melt, and overall melt going down quickly during September—-, extent has still some room to fall further (because of current dispersion) but will probably stay fourth, maybe third in monthly average.
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Re: 2019 sea ice area and extent data
« Reply #2326 on: September 01, 2019, 09:23:24 PM »
The surface wind forecasts are pretty damn compelling for the potential for above normal extent driops the next 7 days. 

It will depend on how thin the remaining low concentration ice actually is.

Because winds are very very favorable for both low concentration maximas on Bremen to shrink considerably.

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Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #2327 on: September 02, 2019, 05:45:26 AM »
September 1st, 2019:
     4,248,474 km2, a drop of -10,788 km2.
     2019 is 3rd lowest on record.
     (2012 & 2016 highlighted).
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: 2019 sea ice area and extent data
« Reply #2328 on: September 02, 2019, 05:52:53 AM »
With the ADS-JAXA ASI extent of September 1st, the daily minimum of 2019 is now fourth 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.

Alphabet Hotel

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Re: 2019 sea ice area and extent data
« Reply #2329 on: September 02, 2019, 06:15:41 AM »
NSIDC daily extent

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Re: 2019 sea ice area and extent data
« Reply #2330 on: September 02, 2019, 09:41:30 AM »
Is there a structural reason for the massive discrepancy of -10k from Juan G and - 73k NSIDC daily from Alphabet Hotel.  i.e one is yesterday vs today? 


In which case can we expect one to "catch up" tomorrow?

grixm

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Re: 2019 sea ice area and extent data
« Reply #2331 on: September 02, 2019, 09:51:03 AM »
Is there a structural reason for the massive discrepancy of -10k from Juan G and - 73k NSIDC daily from Alphabet Hotel.  i.e one is yesterday vs today? 


In which case can we expect one to "catch up" tomorrow?

Juan's is based on JAXA which is much higher resolution than NSIDC. This will cause them to be somewhat different, even long-term so it's not a necessity that one catches up to the other.

Killian

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Re: 2019 sea ice area and extent data
« Reply #2332 on: September 02, 2019, 10:00:10 AM »
Some August data breakdowns and comparisons. PM me if you want the spreadsheets.


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Re: 2019 sea ice area and extent data
« Reply #2333 on: September 02, 2019, 11:28:30 AM »
JAXA ARCTIC SEA ICE EXTENT :- 4,248,474 km2(September 1, 2019)

On this day extent loss decreased to a feeble below average 11k (after the previous day's respectable 43k ).

- Extent is now 3rd lowest in the satellite record,
- Extent is 773 k greater than 2012, 80 k greater than 2016.
- Extent loss on this day 11 k, 17 k LESS than the average loss on this day of 28 k.
- Extent loss from maximum 10,023 k, 390 k (4.1%) greater than the average of 9,633 k loss from maximum by this day,
- Extent loss from maximum to date is still second highest in at least the last 12 years, only second to 2012,
- If extent loss stopped on this day, 2019 would be the 4th lowest minimum in the satellite record (just 2012, 2016 and 2007 less),
- On average 97.5% of the melting season done, with 12 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt (0.25 million km) would give a minimum of 4.00 million km2, 2nd lowest in the satellite record, 0.82 million km2 above the 2012 low of 3.18 million km2 and 0.02 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 

Each day now consumes 8% of the average time available for further extent loss. However, in the the last 10 years there were as few as 7 days or as many as 21 days of extent losses to come.

But perhaps the final days of the season will ring the changes yet again. With very high SSTs and bottom melt still underway, this could provide the conditions for a later date of minimum as well as a slow refreeze (if surface weather conditions are at least not unfavourable)
____________________________________________________________
Friv mentioned the possibility of high extent losses in September - and look what happens, extent loss on this day barely more than 1/3rd of average. There are times I get  anthropomorphic about sea ice, and ascribe malevolence to its nature.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2334 on: September 02, 2019, 03:26:09 PM »
NSIDC Total Area as at 1 September 2019 (5 day trailing average)  2,969,583 km2

On this day the 5 day trailing average area decreased by 8k, (8k increase the previous day). This in contrast to the one-day NSIDC extent loss of 97k (73k & 58k the days before).
                        
Total Area         
 2,969,583    km2      
-249,147    km2   <   2010's average.
-446,613    km2   <   2018
-1,186,307    km2   <   2000's average.
         
Total Area Change   -8    k   loss
Peripheral Seas   -8    k   loss
Central Seas__    3    k   gain
Other Seas___   -4    k   loss
         
Peripheral Seas         
Bering _______   -0    k   loss
Baffin  Bay____   -2    k   loss
Greenland____   -5    k   loss
Barents ______   -1    k   loss
         
CAB Seas         
Beaufort_____    1    k   gain
CAA_________    1    k   gain
East Siberian__   -2    k   loss
Central Arctic_    6    k   gain
         
Kara_________   -0    k   loss
Laptev_______   -3    k   loss
Chukchi______    0    k   gain
         
Other Seas         
Okhotsk______   -2    k   loss
St Lawrence___    -    k   loss
Hudson Bay___   -2    k   loss
- Area LOSS 8 k, 22 k different from the 2010's average area LOSS of 30 k on this day,
- Total area 3rd Lowest, 312 k MORE than 2016, and 506 k MORE than 2012.
________________________________________________________________________
Outlook
We are now well into the last few days of reducing and very variable daily area loss that that will slide to zero by mid-September.

This late in the season getting back any "shortfall" in area and extent losses is more difficult to get back (it is a matter of arithmetic). However, the one day extent changes in the last 3 days were, given the time of year, very large losses. It is just possible the end-of-season might be waking up after its two week slumber. Or area will continue to diverge from extent.

On the 2019 melting season thread there have been many great posts showing satellite images of various parts of the Arctic sea ice reduced to rubble, whisps and lots of open water mixed in. There have been also compelling illustrations how it is is likely that even the sensors with the finest resolution are oftimes confused by the rotten state of the remaining ice. This may well have something to do with the recent divergences between extent and area changes measured.

But even so, end of season wobbles make comments out-of-date almost before they are typed.  Just sit back and watch, there will be plenty of autopsies over the next month or two.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Richard Rathbone

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Re: 2019 sea ice area and extent data
« Reply #2335 on: September 02, 2019, 03:31:42 PM »
Is there a structural reason for the massive discrepancy of -10k from Juan G and - 73k NSIDC daily from Alphabet Hotel.  i.e one is yesterday vs today? 


In which case can we expect one to "catch up" tomorrow?

Juan's is based on JAXA which is much higher resolution than NSIDC. This will cause them to be somewhat different, even long-term so it's not a necessity that one catches up to the other.


It is also yesterday vs. today, JAXA is a two day difference and thats the NSIDC one day difference.

Also not a massive discrepancy. Taking the difference between noisy measurements magnifies the effect of the noise.
« Last Edit: September 02, 2019, 03:43:28 PM by Richard Rathbone »

Alphabet Hotel

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Re: 2019 sea ice area and extent data
« Reply #2336 on: September 02, 2019, 04:08:51 PM »
NSIDC daily extent

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2337 on: September 02, 2019, 06:19:10 PM »
NSIDC Total Area as at 1 September 2019 (5 day trailing average)  2,969,583 km2


It's raining - and stuffed up my work outside. So here is some more stuff -Area analysis in JAXA format

- Area is 506k > 2012, 312 > 2016,
- Area is 3rd lowest in the satellite record,
- Area is 32k than the minimum on 25 August, but..
- there is an average Area loss of 170k to go, so too early to call a minimum,

That average area loss would produce a minimum Area of 2.80 million km2, 3rd lowest. The plume of resulting minima from the previous 10 years' remaining area losses is attached.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #2338 on: September 03, 2019, 02:21:45 AM »
I will be late at home tonight. If someone makes the ADS NIPR post, I will appreciate it.  ;)
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.

Jacobus

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Re: 2019 sea ice area and extent data
« Reply #2339 on: September 03, 2019, 05:28:00 AM »
Per JAXA

September 2nd, 2019:

4,214,615 km2   A drop of 33,859 km2 from yesterday.

binntho

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Re: 2019 sea ice area and extent data
« Reply #2340 on: September 03, 2019, 06:07:09 AM »
Per JAXA

September 2nd, 2019:

4,214,615 km2   A drop of 33,859 km2 from yesterday.
So what are the changes that those 214.615 km2 won't disappear this summer? Average remaining melt, according to Gerontocrat, would do it. Methinks 2nd place is still a very strong contender.
« Last Edit: September 03, 2019, 06:37:02 AM by binntho »
because a thing is eloquently expressed it should not be taken to be as necessarily true
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Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #2341 on: September 03, 2019, 07:17:54 AM »
Thanks Jacobus.  :)
September 2nd, 2019:
     4,214,615 km2, a drop of -33,859 km2.
     2019 is 3rd lowest on record.
     (2012 & 2016 highlighted).
« Last Edit: September 03, 2019, 07:24:12 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.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2342 on: September 03, 2019, 12:57:58 PM »
JAXA ARCTIC SEA ICE EXTENT :- 4,214,615 km2(September 2, 2019)

On this day extent loss increased to an above average 34k.
- Extent is 3rd lowest in the satellite record,
- Extent is 769 k greater than 2012, 124 k greater than 2016.
- Extent loss on this day 34 k, 11 k MORE than the average loss on this day of 23 k.
- Extent loss from maximum 10,057 k, 401 k (4.2%) greater than the average of 9,656 k loss from maximum by this day,
- Extent loss from maximum to date is still second highest in at least the last 12 years, only second to 2012,
- If extent loss stopped on this day, 2019 would be the 4th lowest minimum in the satellite record (just 2012, 2016 and 2007 less),
- On average 97.7% of the melting season done, with 11 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt (0.25 million km) would give a minimum of 3.99 million km2, 2nd lowest in the satellite record, 0.81 million km2 above the 2012 low of 3.18 million km2 and 0.03 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 

Each day now consumes 9% of the average time available for further extent loss. However, in the the last 10 years there were as few as 5 days or as many as 19 days of extent losses to come.

Perhaps the final days of the season will ring the changes yet again. With very high SSTs and bottom melt still underway, this could provide the conditions for a later date of minimum as well as a slow refreeze (if surface weather conditions are at least not unfavourable)
____________________________________________________________
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #2343 on: September 03, 2019, 03:27:09 PM »
NSIDC Total Area as at 2 September 2019 (5 day trailing average)  2,951,828 km2

On this day the 5 day trailing average area decreased by 18k, (8k decrease the previous day). One-day NSIDC extent loss 21k (97k, 73k & 58k the days before).
                        
Total Area         
 2,951,828    km2      
-244,233    km2   <   2010's average.
-436,473    km2   <   2018
-1,177,706    km2   <   2000's average.
         
Total Area Change   -18    k   loss
Peripheral Seas   -2    k   loss
Central Seas__   -12    k   loss
Other Seas___   -3    k   loss
         
Peripheral Seas         
Bering _______   -0    k   loss
Baffin  Bay____   -1    k   loss
Greenland____   -1    k   loss
Barents ______   -0    k   loss
         
CAB Seas         
Beaufort_____    5    k   gain
CAA_________   -1    k   loss
East Siberian__   -3    k   loss
Central Arctic_   -3    k   loss
         
Kara_________   -2    k   loss
Laptev_______   -7    k   loss
Chukchi______   -1    k   loss
         
Other Seas         
Okhotsk______   -1    k   loss
St Lawrence___    -    k   loss
Hudson Bay___   -2    k   loss
- Area LOSS 18 k, 9 k less than the 2010's average area LOSS of 7 k on this day,
- Total area 3rd Lowest, 319 k MORE than 2016, and 510 k MORE than 2012, and still 14k more than the current minimum of 25th August.
________________________________________________________________________
Outlook
We are now well into the last few days of reducing and very variable daily area loss that that will slide to zero by around mid-September.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

kassy

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Re: 2019 sea ice area and extent data
« Reply #2344 on: September 03, 2019, 05:27:04 PM »
Area LOSS 18 k, 9 k less than the 2010's average area LOSS of 7 k

I miss a 2 there.

Another interesting season so thanks for the updates all.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Alphabet Hotel

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Re: 2019 sea ice area and extent data
« Reply #2345 on: September 03, 2019, 05:58:39 PM »
NSIDC daily extent

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #2346 on: September 04, 2019, 05:41:28 AM »
September 3rd, 2019:
     4,174,722 km2, a drop of -39,893 km2.
     2019 is 3rd lowest on record.
     (2012 & 2016 highlighted).
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.

Espen

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Re: 2019 sea ice area and extent data
« Reply #2347 on: September 04, 2019, 07:42:20 AM »
Interesting comparison:
Have a ice day!

Espen

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Re: 2019 sea ice area and extent data
« Reply #2348 on: September 04, 2019, 07:47:56 AM »
A pixel color comparison could be very interesting?
Have a ice day!

zufall

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Re: 2019 sea ice area and extent data
« Reply #2349 on: September 04, 2019, 07:57:42 AM »
Distance from Sep 3 to the 2007 minimum of 4,065,739 km²: 108,983 km²
Distance from Sep 3 to the 2016 minimum of 4,022,615 km²: 152,107 km²